US20080067076A1 - Method of reducing oxygen content in ECP solution - Google Patents
Method of reducing oxygen content in ECP solution Download PDFInfo
- Publication number
- US20080067076A1 US20080067076A1 US11/523,135 US52313506A US2008067076A1 US 20080067076 A1 US20080067076 A1 US 20080067076A1 US 52313506 A US52313506 A US 52313506A US 2008067076 A1 US2008067076 A1 US 2008067076A1
- Authority
- US
- United States
- Prior art keywords
- solution
- substrate
- aerobic bacteria
- electroplating bath
- electroplating
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D3/00—Electroplating: Baths therefor
- C25D3/02—Electroplating: Baths therefor from solutions
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F3/00—Biological treatment of water, waste water, or sewage
- C02F3/34—Biological treatment of water, waste water, or sewage characterised by the microorganisms used
Definitions
- the present invention relates to electrochemical plating (ECP) processes used to deposit metal layers on semiconductor wafer substrates in the fabrication of semiconductor integrated circuits. More particularly, the present invention relates to a method of reducing the oxygen content of an electroplating bath solution by adding aerobic bacteria to the solution in order to enhance the quality of an electroplated metal film.
- ECP electrochemical plating
- the copper layer When a copper layer is deposited on a substrate, such as by electrochemical plating, the copper layer must be deposited on a metal seed layer such as copper, which is deposited on the substrate prior to the copper ECP process.
- a metal seed layer such as copper
- Conventional electrochemical plating techniques typically use copper sulfate (CuSO 4 ) for the main electrolyte in the electroplating bath solution.
- the solution may further include additives such as chloride ion and levelers, as well as accelerators and suppressors, which increase and decrease, respectively, the rate of the electroplating process.
- the rate of deposition of copper on the substrate, and the quality and resulting electrical and mechanical properties of the metallization are critically dependent on the concentration of these organic additives in the electroplating bath solution.
- the electroplating bath solution is continually circulated from and back to the bath container, respectively.
- This circulation of the solution often induces the formation of oxygen micro-bubbles in the solution.
- the micro-bubbles tend to become trapped at various locations on the seed layer deposited on the wafer and block deposition of the metal film onto the seed layer at those locations.
- the metal film is unevenly plated on the seed layer.
- CMP chemical mechanical planarization
- a novel method is needed to reduce the oxygen content in an electrochemical plating bath solution in order to prevent or at least reduce the formation of bubble-induced defects in a metal film or line electroplated onto a wafer.
- the present invention is generally directed to a novel method, which is suitable to substantially reduce the presence of oxygen micro-bubbles in an electroplating bath solution.
- the method includes the addition of aerobic bacteria to the electroplating bath solution to consume oxygen in the solution. Reduction of the oxygen content in the electroplating bath solution prevents oxygen micro-bubbles from forming in the solution and becoming trapped between the solution and the surface of a metal seed layer on a substrate to block the electroplating of a metal film onto the seed layer. Consequently, the presence of surface pits and other structural defects in the surface of the electroplated metal film is substantially reduced.
- the present invention is further directed to a metal film having a substantially reduced number of surface pits, voids and other defects.
- the metal film is plated onto a substrate by providing an electrochemical plating solution, adding aerobic bacteria to the solution, immersing the substrate in the solution, and carrying out an electroplating process in the solution.
- FIG. 1 is a schematic of an electrochemical plating system in implementation of the present invention
- FIG. 1A is a cross-sectional view of a wafer substrate with a metal film electroplated thereon according to the method of the present invention
- FIG. 2 is a flow diagram illustrating a typical flow of process steps carried out according to the method of the present invention.
- FIG. 3 is a graph in which the concentration of dissolved oxygen (DO) in an electroplating bath solution to which aerobic bacteria have been added is compared to the concentration of dissolved oxygen in an electroplating bath solution devoid of aerobic bacteria.
- DO dissolved oxygen
- the present invention has particularly beneficial utility in the electrochemical plating of a high-quality copper film on a copper seed layer deposited on a semiconductor wafer substrate in the fabrication of semiconductor integrated circuits.
- the invention is more generally applicable to the electrochemical plating of metals including but not limited to copper on substrates in a variety of industrial applications including but not limited to semiconductor fabrication.
- the present invention is generally directed to a novel method for substantially reducing the presence of oxygen micro-bubbles in an electroplating bath solution used to electroplate a metal film on a seed layer provided on a substrate.
- the method facilitates the electroplating of a metal film which is substantially devoid of voids and surface pits onto the seed layer.
- an aerobic bacteria is added to the electroplating bath solution.
- the aerobic bacteria consumes all or most of the oxygen in the solution to prevent or reduce the formation of oxygen micro-bubbles in the solution typically as the solution is circulated through the bath container. Consequently, micro-bubble blockage of metal electroplated onto the seed layer is prevented or at least substantially reduced.
- the present invention is further directed to a metal film having a substantially reduced number of surface pits, voids and other defects.
- the metal film is plated onto a substrate by providing an electrochemical plating solution, adding aerobic bacteria to the solution, immersing the substrate in the solution, and carrying out an electroplating process in the solution.
- the method of the present invention may be used with any formulation for the electrochemical plating bath solution, such as copper, aluminum, nickel, chromium, zinc, tin, gold, silver, lead and cadmium electrochemical plating baths.
- the present invention is also suitable for use with electrochemical plating baths containing mixtures of metals to be plated onto a substrate.
- the electroplating bath be a copper alloy electroplating bath, and more preferably, a copper electroplating bath.
- Typical copper electroplating bath formulations are well known to those skilled in the art and include, but are not limited to, an electrolyte and one or more sources of copper ions.
- Suitable electrolytes include, but are not limited to, sulfuric acid, acetic acid, fluoroboric acid, methane sulfonic acid, ethane sulfonic acid, trifluormethane sulfonic acid, phenyl sulfonic acid, methyl sulfonic acid, p-toluenesulfonic acid, hydrochloric acid, phosphoric acid and the like.
- the acids are typically present in the bath in a concentration in the range of from about 1 to about 300 g/L.
- the acids may further include a source of halide ions such as chloride ions.
- Suitable sources of copper ions include, but are not limited to, copper sulfate, copper chloride, copper acetate, copper nitrate, copper fluoroborate, copper methane sulfonate, copper phenyl sulfonate and copper p-toluene sulfonate.
- Such copper ion sources are typically present in a concentration in the range of from about 10 to about 300 g/L of electroplating solution.
- Aerobic bacteria which are suitable for implementation of the present invention include nitrifying bacterial agents, Bdellovibrio bacteriovorus, Acinetobacter calcoaceticus, Pseudamonas fluorescens, Arthrobacter globiformis , and Acetobacter pasteurianus .
- the aerobic bacteria is a nitrifying bacterial agent.
- the aerobic bacteria are present in the electroplating bath solution in a concentration of from typically about 1 ml/l to about 5 ml/l.
- electrochemical plating process conditions suitable for implementation of the present invention include a plating rpm of from typically about 0 rpm to about 500 rpm; a plating current of from typically about 0.2 mA/cm 2 to about 20 mA/cm 2 ; and a bath temperature of from typically about 10 degrees C. to about 35 degrees C.
- a leveling agent may be added to the electroplating bath solution at a concentration of from typically about 5 mmol/L to about 5 mol/L.
- an electrochemical plating (ECP) system 10 which is suitable for implementation of the present invention is shown.
- the system 10 may be conventional and includes a standard electroplating cell having an adjustable current source 12 , a bath container 14 , a typically copper anode 16 and a cathode 18 , which cathode 18 is the semiconductor wafer substrate that is to be electroplated with copper.
- the anode 16 and cathode/substrate 18 are connected to the current source 12 by means of suitable wiring 38 .
- the bath container 14 holds an electrolyte electroplating bath solution 20 .
- the system 10 may further include a mechanism for rotating the substrate 18 in the bath 20 during the electroplating process, as is known by those skilled in the art.
- the ECP system 10 may further include a pair of bypass filter conduits 24 , a bypass pump/filter 30 , and an electrolyte holding tank 34 .
- the bypass filter conduits 24 typically extend through the anode 16 and open to the upper, oxidizing surface 22 of the anode 16 at opposite ends of the anode 16 .
- the bypass filter conduits 24 connect to the bypass pump/filter 30 located outside the bath container 14 , and the bypass pump/filter 30 is further connected to the electrolyte holding tank 34 through a tank inlet line 32 .
- the electrolyte holding tank 34 is, in turn, connected to the bath container 14 through a tank outlet line 36 . It is understood that the ECP system 10 heretofore described represents just one example of a possible system which is suitable for implementation of the present invention, and other systems of alternative design may be used instead.
- a metal seed layer 19 such as copper is deposited on a wafer substrate 18 , as indicated in step S 1 of FIG. 2 .
- the metal seed layer 19 may be deposited on the substrate 18 using conventional chemical vapor deposition (CVD) or physical vapor deposition (PVD) techniques, for example, according to the knowledge of those skilled in the art.
- the seed layer 19 has a thickness of typically about 50 ⁇ 1500 angstroms.
- the electrochemical plating (ECP) electrolyte bath solution 20 is prepared in the bath container 14 .
- the electroplating bath solution 20 may include an accelerator having a concentration of from typically about 5 mmol/L to about 5 mol/L, and may include a leveling agent or additive in a concentration of from typically about 5 mmol/L to about 5 mol/L, as heretofore noted.
- the aerobic bacteria 25 of the present invention is added to the electroplating bath solution 20 , which is then circulated from the bath container 14 , through the electrolyte holding tank 34 and back to the bath container 14 , by operation of the pump 30 , to achieve an aerobic bacteria concentration of from typically about 1 ml/l to typically about 5 ml/l in the electroplating bath solution 20 .
- the anode 16 and substrate 18 are then immersed in the bath solution 20 and connected to the adjustable current source 12 , typically through wiring 38 . Accordingly, the seed layer 19 on the substrate 18 contacts the bath solution 20 .
- the entire surface of the seed layer 19 , as well as gap features on the substrate 18 is thoroughly wetted by the bath solution 20 .
- the bath 20 is continually circulated from the bath container 14 through the bypass filter conduits 24 , electrolyte holding tank 34 and back into the bath container 14 , respectively, by operation of the pump 30 .
- This maintains the copper sulfate or other electrolyte in a dissolved state in the electroplating bath solution 20 , and prevents or minimizes precipitation of the electrolyte onto the sides, bottom and other surfaces of the bath container 14 , throughout the electroplating process.
- dissolved oxygen normally forms oxygen micro-bubbles (not shown) in the bath solution 20 .
- the aerobic bacteria 25 having been previously added to the bath solution 20 at step S 3 of FIG. 2 , consume all or most of the oxygen present in the bath solution 20 . This eliminates or substantially reduces the quantity of oxygen micro-bubbles which form in the solution 20 . Consequently, the presence of micro-bubbles between the bath solution 20 and the seed layer 19 on the substrate 18 is eliminated or substantially reduced during the subsequent electroplating process, which will be hereinafter described.
- a metal film 21 is electroplated onto the seed layer 19 , as shown in FIG. 1A and indicated in step S 5 of FIG. 2 , typically as follows.
- the electroplating bath solution 20 is maintained at a temperature of from typically about 10 degrees C. to about 35 degrees C.
- the plating rpm for the substrate 18 is typically about 0-500 rpm.
- the current source 12 applies a selected voltage potential, typically at room temperature, between the anode 16 and the cathode/substrate 18 .
- This voltage potential creates a magnetic field around the anode 16 and the cathode/substrate 18 , which magnetic field affects the distribution of the copper ions in the bath solution 20 .
- a voltage potential of about 2 volts may be applied for about 2 minutes, and a plating current of from typically about 0.2 mA/cm 2 to about 20 mA/cm 2 flows between the anode 16 and the cathode/substrate 18 .
- the electroplated metal film 21 deposited onto the seed layer 19 is substantially continuous and devoid of structural deformities such as voids, pits and broken metal lines. Accordingly, the electroplated metal film 21 on the substrate 18 contributes to the fabrication of high-quality IC devices that are characterized by high structural and operational integrity.
- FIG. 3 illustrates a graph in which the concentration of dissolved oxygen (DO) in an electroplating bath solution to which aerobic bacteria have been added is compared to the concentration of dissolved oxygen in an electroplating bath solution devoid of aerobic bacteria. From a consideration of the graph, it can be seen that the addition of aerobic bacteria to an electroplating bath solution is capable of reducing the concentration of dissolved oxygen (DO) in the solution from about 5 mg/l to about 2 mg/l.
Abstract
A novel method, which is suitable to substantially reduce the presence of oxygen micro-bubbles in an electroplating bath solution, is disclosed. The method includes the addition of aerobic bacteria to the electroplating bath solution to consume oxygen in the solution. Reduction of the oxygen content in the electroplating bath solution prevents oxygen micro-bubbles from forming in the solution and becoming trapped between the solution and the surface of a metal seed layer on a substrate to block the electroplating of a metal film onto the seed layer. Consequently, the presence of surface pits and other structural defects in the surface of the electroplated metal film is substantially reduced.
Description
- The present invention relates to electrochemical plating (ECP) processes used to deposit metal layers on semiconductor wafer substrates in the fabrication of semiconductor integrated circuits. More particularly, the present invention relates to a method of reducing the oxygen content of an electroplating bath solution by adding aerobic bacteria to the solution in order to enhance the quality of an electroplated metal film.
- When a copper layer is deposited on a substrate, such as by electrochemical plating, the copper layer must be deposited on a metal seed layer such as copper, which is deposited on the substrate prior to the copper ECP process. Conventional electrochemical plating techniques typically use copper sulfate (CuSO4) for the main electrolyte in the electroplating bath solution. The solution may further include additives such as chloride ion and levelers, as well as accelerators and suppressors, which increase and decrease, respectively, the rate of the electroplating process. The rate of deposition of copper on the substrate, and the quality and resulting electrical and mechanical properties of the metallization, are critically dependent on the concentration of these organic additives in the electroplating bath solution.
- Throughout the electroplating process, the electroplating bath solution is continually circulated from and back to the bath container, respectively. This circulation of the solution often induces the formation of oxygen micro-bubbles in the solution. The micro-bubbles tend to become trapped at various locations on the seed layer deposited on the wafer and block deposition of the metal film onto the seed layer at those locations. As a result, the metal film is unevenly plated on the seed layer. During subsequent chemical mechanical planarization (CMP) of the electroplated metal film, this phenomenon is manifested by the presence of defects in the form of pits, voids, broken metal lines and other defects in device features on the wafer. The presence of pits, voids and broken metal lines in device features leads to unreliable, unpredictable and unuseable electronic devices in the electronic circuit containing the features. Accordingly, a novel method is needed to reduce the oxygen content in an electrochemical plating bath solution in order to prevent or at least reduce the formation of bubble-induced defects in a metal film or line electroplated onto a wafer.
- In accordance with these and other objects and advantages, the present invention is generally directed to a novel method, which is suitable to substantially reduce the presence of oxygen micro-bubbles in an electroplating bath solution. The method includes the addition of aerobic bacteria to the electroplating bath solution to consume oxygen in the solution. Reduction of the oxygen content in the electroplating bath solution prevents oxygen micro-bubbles from forming in the solution and becoming trapped between the solution and the surface of a metal seed layer on a substrate to block the electroplating of a metal film onto the seed layer. Consequently, the presence of surface pits and other structural defects in the surface of the electroplated metal film is substantially reduced.
- The present invention is further directed to a metal film having a substantially reduced number of surface pits, voids and other defects. The metal film is plated onto a substrate by providing an electrochemical plating solution, adding aerobic bacteria to the solution, immersing the substrate in the solution, and carrying out an electroplating process in the solution.
- The invention will be better understood, by way of example, with reference to the accompanying drawings, in which:
-
FIG. 1 is a schematic of an electrochemical plating system in implementation of the present invention; -
FIG. 1A is a cross-sectional view of a wafer substrate with a metal film electroplated thereon according to the method of the present invention; -
FIG. 2 is a flow diagram illustrating a typical flow of process steps carried out according to the method of the present invention; and -
FIG. 3 is a graph in which the concentration of dissolved oxygen (DO) in an electroplating bath solution to which aerobic bacteria have been added is compared to the concentration of dissolved oxygen in an electroplating bath solution devoid of aerobic bacteria. - The present invention has particularly beneficial utility in the electrochemical plating of a high-quality copper film on a copper seed layer deposited on a semiconductor wafer substrate in the fabrication of semiconductor integrated circuits. However, the invention is more generally applicable to the electrochemical plating of metals including but not limited to copper on substrates in a variety of industrial applications including but not limited to semiconductor fabrication.
- The present invention is generally directed to a novel method for substantially reducing the presence of oxygen micro-bubbles in an electroplating bath solution used to electroplate a metal film on a seed layer provided on a substrate. The method facilitates the electroplating of a metal film which is substantially devoid of voids and surface pits onto the seed layer. According to the method, an aerobic bacteria is added to the electroplating bath solution. The aerobic bacteria consumes all or most of the oxygen in the solution to prevent or reduce the formation of oxygen micro-bubbles in the solution typically as the solution is circulated through the bath container. Consequently, micro-bubble blockage of metal electroplated onto the seed layer is prevented or at least substantially reduced.
- The present invention is further directed to a metal film having a substantially reduced number of surface pits, voids and other defects. The metal film is plated onto a substrate by providing an electrochemical plating solution, adding aerobic bacteria to the solution, immersing the substrate in the solution, and carrying out an electroplating process in the solution.
- The method of the present invention may be used with any formulation for the electrochemical plating bath solution, such as copper, aluminum, nickel, chromium, zinc, tin, gold, silver, lead and cadmium electrochemical plating baths. The present invention is also suitable for use with electrochemical plating baths containing mixtures of metals to be plated onto a substrate.
- It is preferred that the electroplating bath be a copper alloy electroplating bath, and more preferably, a copper electroplating bath. Typical copper electroplating bath formulations are well known to those skilled in the art and include, but are not limited to, an electrolyte and one or more sources of copper ions. Suitable electrolytes include, but are not limited to, sulfuric acid, acetic acid, fluoroboric acid, methane sulfonic acid, ethane sulfonic acid, trifluormethane sulfonic acid, phenyl sulfonic acid, methyl sulfonic acid, p-toluenesulfonic acid, hydrochloric acid, phosphoric acid and the like. The acids are typically present in the bath in a concentration in the range of from about 1 to about 300 g/L. The acids may further include a source of halide ions such as chloride ions.
- Suitable sources of copper ions include, but are not limited to, copper sulfate, copper chloride, copper acetate, copper nitrate, copper fluoroborate, copper methane sulfonate, copper phenyl sulfonate and copper p-toluene sulfonate. Such copper ion sources are typically present in a concentration in the range of from about 10 to about 300 g/L of electroplating solution.
- Aerobic bacteria which are suitable for implementation of the present invention include nitrifying bacterial agents, Bdellovibrio bacteriovorus, Acinetobacter calcoaceticus, Pseudamonas fluorescens, Arthrobacter globiformis, and Acetobacter pasteurianus. In a preferred embodiment of the present invention, the aerobic bacteria is a nitrifying bacterial agent. Preferably, the aerobic bacteria are present in the electroplating bath solution in a concentration of from typically about 1 ml/l to about 5 ml/l.
- Other electrochemical plating process conditions suitable for implementation of the present invention include a plating rpm of from typically about 0 rpm to about 500 rpm; a plating current of from typically about 0.2 mA/cm2 to about 20 mA/cm2; and a bath temperature of from typically about 10 degrees C. to about 35 degrees C. In cases in which planarity of the electroplated metal through chemical mechanical planarization (CMP) is necessary, a leveling agent may be added to the electroplating bath solution at a concentration of from typically about 5 mmol/L to about 5 mol/L.
- Referring to
FIG. 1 , an electrochemical plating (ECP)system 10 which is suitable for implementation of the present invention is shown. Thesystem 10 may be conventional and includes a standard electroplating cell having an adjustablecurrent source 12, abath container 14, a typicallycopper anode 16 and acathode 18, whichcathode 18 is the semiconductor wafer substrate that is to be electroplated with copper. Theanode 16 and cathode/substrate 18 are connected to thecurrent source 12 by means ofsuitable wiring 38. Thebath container 14 holds an electrolyte electroplatingbath solution 20. Thesystem 10 may further include a mechanism for rotating thesubstrate 18 in thebath 20 during the electroplating process, as is known by those skilled in the art. - The
ECP system 10 may further include a pair ofbypass filter conduits 24, a bypass pump/filter 30, and anelectrolyte holding tank 34. Thebypass filter conduits 24 typically extend through theanode 16 and open to the upper, oxidizingsurface 22 of theanode 16 at opposite ends of theanode 16. Thebypass filter conduits 24 connect to the bypass pump/filter 30 located outside thebath container 14, and the bypass pump/filter 30 is further connected to theelectrolyte holding tank 34 through atank inlet line 32. Theelectrolyte holding tank 34 is, in turn, connected to thebath container 14 through atank outlet line 36. It is understood that theECP system 10 heretofore described represents just one example of a possible system which is suitable for implementation of the present invention, and other systems of alternative design may be used instead. - Referring to
FIGS. 1 , 1A and 2, according to the method of the present invention, ametal seed layer 19, such as copper, is deposited on awafer substrate 18, as indicated in step S1 ofFIG. 2 . Themetal seed layer 19 may be deposited on thesubstrate 18 using conventional chemical vapor deposition (CVD) or physical vapor deposition (PVD) techniques, for example, according to the knowledge of those skilled in the art. Theseed layer 19 has a thickness of typically about 50˜1500 angstroms. - As indicated in step S2 of
FIG. 2 , the electrochemical plating (ECP)electrolyte bath solution 20 is prepared in thebath container 14. Theelectroplating bath solution 20 may include an accelerator having a concentration of from typically about 5 mmol/L to about 5 mol/L, and may include a leveling agent or additive in a concentration of from typically about 5 mmol/L to about 5 mol/L, as heretofore noted. - Next, as indicated in step S3 and shown in
FIG. 1 , theaerobic bacteria 25 of the present invention is added to theelectroplating bath solution 20, which is then circulated from thebath container 14, through theelectrolyte holding tank 34 and back to thebath container 14, by operation of thepump 30, to achieve an aerobic bacteria concentration of from typically about 1 ml/l to typically about 5 ml/l in theelectroplating bath solution 20. Theanode 16 andsubstrate 18 are then immersed in thebath solution 20 and connected to the adjustablecurrent source 12, typically throughwiring 38. Accordingly, theseed layer 19 on thesubstrate 18 contacts thebath solution 20. The entire surface of theseed layer 19, as well as gap features on thesubstrate 18, is thoroughly wetted by thebath solution 20. - As indicated in step S4 of
FIG. 2 , thebath 20 is continually circulated from thebath container 14 through thebypass filter conduits 24,electrolyte holding tank 34 and back into thebath container 14, respectively, by operation of thepump 30. This maintains the copper sulfate or other electrolyte in a dissolved state in theelectroplating bath solution 20, and prevents or minimizes precipitation of the electrolyte onto the sides, bottom and other surfaces of thebath container 14, throughout the electroplating process. - During circulation of the
bath solution 20 throughout theECP system 10, as heretofore described, dissolved oxygen normally forms oxygen micro-bubbles (not shown) in thebath solution 20. Accordingly, theaerobic bacteria 25, having been previously added to thebath solution 20 at step S3 ofFIG. 2 , consume all or most of the oxygen present in thebath solution 20. This eliminates or substantially reduces the quantity of oxygen micro-bubbles which form in thesolution 20. Consequently, the presence of micro-bubbles between thebath solution 20 and theseed layer 19 on thesubstrate 18 is eliminated or substantially reduced during the subsequent electroplating process, which will be hereinafter described. - As the
electroplating bath solution 20 is circulated through thesystem 10, ametal film 21 is electroplated onto theseed layer 19, as shown inFIG. 1A and indicated in step S5 ofFIG. 2 , typically as follows. Theelectroplating bath solution 20 is maintained at a temperature of from typically about 10 degrees C. to about 35 degrees C. The plating rpm for thesubstrate 18 is typically about 0-500 rpm. - During the electrochemical plating process, the
current source 12 applies a selected voltage potential, typically at room temperature, between theanode 16 and the cathode/substrate 18. This voltage potential creates a magnetic field around theanode 16 and the cathode/substrate 18, which magnetic field affects the distribution of the copper ions in thebath solution 20. In a typical copper electroplating application, a voltage potential of about 2 volts may be applied for about 2 minutes, and a plating current of from typically about 0.2 mA/cm2 to about 20 mA/cm2 flows between theanode 16 and the cathode/substrate 18. - Consequently, copper is oxidized typically at the oxidizing
surface 22 of theanode 16 as electrons harvested from thecopper anode 16 flow through thewiring 38 and reduce the ionic copper in the typically copper sulfatesolution bath solution 20 to form a copper electroplate (not illustrated) at the interface between the cathode/substrate 18 and thecopper sulfate bath 20. Due to the absence or paucity of oxygen micro-bubbles between thebath solution 20 and the surface of theseed layer 19, the electroplatedmetal film 21 deposited onto theseed layer 19 is substantially continuous and devoid of structural deformities such as voids, pits and broken metal lines. Accordingly, the electroplatedmetal film 21 on thesubstrate 18 contributes to the fabrication of high-quality IC devices that are characterized by high structural and operational integrity. - Referring next to the graph of
FIG. 3 , which illustrates a graph in which the concentration of dissolved oxygen (DO) in an electroplating bath solution to which aerobic bacteria have been added is compared to the concentration of dissolved oxygen in an electroplating bath solution devoid of aerobic bacteria. From a consideration of the graph, it can be seen that the addition of aerobic bacteria to an electroplating bath solution is capable of reducing the concentration of dissolved oxygen (DO) in the solution from about 5 mg/l to about 2 mg/l. - While the preferred embodiments of the invention have been described above, it will be recognized and understood that various modifications can be made in the invention and the appended claims are intended to cover all such modifications which may fall within the spirit and scope of the invention.
Claims (16)
1. A method of electroplating a thin film onto a substrate, comprising:
providing an electroplating bath solution;
providing aerobic bacteria in said solution;
providing a current source in electrical contact with said substrate;
immersing said substrate in said solution; and
plating the thin film onto said substrate by applying a current to said substrate.
2. The method of claim 1 wherein said aerobic bacteria is a nitrifying bacterial agent, Bdellovibrio bacteriovorus, Acinetobacter calcoaceticus, Pseudamonas fluorescens, Arthrobacter globiformis, or Acetobacter pasteurianus.
3. The method of claim 1 wherein said solution comprises copper sulfate.
4. The method of claim 3 wherein said aerobic bacteria is a nitrifying bacterial agent, Bdellovibrio bacteriovorus, Acinetobacter calcoaceticus, Pseudamonas fluorescens, Arthrobacter globiformis, or Acetobacter pasteurianus.
5. The method of claim 1 wherein said aerobic bacteria is present in said solution in a concentration of about 1 ml/l to 5 ml/l.
6. The method of claim 5 wherein said aerobic bacteria is a nitrifying bacterial agent, Bdellovibrio bacteriovorus, Acinetobacter calcoaceticus, Pseudamonas fluorescens, Arthrobacter globiformis, or Acetobacter pasteurianus.
7. The method of claim 5 wherein said solution comprises copper sulfate.
8. The method of claim 7 wherein said aerobic bacteria is a nitrifying bacterial agent, Bdellovibrio bacteriovorus, Acinetobacter calcoaceticus, Pseudamonas fluorescens, Arthrobacter globiformis, or Acetobacter pasteurianus.
9. A method for forming a metal film onto a substrate by:
providing an electroplating bath solution comprising a metal;
providing aerobic bacteria in a concentration of from about 1 ml/l to about 5 ml/l;
providing a current source in electrical contact with said substrate;
immersing said substrate in said solution; and
applying a current of from about 0.2 mA/cm2 to about 20 mA/cm2 to said substrate.
10. The metal film of claim 9 wherein said aerobic bacteria is a nitrifying bacterial agent, Bdellovibrio bacteriovorus, Acinetobacter calcoaceticus, Pseudamonas fluorescens, Arthrobacter globiformis, or Acetobacter pasteurianus.
11. The metal film of claim 9 wherein said electroplating bath solution comprises copper sulfate.
12. An electrochemical plating solution comprising:
an electrolyte solution comprising metal; and
an aerobic bacteria provided in said electrolyte solution.
13. The electrochemical plating solution of claim 12 wherein said metal is copper, aluminum, nickel, chromium, zinc, tin, gold, silver, lead, or cadmium.
14. The electrochemical plating solution of claim 12 wherein said aerobic bacteria is a nitrifying bacterial agent, Bdellovibrio bacteriovorus, Acinetobacter calcoaceticus, Pseudamonas fluorescens, Arthrobacter globiformis, or Acetobacter pasteurianus.
15. The electrochemical plating solution of claim 12 wherein said aerobic bacteria is present in said electroplating bath solution in a concentration of about 1 ml/l to 5 ml/l.
16. The electrochemical plating solution of claim 12 wherein said electroplating bath solution comprises copper sulfate.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11/523,135 US20080067076A1 (en) | 2006-09-19 | 2006-09-19 | Method of reducing oxygen content in ECP solution |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11/523,135 US20080067076A1 (en) | 2006-09-19 | 2006-09-19 | Method of reducing oxygen content in ECP solution |
Publications (1)
Publication Number | Publication Date |
---|---|
US20080067076A1 true US20080067076A1 (en) | 2008-03-20 |
Family
ID=39187437
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/523,135 Abandoned US20080067076A1 (en) | 2006-09-19 | 2006-09-19 | Method of reducing oxygen content in ECP solution |
Country Status (1)
Country | Link |
---|---|
US (1) | US20080067076A1 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20190093252A1 (en) * | 2017-09-22 | 2019-03-28 | Ming Chi University Of Technology | Electroplating apparatus |
US20210125902A1 (en) * | 2019-03-25 | 2021-04-29 | Texas Instruments Incorporated | Semiconductor device with metal die attach to substrate with multi-size cavity |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6113771A (en) * | 1998-04-21 | 2000-09-05 | Applied Materials, Inc. | Electro deposition chemistry |
US6923914B2 (en) * | 1996-12-17 | 2005-08-02 | Global Biosciences, Inc. | Remediation of metal contaminants with hydrocarbon-utilizing bacteria |
-
2006
- 2006-09-19 US US11/523,135 patent/US20080067076A1/en not_active Abandoned
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6923914B2 (en) * | 1996-12-17 | 2005-08-02 | Global Biosciences, Inc. | Remediation of metal contaminants with hydrocarbon-utilizing bacteria |
US6113771A (en) * | 1998-04-21 | 2000-09-05 | Applied Materials, Inc. | Electro deposition chemistry |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20190093252A1 (en) * | 2017-09-22 | 2019-03-28 | Ming Chi University Of Technology | Electroplating apparatus |
US20210125902A1 (en) * | 2019-03-25 | 2021-04-29 | Texas Instruments Incorporated | Semiconductor device with metal die attach to substrate with multi-size cavity |
US11908776B2 (en) * | 2019-03-25 | 2024-02-20 | Texas Instruments Incorporated | Semiconductor device with metal die attach to substrate with multi-size cavity |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Dow et al. | Microvia filling by copper electroplating using diazine black as a leveler | |
US7964506B1 (en) | Two step copper electroplating process with anneal for uniform across wafer deposition and void free filling on ruthenium coated wafers | |
KR102509652B1 (en) | Pretreatment of nickel and cobalt liners for electrodeposition of copper into through silicon vias | |
US6024856A (en) | Copper metallization of silicon wafers using insoluble anodes | |
US7316772B2 (en) | Defect reduction in electrodeposited copper for semiconductor applications | |
Takahashi | Electroplating copper onto resistive barrier films | |
US7799684B1 (en) | Two step process for uniform across wafer deposition and void free filling on ruthenium coated wafers | |
US8377824B1 (en) | Methods and apparatus for depositing copper on tungsten | |
US20040222100A1 (en) | Process and system for providing electrochemical processing solution with reduced oxygen and gas content | |
US8703615B1 (en) | Copper electroplating process for uniform across wafer deposition and void free filling on ruthenium coated wafers | |
WO2007111676A2 (en) | Method of direct plating of copper on a substrate structure | |
CN101016638A (en) | Method for direct electroplating of copper onto a non-copper plateable layer | |
US20060199381A1 (en) | Electro-chemical deposition apparatus and method of preventing cavities in an ecd copper film | |
US8277619B2 (en) | Apparatus for electrochemical plating semiconductor wafers | |
US8268155B1 (en) | Copper electroplating solutions with halides | |
Landau | Copper metallization of semiconductor interconnects-issues and prospects | |
US20050199507A1 (en) | Chemical structures and compositions of ECP additives to reduce pit defects | |
US20080067076A1 (en) | Method of reducing oxygen content in ECP solution | |
US20060191784A1 (en) | Methods and systems for electroplating wafers | |
CN100419129C (en) | Electrolyte for copper plating | |
US7544281B2 (en) | Uniform current distribution for ECP loading of wafers | |
JPH11274107A (en) | Copper plating method and aqueous copper plating agent | |
US20030188974A1 (en) | Homogeneous copper-tin alloy plating for enhancement of electro-migration resistance in interconnects | |
US20050189233A1 (en) | ECP polymer additives and method for reducing overburden and defects | |
JPH11269693A (en) | Deposition method of copper and copper plating liquid |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: TAIWAN SEMICONDUCTOR MANUFACTURING CO. LTD., TAIWA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:CHENG, MING-YUAN;FENG, HSIEN-PING;CHENG, HSI-KUEI;AND OTHERS;REEL/FRAME:018321/0892 Effective date: 20060904 |
|
STCB | Information on status: application discontinuation |
Free format text: EXPRESSLY ABANDONED -- DURING EXAMINATION |