Apparatus and method for electroless deposition of materials on semiconductor substrates

• US 20030181040A1
• Filed: 03/22/2002
• Published: 09/25/2003
• Est. Priority Date: 03/22/2002
• Status: Active Grant

• Current Assignee: Lam Research Corporation
• Original Assignee: Blue 29, LLC
• Inventors: Kolics, Artur, Ivanov, Igor, Zhang, Jonathan Weiguo
• Granted Patent: US 6,913,651 B2
• Time in Patent Office: Days
• US Class Current: 438/687
• CPC Class Codes: C23C 18/1628 Specific elements or parts of the apparatus
• CPC Class Codes: C23C 18/163 Supporting devices for articles to be coated
• CPC Class Codes: C23C 18/1632 Features specific for the apparatus, e.g. layout of cells and of its equipment, multiple cells
• CPC Class Codes: C23C 18/1676 Heating of the solution
• CPC Class Codes: C23C 18/168 Control of temperature, e.g. temperature of bath, substrate
• CPC Class Codes: C23C 18/1682 Control of atmosphere
• CPC Class Codes: H01L 21/288 from a liquid, e.g. electrolytic deposition

Abstract

An apparatus of the invention has a closable chamber that can be sealed and is capable of withstanding an increased pressure and high temperature. The chamber contains a substrate holder that can be rotated around a vertical axis, and an edge-grip mechanism inside the substrate holder. The deposition chamber has several inlet ports for the supply of various process liquids, such as deposition solutions, DI water for rinsing, etc., and a port for the supply of a gas under pressure. The apparatus is also provided with reservoirs and tanks for processing liquids and gases, as well as with a solution heater and a control system for controlling temperature and pressure in the chamber. The heater can be located outside the working chamber or built into the substrate holder, or both heaters can be used simultaneously. Uniform deposition is achieved by carrying out the deposition process under pressure and under temperature slightly below the boiling point of the solution. The solution can be supplied from above via a shower head formed in the cover, or through the bottom of the chamber. Rinsing or other auxiliary solutions are supplied via a radially moveable chemical dispensing arm that can be arranged above the substrate parallel thereto.

Claims

1. A method for electroless deposition of a material in the form a thin film of said material on a substrate from a deposition solution in a working chamber of an electroless deposition apparatus, comprising:

placing said substrate into said apparatus;

supplying said deposition solution into said apparatus;

generating a predetermined pressure in said apparatus;

heating said deposition solution in said apparatus to a working temperature which is below the boiling point of said solution under said predetermined pressure;

conducting said electroless deposition;

constantly maintaining said working temperature below said boiling point during said electroless deposition;

and discontinuing said electroless deposition when said thin film reaches a predetermined thickness.

2. The method of claim 1, wherein said temperature below the boiling point is within the range from 0 to 25% below the boiling point of said deposition solution at said predetermined pressure.

3. The method of claim 2, further comprising the step of forming an additional closed space which is smaller than said working chamber and is located inside said working chamber, said electroless deposition being carried out in said additional closed space.

4. The method of claim 3, wherein said step of supplying is carried out from above said substrate through a shower-head manifold having a plurality of outlet openings.

5. The method of claim 3, wherein said step of supplying is carried through the bottom of said working chamber.

6. An apparatus for electroless deposition of a material from a deposition solution in the form of a thin film onto a substrate, comprising:

a sealable working chamber having an interior and a removable cover, said removable cover having an inner side that faces said interior;

a substrate holder in said sealable working chamber, said substrate holder having a substrate grip mechanism rotatingly and slidingly installed inside said substrate holder;

first solution supply means for supplying at least one deposition solution into said sealable working chamber, said deposition solution having a predetermined boiling point at a predetermined working pressure;

rotating means for rotating said substrate grip mechanism in said sealable working chamber around an axis of rotation;

moving means for moving said substrate grip mechanism in the direction of said axis of rotation;

heating means for heating said deposition solution in order to maintain said deposition solution in a heated state in said at least one sealable working chamber;

temperature control means for controlling said working temperature of said deposition solution;

pressure means for changing a working pressure inside said sealable working chamber; and

a pressure control means for maintaining said working pressure inside said sealable working chamber at a value that maintains said deposition solution at a temperature below said predetermined boiling point.

7. The apparatus of claim 6, wherein said heating control means maintain said working temperature at a level from 0 to 25% below said predetermined boiling point.

8. The apparatus of claim 6, further comprising cover moving means for moving said cover towards to and away from said working chamber, said working chamber having a bottom and being further provided with a cup-shaped cover support which is open upward and being rigidly attached to said bottom, said cover having a tapered edge, said cup-shaped cover support having tapered edge engageable with said tapered edge of said cover when said cover is moved towards said working chamber by said cover moving means and form a closed space with said cover support, said substrate holder with said substrate grip being located in said closed space.

9. The apparatus of claim 8, further comprising a deposition solution tank that contains said deposition solution, said first solution supply means comprise a shower-head manifold located on said inner side of said removable cover and having a plurality of outlet openings, and a pump for the supply of said deposition solution from said solution tank to said shower-head manifold.

10. The apparatus of claim 9, further comprising auxiliary solution feeding means and rinsing medium feeding means, and a dispensing arm moveable between a position outside said working chamber and a position in which said dispensing arm is located in said closed space and is arranged above and parallel to said substrate in said substrate holder, and valve means for selectively connecting said dispensing arm with said auxiliary solution feeding means and rinsing medium feeding means.

11. The apparatus of claim 6, wherein said rotating means comprise a hollow shaft having a central through opening and rigidly connected to said substrate holder and sealingly projecting outside said working chamber, and driver means for rotating said hollow shaft.

12. The apparatus of claim 10, wherein said rotating means comprise a hollow shaft having a central through opening and rigidly connected to said substrate holder and sealingly projecting outside said working chamber, and driver means for rotating said hollow shaft.

13. The apparatus of claim 6, wherein said moving means comprise:

a shaft slidingly and sealingly inserted into said interior of said working chamber through said rotating means and having one end rigidly connected to said substrate grip mechanism and the other end projecting outside said sealable working chamber; and

a linear drive means connected to said shaft.

14. The apparatus of claim 12, wherein said moving means comprise:

a shaft slidingly inserted into said central through opening and having one end rigidly connected to said edge-grip mechanism inside said closed space and the other end projecting outside said sealable working chamber; and

a linear drive means connected to said shaft.

15. The apparatus of claim 6, wherein said working chamber has a bottom and is further provided with second solution supply means for the supply of said deposition solution into said working chamber through said bottom.

16. The apparatus of claim 6, wherein said working chamber has a bottom, said apparatus being further provided with second solution supply means for the supply of said deposition solution into said working chamber through said bottom.

17. The apparatus of claim 8, further provided with second solution supply means for the supply of said deposition solution into said closed space through said bottom.

18. The apparatus of claim 6, wherein said heating means is a heater located outside said working chamber in said solution supply means.

19. The apparatus of claim 13, wherein said heating means is a heater located outside said working chamber in said solution supply means.

20. The apparatus of claim 14, wherein said heating means is a first heater located outside said working chamber in said solution supply means.

21. The apparatus of claim 6, wherein said heating means is heater located inside said working chamber and built-in into said substrate holder.

22. The apparatus of claim 18, wherein said heating means is further provided with a second heater located inside said working chamber and built-in into said substrate holder.