METHOD AND SYSTEM FOR LARGE SCALE MANUFACTURE OF THIN FILM PHOTOVOLTAIC DEVICES USING MULTI-CHAMBER CONFIGURATION

• US 20120186975A1
• Filed: 01/24/2012
• Published: 07/26/2012
• Est. Priority Date: 11/14/2007
• Status: Active Grant

• Current Assignee: Stion Corporation
• Original Assignee: Stion Corporation
• Inventors: Lee, Howard W. H., Farris, Chester A. III
• Granted Patent: US 8,501,507 B2
• Time in Patent Office: Days
• US Class Current: 204/192.25
• CPC Class Codes: H01L 21/67167 surrounding a central transfer chamber
• CPC Class Codes: H01L 21/67173 in-line arrangement
• CPC Class Codes: H01L 21/67213 comprising at least one ion or electron beam chamber coating by ion implantation C23C; ion or electron beam tubes H01J37/00
• CPC Class Codes: H01L 21/6723 comprising at least one plating chamber electroless plating apparatuses C23C, electroplating apparatuses C25D
• CPC Class Codes: Y10S 428/917 Electroluminescent

Abstract

A method for large scale manufacture of photovoltaic devices includes loading a substrate into a load lock station and transferring the substrate in a controlled ambient to a first process station. The method includes formation of a first conductor layer overlying the surface region of the substrate. The method includes transferring the substrate to a second process station, and forming a second layer overlying the surface region of the substrate. The method further includes repeating the transferring and processing until all thin film materials of the photovoltaic devices are formed. In an embodiment, the invention also provides a method for large scale manufacture of photovoltaic devices including feed forward control. That is, the method includes in-situ monitoring of the physical, electrical, and optical properties of the thin films. These properties are used to determine and adjust process conditions for subsequent processes.

Claims

1. A system for manufacturing a thin film photovoltaic device, the system comprising:

a load lock station comprising a plurality of interfaces, wherein at least one of the plurality of interfaces provides access to the load lock station from an environment external to the system;

a plurality of process stations configured to perform at least one process associated with a set of processes for forming a thin film photovoltaic device, wherein each process station includes an individually controlled temperature system and individually controlled pressure system to maintain identified operating parameters during the at least one process; and

a plurality of transfer stations, each transfer station mechanically coupled with an interface of the load lock station at a first end of the transfer station, and each of the plurality of transfer stations additionally coupled with one of the plurality of process stations at a second end of the transfer station so that a substrate can be transferred between the load lock station and any of the plurality of process stations via the transfer station associated with that process station.

2. The system of claim 1, wherein the set of processes for forming a thin film photovoltaic device comprise film deposition, patterning, etching, curing, annealing, or cleaning

3. The system of claim 1, wherein the load lock station includes an individually controlled pressure system configured to evacuate the load lock station from an ambient pressure to a vacuum pressure, or there between, and pressurize the load lock station from the vacuum pressure to the ambient pressure, or there between.

4. The system of claim 3, wherein the vacuum pressure is at or below 6.2 mTorr.

5. The system of claim 1, wherein the transfer stations include individually controlled pressure systems operable to maintain a pressure at or between an ambient pressure and a vacuum pressure so that an equivalent pressure can be maintained between the load lock station, a process station, and the associated transfer station.

6. The system of claim 1, wherein each transfer station from the plurality of transfer stations includes individually controlled gas delivery systems configured to provide an inert atmosphere between the load lock station and any of the plurality of process stations by delivering an inert gas to any of the plurality of transfer stations associated with any of the plurality of process stations.

7. The system of claim 1, wherein the load lock station is centrally located among the plurality of process stations so that the plurality of transfer stations extend radially outward from the load lock station to each of the plurality of process stations.

8. The system of claim 1, wherein the plurality of process stations comprises at least five process stations.

9. The system of claim 1, wherein the system is configured to maintain, transfer, and process substrates comprising lateral dimensions of at least two feet by five feet.

10. The system of claim 1, wherein at least one of the plurality of process stations is configured to perform physical vapor deposition via scanning magnetron sputtering, and the sputtering target is at least about five feet wide.

11. The system of claim 1, wherein a first process station from the plurality of process stations is configured to form a copper-indium composite material with a Cu-rich stoichiometry overlying an electrode layer on the substrate.

12. The system of claim 11, wherein a second process station from the plurality of process stations is configured to subject the copper-indium composite material to a thermal process in a sulfur-bearing environment to form a copper-indium-sulfur composite material.

13. The system of claim 12, wherein the thermal process is performed at a temperature of about 500°

C.

14. A method of manufacturing thin film photovoltaic devices, the method comprising:

accessing a substrate housed in a load lock station that has been depressurized from an external ambient pressure to a first internal pressure that is less than the external ambient pressure;

transferring the substrate from the load lock station to a first process station, wherein the substrate is transferred to the first process station via a first transfer station, the first transfer station is mechanically coupled with the load lock station at a first end of the first transfer station, and the first transfer station is mechanically coupled with the first process station at a second end of the first transfer station;

performing a first process for forming a thin film photovoltaic device in the first process station, wherein a first process temperature in the first process station is adjusted using a first process station temperature system, and a first process pressure in the first process station is adjusted using a first process station pressure system;

returning the substrate from the first process station to the load lock station via the first transfer station;

transferring the substrate from the load lock station to a second process station, wherein the substrate is transferred to the second process station via a second transfer station, the second transfer station is mechanically coupled with the load lock station at a first end of the second transfer station, and the second transfer station is mechanically coupled with the second process station at a second end of the second transfer station; and

performing a second process for forming a thin film photovoltaic device in the second process station, wherein a second process temperature in the second process station is adjusted using a second process station temperature system, and a second process pressure in the second process station is adjusted using a second process station pressure system.

15. The method of claim 14, wherein the first transfer station includes a first transfer station pressure system that maintains a first transfer pressure during the transferring of the substrate to the first process station that is equal to the first process pressure.

16. The method of claim 14, wherein the first transfer station includes a first transfer station gas delivery system that delivers an inert gas to the first transfer station and maintains an inert environment in the first transfer station during the transferring of the substrate to the first process station.

17. The method of claim 14, wherein the first process for forming a thin film photovoltaic device comprises film deposition, patterning, etching, curing, annealing, or cleaning.

18. The method of claim 14, further comprising, prior to transferring the substrate from the load lock station to the second process station, adjusting the load lock pressure from the first internal pressure to a second internal pressure that is equal to the second process pressure, and wherein the second transfer station includes a second transfer station pressure system that maintains a second transfer pressure during the transferring of the substrate to the second process station that is equal to the second process pressure.

19. The method of claim 14, further comprising:

transferring the substrate from the load lock station to a third process station, wherein the substrate is transferred to the third process station via a third transfer station, the third transfer station is mechanically coupled with the load lock station at a first end of the third transfer station, and the third transfer station is mechanically coupled with the third process station at a second end of the third transfer station;

performing a third process for forming a thin film photovoltaic device in the third process station, wherein a third process temperature in the third process station is adjusted using a third process station temperature system, and a third process pressure in the third process station is adjusted using a third process station pressure system.

20. The method of claim 19, further comprising, prior to transferring the substrate from the load lock station to the third process station, adjusting the load lock pressure from the second internal pressure to a third internal pressure that is equal to the third process pressure, and wherein the third transfer station includes a third transfer station pressure system that maintains a third transfer pressure during the transferring of the substrate to the third process station that is equal to the third process pressure.

21. The method of claim 20, wherein one of the first process station, the second process station, or the third process station is configured to form a copper-indium composite material with a Cu-rich stoichiometry overlying an electrode layer on the substrate.