Modular System for Continuous Deposition of a Thin Film Layer on a Substrate

Abstract

A system and associated process for vapor deposition of a thin film layer on a photovoltaic (PV) module substrate is includes establishing a vacuum chamber and introducing the substrates individually into the vacuum chamber. A conveyor system is operably disposed within the vacuum chamber and is configured for conveying the substrates in a serial arrangement through a vapor deposition apparatus within the vacuum chamber at a controlled constant linear speed. A post-heat section is disposed within the vacuum chamber immediately downstream of the vapor deposition apparatus in the conveyance direction of the substrates. The post-heat section is configured to maintain the substrates conveyed from the vapor deposition apparatus in a desired heated temperature profile until the entire substrate has exited the vapor deposition apparatus.

What is claimed is: 
     
         1 . A system for vapor deposition of a thin film layer on photovoltaic (PV) module substrates, comprising:
 a vacuum chamber, said vacuum chamber further comprising a vapor deposition apparatus configured for depositing a thin film of a sublimed source material onto an upper surface of substrates conveyed therethrough;   a conveyor system operably disposed within said vacuum chamber and configured for conveying the substrates in a serial arrangement through said vapor deposition apparatus at a controlled constant linear speed; and,   a post-heat section disposed within said vacuum chamber immediately downstream of said vapor deposition apparatus in the conveyance direction of the substrates, said post-heat section configured to maintain the substrates conveyed from said vapor deposition apparatus in a desired heated temperature profile until the entire substrate has exited said vapor deposition apparatus.   
     
     
         2 . The apparatus as in  claim 1 , wherein said post-heat section is configured to heat the substrates with a temperature profile such that a substantially uniform temperature is maintained along the length of the substrates until the entire substrate is conveyed out of said vapor deposition apparatus. 
     
     
         3 . The apparatus as in  claim 2 , further comprising a cool-down section downstream of said post-heat section in a direction of conveyance of the substrates, said conveyor system configured to convey the substrates through said vapor deposition apparatus and into said post-heat section at a first conveyance rate, and from said post-heat section and into said cool-down section at a substantially greater second conveyance rate effective to prevent a thermal gradient from being established along the length of the substrates. 
     
     
         4 . The apparatus as in  claim 3 , wherein the first conveyance rate is from about 10 mm/sec to about 40 mm/sec, and the second conveyance rate is from about 200 mm/sec to about 600 mm/sec. 
     
     
         5 . The apparatus as in  claim 1 , wherein said post-heat section is configured to heat the substrates with a temperature profile such that a controlled gradually decreasing temperature gradient is established along the length of the substrates until the entire substrate is conveyed out of said vapor deposition apparatus. 
     
     
         6 . The apparatus as in  claim 5 , wherein said post-heat section comprises a module having separately controlled heating zones, and wherein said post-heat module is maintainable at a temperature of from about 400 degrees C. to about 600 degrees C. at an inlet thereof and decreasing to about 200 degrees C. to about 500 degrees C. at an outlet thereof. 
     
     
         7 . The apparatus as in  claim 5 , further comprising a cool-down section downstream of said post-heat module in a direction of conveyance of the substrates, said conveyor system configured to convey the substrates through said vapor deposition apparatus, into and through the post-heat module, and into and through the cool-down section at substantially the same constant liner speed.