Method for making thin film devices intended for solar cells or silicon-on-insulator (SOI) applications

Abstract

In one inventive aspect, a thin film device is manufactured by (a) forming a porous semiconductor layer in the form of a thin film on an original substrate, the formation being immediately followed by (b) separation of the thin film by a lift-off process from the original substrate; (c) transfer of the thin film to a dummy support, the thin film not being attached to the dummy support; (d) fabrication of a device on top of the thin film; and (e) transfer and attachment of said device on said thin film on a foreign substrate.

1 . A system for fabricating a thin film device comprising: 
 an apparatus for transferring a thin semiconductor layer to a dummy substrate, the thin semiconductor layer not being attached to the dummy substrate; and    an apparatus configured to fabricate a device on the thin semiconductor layer after the thin semiconductor layer is transferred to the dummy substrate.    
   
   
       2 . The system of  claim 1 , further comprising an apparatus for forming the thin semiconductor layer on a substrate so that the thin semiconductor layer is free-standing on the substrate.  
   
   
       3 . The system according to  claim 2 , further comprising an apparatus configured to separate the thin semiconductor layer from the substrate.  
   
   
       4 . The system of  claim 1 , wherein the fabricating apparatus fabricates an epitaxial silicon layer on the thin semiconductor layer.  
   
   
       5 . The system of  claim 1 , wherein the apparatus configured to fabricate a device is adapted for fabricating a first device on a first side of the thin semiconductor layer and for fabricating a second device on a second side of the thin semiconductor layer.  
   
   
       6 . The system of  claim 1 , wherein the apparatus configured to fabricate a device is adapted for fabricating at least one of a front and a back side of a solar cell on the thin semiconductor layer.  
   
   
       7 . The system of  claim 1 , wherein the fabricating apparatus deposits an active semiconductor layer on the thin semiconductor layer.  
   
   
       8 . The system according to  claim 7 , wherein deposition of the active semiconductor layer is performed by epitaxial Chemical Vapor Deposition.  
   
   
       9 . The system of  claim 1 , further comprising an apparatus for transferring the thin semiconductor layer, comprising the device, to a foreign substrate.  
   
   
       10 . The system of  claim 9 , further comprising an apparatus for bonding the thin semiconductor layer to the foreign substrate.  
   
   
       11 . The system of  claim 1 , wherein the device is a non-finished device that is further finished after attachment to a foreign substrate.  
   
   
       12 . The system of  claim 1 , wherein the thin semiconductor layer is separated from the substrate by immersing the substrate in a HF solution in concentration between about 12 and 35% and using current densities between about 50 and 250 mA/cm 2 .  
   
   
       13 . The system of  claim 1 , wherein the thin semiconductor layer is a double layer of crystalline or amorphous semiconductor material including silicone germanium, III-V materials such as Ga As, InGaAs and semiconducting polymers.  
   
   
       14 . The system of  claim 9 , wherein the foreign substrate comprises a low-cost substrate.  
   
   
       15 . The system of  claim 1 , wherein the thin film device comprises a solar cell.  
   
   
       16 . The system of  claim 9 , wherein the foreign substrate comprises glass.  
   
   
       17 . A system for manufacturing a thin film device comprising: 
 means for transferring a thin semiconductor layer to a dummy substrate, the thin semiconductor layer not being attached to the dummy substrate; and    means for fabricating a device on the thin semiconductor layer after being transferred to the dummy substrate.    
   
   
       18 . The system of  claim 17 , further comprising means for forming the thin semiconductor layer on a substrate so that the thin semiconductor layer is free-standing on the substrate.  
   
   
       19 . The system of  claim 18 , further comprising means for separating the thin semiconductor layer from the substrate.  
   
   
       20 . The system of  claim 17 , further comprising means for attaching the device and the thin semiconductor layer on a foreign substrate.  
   
   
       21 . The system of  claim 17 , further comprising means for bonding the thin semiconductor layer to the foreign substrate.  
   
   
       22 . The system of  claim 17 , wherein the fabricating means comprises means for fabricating an epitaxial silicon layer.  
   
   
       23 . The system of  claim 17 , wherein the fabricating means is adapted for fabricating a first device on a first side of the thin semiconductor layer and for fabricating a second device on a second side of the thin semiconductor layer.  
   
   
       24 . The system of  claim 17 , wherein the fabricating means is adapted for fabricating at least one of a front and a back side of a solar cell on the thin semiconductor layer.  
   
   
       25 . The system of  claim 17 , wherein the fabricating means deposits an active semiconductor layer on the thin semiconductor layer.  
   
   
       26 . The system according to  claim 25 , wherein deposition of the active semiconductor layer is performed by epitaxial Chemical Vapor Deposition.  
   
   
       27 . The system of  claim 17 , wherein the device is a non-finished device that is further finished after attachment to a foreign substrate.  
   
   
       28 . The system of  claim 17 , wherein the thin semiconductor layer is separated from the substrate by immersing the substrate in a HF solution in concentration between about 12 and 35% and using current densities between about 50 and 250 mA/cm 2 .  
   
   
       29 . The system of  claim 1 , wherein the thin semiconductor layer is a porous semiconductor layer.  
   
   
       30 . The system of  claim 17 , wherein the thin semiconductor layer is a porous semiconductor layer.  
   
   
       31 . The system of  claim 1 , further comprising means for clamping the thin semiconductor layer on the dummy substrate.  
   
   
       32 . The system of  claim 17 , further comprising means for clamping the thin semiconductor layer on the dummy substrate.  
   
   
       33 . A system for fabricating a thin film device, the system being configured to form a thin semiconductor layer on a substrate so that the thin semiconductor layer is free-standing on the substrate, separate the thin semiconductor layer from the substrate, and fabricate a device on the thin semiconductor layer after the thin semiconductor layer is separated from the substrate.