Multi-crystalline ii-vi based multijunction solar cells and modules

Abstract

Multi-crystalline group II-VI solar cells and methods for fabrication of same are disclosed herein. A multi-crystalline group II-VI solar cell includes a first photovoltaic sub-cell comprising silicon, a tunnel junction, and a multi-crystalline second photovoltaic sub-cell. A plurality of the multi-crystalline group II-VI solar cells can be interconnected to form low cost, high throughput flat panel, low light concentration, and/or medium light concentration photovoltaic modules or devices.

We claim: 
     
         1 . A photovoltaic cell module, comprising:
 a frame configured to define an aperture area of the photovoltaic cell module for receiving light; and   a plurality of multi junction solar cells positioned within the frame to receive the light, wherein each of the multi junction solar cells includes:
 a first photovoltaic sub-cell comprising silicon, 
 a tunnel junction provided over the first photovoltaic sub-cell, the tunnel junction including a II-VI semiconductor material layer having a band gap greater than 1.5 eV, and 
 a second photovoltaic sub-cell provided over the tunnel junction, the second photovoltaic sub-cell including a multi-crystalline group II-VI semiconductor material base and a multi-crystalline group II-VI semiconductor material emitter having band gaps greater than 1.5 eV, 
   wherein a total surface area of the plurality of multi junction solar cells for receiving light comprises at least 50% of the aperture area.   
     
     
         2 . The photovoltaic cell module of  claim 1 , wherein the tunnel junction includes a silicon layer provided below the II-VI semiconductor material layer, and wherein the total surface area comprises the total surface area of the multi-crystalline group II-VI semiconductor material emitter across all of the multi junction solar cells. 
     
     
         3 . The photovoltaic cell module of  claim 1 , wherein a total surface area of at least one of the multi-crystalline group II-VI semiconductor material base and the multi-crystalline group II-VI semiconductor material emitter for receiving the light across all of the multi junction solar cells comprises at least 75% of the aperture area. 
     
     
         4 . The photovoltaic cell module of  claim 1 , wherein a total surface area of at least one of the multi-crystalline group II-VI semiconductor material base and the multi-crystalline group II-VI semiconductor material emitter for receiving the light across all of the multi junction solar cells comprises at least 90% of the aperture area.