Capping layers for improved crystallization
US10109755B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 26, 2016 |
| Grant date | Oct 23, 2018 |
| Priority date | — |
| Expiry date | May 26, 2036 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31678
Abstract
Techniques for fabrication of kesterite Cu—Zn—Sn—(Se,S) films and improved photovoltaic devices based on these films are provided. In one aspect, a method of fabricating a kesterite film having a formula Cu2−xZn1+ySn(S1−zSez)4+q, wherein 0≤x≤1; 0≤y≤1; 0≤z≤1; and −1≤q≤1 is provided. The method includes the following steps. A substrate is provided. A bulk precursor layer is formed on the substrate, the bulk precursor layer comprising Cu, Zn, Sn and at least one of S and Se. A capping layer is formed on the bulk precursor layer, the capping layer comprising at least one of Sn, S and Se. The bulk precursor layer and the capping layer are annealed under conditions sufficient to produce the kesterite film having values of x, y, z and q for any given part of the film that deviate from average values of x, y, z and q throughout the film by less than 20 percent.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.