Patent ID: 9391231
Filing Date: 2016-07-12
CPC Classification: C23C,H01L,Y02E,Y02P

Claim Text:
1. A method for manufacturing a thin absorber material layer consisting essentially of Cu, Zn, and Sn sulphide(s), with atomic percentages of the three metals Cu, Zn, and Sn which may vary in the interval from x=40 to 60% for Cu, and from y=15 to 35% for Zn, and from z=15 to 35% for Sn, with x+y+z=100%, as a quaternary compound Cu—Zn—Sn—S, designated hereafter as a CZTS compound with large crystal grains of average sizes of at least 500 nm, said thin absorber layer being deposited on layered material(s) forming a substrate, wherein the following successive steps are carried out: 1) a layer is deposited by means of a dispersion of particles, as a liquid or a slurry, all of said particles being nanoparticles, and wherein said nanoparticles consist essentially of a quaternary compound made of Cu, Zn, and Sn sulphide(s) with sizes of less than 500 nm, on a molybdenum layer of the substrate having a thin layer of molybdenum, and 2) an annealing heat treatment of said layer deposited on said substrate is carried out, at a maximum temperature of at least 300° C., in order to obtain crystallization and growth of the nanoparticles in order to obtain large crystal grains of average sizes of at least 500 nm, over a thickness from 0.5 to 5 μm, with said crystal grains placed side-by-side in direct contact with each other, wherein said heat treatment comprises two successive annealing steps in the following different atmospheres, namely: