METHOD FOR MANUFACTURING A PHOTOCONVERTER ON A THINNED GERMANIUM SUBSTRATE Russian patent published in 2023 - IPC H01L31/18 

FIELD: power engineering.

SUBSTANCE: invention relates to solar energy, in particular, to methods for manufacturing three-stage photoconverters on a germanium substrate. Method for manufacturing a photoconverter on a thinned germanium substrate includes the stages of creating a three-stage structure of a photoresistive mask with windows for the front contacts of the photoconverter and diode on a germanium substrate with grown epitaxial layers; etching a diode pad; spraying on layers of front metallisation; removing the photoresist; creating a photoresistive mask with windows for mesa-insulation of the photoconverter and the diode; etching a mesa; applying a protective coating; performing chemical dynamic etching of the germanium substrate; removing the protective coating; spraying on back metallisation; annealing the contacts; the chemical dynamic etching of the substrate is performed before the hydrofluoric acid used to limit the amount of etched germanium is consumed, wherein the solution of etching products is used multiple times, re-adding hydrofluoric acid and hydrogen peroxide in the ratio of volume parts being hydrofluoric acid (46%) 8÷17 volume parts, hydrogen peroxide (30%) 8÷19 volume parts, solution of etching products 84÷64 volume parts, followed by chemical dynamic treatment of the germanium substrate in a solution of orthophosphoric acid, hydrogen peroxide, and water.

EFFECT: increase in the parameters and the yield of photoconverters manufactured on a thinned germanium substrate, lower costs of recycling etched germanium and disposing of hydrofluoric acid.

1 cl, 5 dwg, 4 tbl