Investigation of the post-growth technique for fabricating multijunction solar sells based on the GaInP/GaAs/Ge heterostructure has been carried out. Investigated were methods of liquid chemical and electro-chemical etching of heterostructure layers. Technology for creating the separation mesa-structure has been developed. The improvement of the surface quality and of the profile of the mesa lateral side for heterostructures of different layer content has been achieved.

Investigation and development of the post-growth technology for fabricating multi-junction photovoltaic converters based on GaInP/GaInAs/Ge heterostructure has been carried out. Antireflection coating, ohmic contacts and mesa-structure forming stages have been reviewed. The technology of n+-GaAs contact layer etching with the help of plasma-chemical, liquid and ion-beam etching has been investigated. Antireflection coefficient of radiation from the heterostructure with TiOx/SiO2 (x close to 2) antireflection coating surface was less then 3% in wavelength range 450-850 nm. The value of contact resistance for n- and p-type conductivity was 3E−5 − 3E−6 ohm · cm2, the decrease of photosensitive region shading degree at increased bus-bar conductivity has been archived. The mesa-structure surface current leakage decreased to the value of E-9 A at voltage less then 1 V.

Investigation of the heterostructure plasmachemical etching technology for fabricating multi-junction photovoltaic converters has been carried out. The dividing mesa-structure forming stage at different etching regimes and subsequent disturbed layer removing by liquid chemical treatment has been reviewed. The influence of mesa etching methods on cells photovoltaic characteristics has been investigated. Developed was the technology of photovoltaic converters fabrication with low current leakage values less than 10-9 A at voltage less then 1 V with high resistance to degradation.

Investigations and modeling of ohmic contacts electrochemical deposition process in postgrowth technology of photovoltaic converters fabrication have been carried out. The technology of Ag/Au contact system galvanic deposition at vertical and horizontal position of heterostructure and anode in the electrolyte has been developed. The increase of contact system deposition uniformity up to ∼ 95% at the thickness of contact bus-bars ∼ 5 µm on the heterostructure area with 4 inch diameter has been archived.

Investigations of methods for texturing the light-emitting surface of IR light-emitting diodes (LEDs) (wavelength 850 nm) based on AlGaAs/GaAs heterostructures with Bragg reflectors have been carried out. Developed were methods of liquid and plasma-chemical etching of solid solution for creating peaks (pyramids) of different form, 0.2–1.5 µm height. Estimation of the effect of texturing methods and also configuration of peaks on the light-emitting diode electroluminescence intensity has been performed. The increase of the electroluminescence intensity by 25% has been achieved.