METHOD OF MAKING SILICON PHOTODIODE Russian patent published in 2025 - IPC H10F71/00 

FIELD: electric elements.

SUBSTANCE: invention relates to the technology of manufacturing silicon photodiodes (PD) which are sensitive to radiation with wavelengths of 0.4-1.0 mcm and are made on n-type silicon. They are intended for use in multispectral photodetector devices (PDD), where, along with a silicon photodiode, photodetectors operating in the long-wavelength part of the spectrum (>2 mcm) are used. For use in said devices, a silicon photodiode must provide transmission of said radiation to ensure sensitivity of the following photodetectors. Method of making a silicon photodiode involves processes of thermal oxidation, diffusion of boron to form p⁺-type conductivity regions, diffusion of phosphorus into the front surface of the plate to create contact to the n-region (substrate) and processes of forming ohmic contacts, while reducing absorption of radiation in heavily doped diffusion layers and maintaining a low level of dark currents after performing said thermal processes prior to formation of ohmic contacts, ion implantation of argon with dose of 2⋅10¹⁵ ion/cm² and energy of 100 keV into the back surface of the sample with subsequent annealing of the plates with the formed structures at temperature of 850 °C with slow cooling (<3 K/min).

EFFECT: invention reduces absorption of long-wave infrared radiation in heavily doped diffusion layers of a silicon photodiode to improve parameters of multispectral PDD.

1 cl, 2 dwg