METHOD OF MANUFACTURING SILICON p-i-n PHOTODIODE Russian patent published in 2014 - IPC H01L31/18 

FIELD: chemistry.

SUBSTANCE: invention relates to technology of manufacturing silicon p-i-n photodiodes (FD), sensitive to radiation with wavelengths 0.9-1.06 mcm. According to invention in method of manufacturing silicon p-i-n photodiodes, in order to reduce concentration of electrically active centres, created by contaminating admixtures with low values of diffusion coefficients, process of thermal oxidation is carried out at temperature not higher than 950°C and the following processes of diffusion (phosphorus diffusion to create n+-regions, gettering with diffusion n+- layer, boron diffusion to create p+-region) are performed at temperatures, which do not exceed the given one. In this case due to sharp reduction of diffusion coefficient of admixtures with reduction of temperature of processes (exponential dependence on temperature) mainly admixtures with high diffusion coefficients, which later are efficiently removed by means of gettering processes, penetrate into silicon volume.

EFFECT: reduced concentration of generation-recombination centres in i-region of photodiode, which results in reduction of FD dark current and increased percent of output of usable devices.