Research of p‐i‐n Junctions Based on 4H‐SiC Fabricated by Low‐Temperature Diffusion of Boron

Abstract

Novel method of boron diffusion at low temperatures between 1150 and 1300°C is used for the formation of both p-i SiC junction and i-region in one technological process. As the junction formation conditions in this method are essentially different from those in the conventional diffusion (low temperatures and process of diffusion are accompanied by formation of structure defects), it is of special interest to identify advantages and disadvantages of a new method of diffusion. Developed SiC p-i-n junction diodes have fast switching time, and the duration of the reverse recovery current is less than 10 ns with a breakdown voltage of 120-140 V. Fabricated diodes possess capability to operate at temperatures up to 300°C. As the temperature of diffusion process is lower than the melting temperature of silicon, this new technology allows fabrication of diodes on the base of SiC/Si epitaxial structures.

ВЛИЯНИЕ ИОНИЗОВАННЫХ ПРИМЕСЕЙ И МИКРОТРУБОК НА ВАХ p-n-4Н-SiC-ПЕРЕХОДА

“…Ранее в работах [6][7][8][9][10][11][12][13][14][15][16][17][18] исследован метод низкотемпературной диффузии мелких примесей в SiC, изготовлены p-n диодные структуры и изучены их электрофизические и оптические характеристики.…”

Spectral Dependence of Optical Absorption of 4H-SiC Doped with Boron and Aluminum

“…We have developed a new low-temperature method for shallow impurities diffusion in silicon carbide at temperatures of 1150-1300°C. e method is described in details in publications [7][8][9][10][11] and patented in Uzbekistan and the USA [12,13]. A significant decrease in temperature is due to the fact that diffusion occurs in the flow of carbon and silicon vacancies.…”

“…Advantages of low-temperature di usion are as follows: shallow impurity concentration of up to 10 20 cm −3 (unreachable for conventional thermal di usion and ion implantation technique), and fast switching time of <10 ns of p-i-n SiC diodes fabricated by this method (>20 ns for diodes fabricated by conventional technology) [10,11].…”