Semi-insulating silicon carbide mono-crystal

Abstract

A semi-insulating silicon carbide monocrystal and a method of growing the same are disclosed. The semi-insulating silicon carbide monocrystal comprises intrinsic impurities, deep energy level dopants and intrinsic point defects. The intrinsic impurities are introduced unintentionally during manufacture of the silicon carbide monocrystal, and the deep energy level dopants and the intrinsic point defects are doped or introduced intentionally to compensate for the intrinsic impurities. The intrinsic impurities include shallow energy level donor impurities and shallow energy level acceptor impurities. A sum of a concentration of the deep energy level dopants and a concentration of the intrinsic point defects is greater than a difference between a concentration of the shallow energy level donor impurities and a concentration of the shallow energy level acceptor impurities, and the concentration of the intrinsic point defects is less than the concentration of the deep energy level dopants. The semi-insulating SiC monocrystal has resistivity greater than 1×10 5 ©·cm at room temperature, and its electrical performances and crystal quality satisfy requirements for manufacture of microwave devices. The deep energy level dopants and the intrinsic point defects jointly serve to compensate the intrinsic impurities, so as to obtain a high quality semi-insulating single crystal.

Description

technical field [0001] The invention relates to a semi-insulating silicon carbide single crystal, in particular to a semi-insulating silicon carbide substrate used in microwave devices. Background technique [0002] Silicon carbide (SiC) materials have huge applications in high temperature, high frequency, high power, optoelectronics and radiation resistance due to their wide band gap, high critical breakdown electric field, high thermal conductivity, and high carrier saturation drift velocity. prospect. In particular, semi-insulating silicon carbide substrates are widely used in the field of microwave devices. The "semi-insulating" refers to the resistivity at room temperature greater than 10 5 Ω·cm, which is consistent with the conceptual description of "high resistance". Transistors fabricated from semi-insulating silicon carbide are capable of generating more than five times the power density of GaAs microwave components at frequencies up to 10 GHz. Therefore, the man...

AI Technical Summary

Problems solved by technology

However, transition group elements are introduced into silicon carbide crystals as deep energy levels to obtain semi-insulation, which also has some disadvantages

For example, when vanadium is introduced into SiC crystal as a deep-level dopant, the presence of a large amount of vanadium will also introduce corresponding crystal defects. When the concentration of vanadium exceeds its solid solubility limit in SiC crystal (5×10 17 cm -3 ), it will produce vanadium precipitates and micropipes, which will affect the crystallization quality of the crystal

On the other hand, if the doping amount of vanadium is too much, the electron mobility of the crystal will be reduced, which will also affect the performance of the prepared microwave device.

Images