Research progress of large size SiC single crystal materials and devices

Abstract

SiC semiconductor is the focus of recent international research. It is also an important raw material for China to achieve carbon emission peak and carbon neutrality. After nearly 20 years of research and development, we focus on the three types SiC crystals, n-type, p-type and semi-insulating, indicating the development of Shandong University for crystal growth. And defects control, electrical property, atomic polishing, and corresponding device authentication all obtain great progress. Total dislocation density of 6-inch n-type substrates decreases to 2307 cm−2, where BPD (Basal Plane Dislocation) lowers to 333 cm−2 and TSD (Threading Screw Dislocation) 19 cm−2. The full width at half maximum (FWHM) (0004) rocking curves is only 14.4 arcsec. The resistivity reaches more than 1E + 12 Ω·cm for semi-insulating SiC and lower than 20 mΩ·cm for n-type SiC. The impurity concentrations in 6-inch high-purity semi-insulating (HPSI) SiC crystals reach extreme low levels. The devices made of various substrate materials have good performance.

Rapid Growth of High-Purity 3C-SiC Crystals Using a SiC-Saturated Si–Pr–C Solution

“…7 As a result, defects are consistently generated during the process of growing SiC single crystals, compromising device performance and lifespan. 8 For example, the micropipe, threading screw dislocation, threading edge dislocation, basal plane dislocation, and stacking fault in a typical bulk SiC wafer are 0−0.1, 300− 500, 2000−5000, 500−1000, and <1 cm −2 , respectively. 9 Not only does the presence of these defects leads to a low yield of high-quality SiC wafers, but the need for an ultrahigh growth temperature consumes significant energy, resulting in high production costs.…”

“…However, since the PVT method decomposes polycrystalline SiC into complex mixed gases, controlling the stable growth of SiC single crystals at the gas/solid growth interface is quite difficult . As a result, defects are consistently generated during the process of growing SiC single crystals, compromising device performance and lifespan . For example, the micropipe, threading screw dislocation, threading edge dislocation, basal plane dislocation, and stacking fault in a typical bulk SiC wafer are 0–0.1, 300–500, 2000–5000, 500–1000, and <1 cm –2 , respectively .…”

Effects of proton implantation for expansion of basal plane dislocations in SiC toward suppression of bipolar degradation: review and perspective

“…Wafers with epitaxial layers have been employed for the mass production of SiC devices and are currently commercially available. Although significant research effort has been devoted to improving wafer quality, [1][2][3][4][5][6][7] wafers currently on the market contain various types of defects. In addition, both the density and distribution of defects vary widely between wafer batches.…”

Research Progress in Liquid Phase Growth of GaN Crystals

“…They are counted among the third-generation semiconductor materials, alongside SiC, AlN, and diamond. [1][2][3][4] GaN has three crystal structures: the stable hexagonal phase with a wurtzite structure, the metastable cubic phase with a zincblende structure, and the rock salt structure that only exists under extremely highpressure conditions. [5] While there have been reports on the cubic phase of GaN crystals, [6] the vast majority of research on GaN materials and devices focuses on the hexagonal phase structure.…”