非故意掺杂4H-SiC外延材料本征缺陷的热稳定性

采用电子顺磁共振（ESR）和低温光致发光（PL）技术，研究了退火温度对低压化学气相沉积法（LPCVD）制备的非故意掺杂 4H-SiC材料中本征缺陷稳定性的影响.结果发现，当退火时间为10 min和30 min时，本征缺陷浓度均随着退火温度的升高而增大，当退火温度达到1573 K时材料中本征缺陷浓度达到最大，继续升高退火温度将使材料中本征缺陷浓度迅速降低.退火温度对材料中本征缺陷的影响主要是由于退火中本征缺陷的稳定化过程及本征缺陷之间发生强烈的相互作用引起的. 关键词： 高温退火 本征缺陷 电子顺磁共振谱 光致发光

Stability of the intrinsic defects in unintentionally doped 4H-SiC epitaxial layer

The effects of high temperature annealing on the stability of the intrinsic defects in unintentionally doped epitaxial 4H-SiC prepared by low pressure chemical vapor deposition (LPCVD) are studied by electron spin resonance (ESR) and low-temperature photoluminescence (PL). The results showed that the concentration of intrinsic defects increases with increasing annealing temperature and reaches its maximum at 1573 K, then decreases with the gradually increasing annealing temperature when annealing time is 10 min or 30 min. The annealing temperature has an important effect on the concentration of intrinsic defects in epitaxial semi-insulating 4H-SiC prepared by LPCVD, whics is attributed to the process of intrinsic defects being stabilized and the strong interaction between the intrinsic defects during annealing.