Observation of deep levels and their hole capture behavior in p-type 4H-SiC epilayers with and without electron irradiation

電子線照射または未照射p型4H-SiCエピ膜中の深い準位及びその正孔捕獲挙動の観察

加藤 正史*; 吉原 一輝*; 市村 正也*; 畑山 智亮*; 大島 武

Kato, Masashi*; Yoshihara, Kazuki*; Ichimura, Masaya*; Hatayama, Tomoaki*; Oshima, Takeshi

Deep levels in p-type hexagonal (4H) silicon carbide (SiC) epilayers irradiated with and without electrons at 160 keV and subsequent annealing at 1000 C were investigated. Current deep level transient spectroscopy (I-DLTS) was applied to investigate deep levels. As a result, Deep levels with activation energies less than 0.35 eV which are located near the valence band were detected. Also, two deep levels (AP1 and AP2) existed in all samples. Other deep levels appeared after the electron irradiation. Since electrons with an energy of 160 keV can knock-on only carbon atoms from the lattice site of SiC, it was concluded that the deep levels observed after irradiation were related to carbon vacancy V.