High-Gain N-Face AlGaN Solar-Blind Avalanche Photodiodes Using a Heterostructure as Separate Absorpt

• 作 者: 汤寅 蔡青 杨莲红 董可秀 陈敦军 陆海 张荣 郑有炓
• 机 构: Key Laboratory of Advanced Photonic and Electronic Materials, School of electronic Science and Engin
• 出 处: Chinese Physics Letters
• 发表日期: 2017年01期
• 关键词: AlGaN multiplication Solar breakdown nitride reflector quarter instead Absorptio

It is well known that Ⅲ-nitride semiconductors can generate the magnitude of MV/cm polarization electric field which is comparable with their ionization electric fields. To take full advantage of the polarization electric field, we design an N-face AlGaN solar-blind avalanche photodiode(APD) with an Al_(0.45)Ga_(0.55)N/Al_(0.3)Ga_(0.7)N heterostructure as separate absorption and multiplication(SAM) regions. The simulation results show that the N-face APDs are more beneficial to improving the avalanche gain and reducing the avalanche breakdown voltage compared with the Ga-face APDs due to the effect of the polarization electric field. Furthermore, the Al_(0.45)Ga_(0.55)N/Al_(0.3)Ga_(0.7)N heterostructure SAM regions used in APDs instead of homogeneous Al_(0.45)Ga_(0.55)N SAM structure can increase significantly avalanche gain because of the increased hole ionization coefficient by using the relatively low Al-content AlGaN in the multiplication region. Meanwhile, a quarter-wave AlGaN/AIN distributed Bragg reflector structure at the bottom of the device is designed to remain a solar-blind characteristic of the heterostructure SAM-APDs.

It is well known that Ⅲ-nitride semiconductors can generate the magnitude of MV / cm polarization electric field which is comparable with their ionization electric fields. To take full advantage of the polarization electric field, we design an N-face AlGaN solar-blind avalanche The simulation results show that the N-face APDs are more beneficial to (AP) with an Al 0.45 Ga 0.55 N / Al 0.3 Ga 0.7 N heterostructure as separate absorption and multiplication (SAM) regions. improving the avalanche gain and reducing the Avalanche breakdown voltage compared with the Ga-face APDs due to the effect of the polarization electric field. Furthermore, the Al_ (0.45) Ga_ (0.55) N / Al_ (0.3) Ga_ (0.7) N heterostructure SAM regions used in APDs instead of homogeneous Al_ (0.45) Ga_ (0.55) N SAM structure can increase significantly avalanche gain because of the increased hole ionization coefficient by using the relatively low Al-content AlGaN in the multiplication region. Meanwhile, a quarter- wave AlGaN / A IN distributed Bragg reflector structure at the bottom of the device is designed to remain a solar-blind characteristic of the heterostructure SAM-APDs.