摘要
Ni/β-Ga_2 O_3 lateral Schottky barrier diodes(SBDs) were fabricated on a Sn-doped quasi-degenerate n^+-Ga_2 O_3(201)bulk substrate. The resultant diodes with an area of 7.85 ×10^(-5) cm^2 exhibited excellent rectifying characteristics with an ideality factor of 1.21, a forward current density(J) of 127.4 A/cm2 at 1.4 V, a specific on-state resistance(R_(on,sp)) of1.54 mΩ·cm^2,and an ultra-high on/off ratio of 2.1 ×10^(11) at±1 V. Due to a small depletion region in the highly-doped substrate, a breakdown feature was observed at-23 V, which corresponded to a breakdown field of 2.1 MV/cm and a power figure-of-merit(VB2/R_(on)) of 3.4×10~5 W/cm^2. Forward current-voltage characteristics were described well by the thermionic emission theory while thermionic field emission and trap-assisted tunneling were the dominant transport mechanisms at low and high reverse biases, respectively, which was a result of the contribution of deep-level traps at the metal-semiconductor interface. The presence of interfacial traps also caused the difference in Schottky barrier heights of 1.31 eV and 1.64 eV respectively determined by current-voltage and capacitance-voltage characteristics. With reduced trapping effect and incorporation of drift layers, the β-Ga_2 O_3 SBDs could further provide promising materials for delivering both high current output and high breakdown voltage.
Ni/β-Ga_2 O_3 lateral Schottky barrier diodes(SBDs) were fabricated on a Sn-doped quasi-degenerate n^+-Ga_2 O_3(201)bulk substrate. The resultant diodes with an area of 7.85 ×10^(-5) cm^2 exhibited excellent rectifying characteristics with an ideality factor of 1.21, a forward current density(J) of 127.4 A/cm2 at 1.4 V, a specific on-state resistance(R_(on,sp)) of1.54 mΩ·cm^2,and an ultra-high on/off ratio of 2.1 ×10^(11) at±1 V. Due to a small depletion region in the highly-doped substrate, a breakdown feature was observed at-23 V, which corresponded to a breakdown field of 2.1 MV/cm and a power figure-of-merit(VB2/R_(on)) of 3.4×10~5 W/cm^2. Forward current-voltage characteristics were described well by the thermionic emission theory while thermionic field emission and trap-assisted tunneling were the dominant transport mechanisms at low and high reverse biases, respectively, which was a result of the contribution of deep-level traps at the metal-semiconductor interface. The presence of interfacial traps also caused the difference in Schottky barrier heights of 1.31 eV and 1.64 eV respectively determined by current-voltage and capacitance-voltage characteristics. With reduced trapping effect and incorporation of drift layers, the β-Ga_2 O_3 SBDs could further provide promising materials for delivering both high current output and high breakdown voltage.
作者
Yang Xu
Xuanhu Chen
Liang Cheng
Fang-Fang Ren
Jianjun Zhou
Song Bai
Hai Lu
Shulin Gu
Rong Zhang
Youdou Zheng
Jiandong Ye
徐阳;陈选虎;程亮;任芳芳;周建军;柏松;陆海;顾书林;张荣;郑有炓;叶建东(School of Electronic Science and Engineering,Nanjing University,Nanjing 210093,China;Collaborative Innovation Center of Solid-State Lighting and Energy-Saving Electronics,Nanjing University,Nanjing 210093,China;Research Institute of Shenzhen,Nanjing University,Shenzhen 518057,China;State Key Laboratory of Wide-Bandgap Semiconductor Power Electric Devices,The 55th Research Institute of China Electronics Technology Group Corporation,Nanjing 210016,China)
基金
supported by the National Key R&D Program of China(Grant No.2017YFB0403003)
the National Natural Science Foundation of China(Grant Nos.61774081,61322403,and 91850112)
the State Key R&D Project of Jiangsu,China(Grant No.BE2018115)
Shenzhen Fundamental Research Project,China(Grant Nos.201773239 and 201888588)
State Key Laboratory of Wide-Bandgap Semiconductor Power Electric Devices,China(Grant No.2017KF001)
the Fundamental Research Funds for the Central Universities,China(Grant Nos.021014380093 and 021014380085)
