【摘要】 使用二维器件模拟软件Medici,对SiC_1-x Ge_x/SiC异质结的光电特性进行了模拟.设计了N型重掺杂SiC层的厚度为 1μm,P型轻掺杂SiC_1-x Ge_x/SiC层厚为 0. 4μm,二者之间形成突变异质结.在反向偏压 3V、光强度为 0. 23W /cm2的条件下,p-n+SiC0. 8Ge0. 2 /SiC和p-n+SiC0. 7Ge0. 3 /SiC敏感波长λ分别可以达到0. 64μm和 0. 7μm,光电流分别为 7. 765×10-7 A/μm和 7. 438×10-7 A/μm;为了进一步提高SiC1-xGex/SiC异质结的光电流,我们把p-n+两层结构改进为p i n三层结构.在同样的偏压、光照条件下,p i nSiC0. 8Ge0. 2 /SiC和p i nSiC0. 7Ge0. 3 /SiC的光电流分别达到 1. 6734×10-6 A/μm和 1. 844×10-6 A/μm.更多还原

【Abstract】 Photoelectric characteristics of SiC 1 x Ge x/SiC heterojunction diode were simulated using MEDICI tools, and the simulation results are presented and discussed in this letter. The abrupt heterojunction diode is composed of a 1 μm thick heavily doped n type SiC layer and a 0.4 μm thick lightly doped p type SiC 1 x Ge x layer with varied composition ratios. It has been shown that photocurrent of thep -n + SiC 1 x Ge x/SiCdiodeisnotdecreasedapparentlybychangethecompositionratiofrom0.2to 0.3 for the applied reverse bias voltage of 3 V and the incident light intensity of 0.23 W/cm 2. Corresponding photocurrents of the diodes are 7.765×10 -7 A/μm and 7.438×10 -7 A/ μm, and the longest wavelength limits are 0.64 μm and 0.70 μm, respectively. It has also been shown by the simulation results that p i n structure composed by adding a p + SiC 1 x Ge x thin layer on top of the lightly doped p type SiC 1 x Ge x layer is much better for obtaining a higher photocurrent. Under the same conditions, photocurrents of 1.6734×10 -6 A/μm and 1.844×10 -6 A/μm can be obtained in the p i n SiC 1 x Ge x/SiC diodes with x = 0.2 and 0.3, respectively.更多还原