崖层对单行载流子光电探测器的影响研究  

Study of the Influence of Cliff Layer on Uni-Traveling-Carrier Photodetector

作　　者：陈代尧[1] 余学才[1] 汪平河[1] 刘永[1] 

机构地区：[1]电子科技大学光电信息学院,四川成都610054

出　　处：《中国激光》2014年第3期260-265,共6页Chinese Journal of Lasers

基　　金：国家自然科学基金(61177036;60925019)

摘　　要：分析了崖层在单行载流子光电探测器(UTC-PD)中的作用,以及其对UTC-PD的3dB带宽的影响。研究结果表明,崖层使得异质结处电场强度增加,且电场向吸收区延伸,使电子在吸收区的渡越时间和积累程度降低,从而导致3dB带宽和饱和电流增加;崖层的掺杂浓度和厚度都会对3dB带宽产生显著的影响;当崖层厚度与掺杂浓度的乘积一定,且收集区保持耗尽时,随着崖层厚度的增加(掺杂浓度减小),3dB带宽下降,但是,只要崖层的厚度不是太厚(通常为十几纳米到几十纳米),则无论是改变崖层厚度,还是改变掺杂浓度,3dB带宽的下降都可以忽略不计,即3dB带宽基本相等。Deeper researches on the impacts of a cliff layer on uni-traveling-carrier photodetector （UTC-PD） are presented, especially the influence on 3 dB bandwidth. The results show that a cliff layer enhances the intensity of the electric field which extends to the absorption region in the heterojunction, makes the electron transit time and electron accumulation level reduce in the absorber, and eventually leads to the increase in 3 dB bandwidth and saturation current. The results also reveal that, both the doping concentration and thickness of cliff layer have a significant impact on 3 dB bandwidth. For a thicker cliff layer, as the product of the thickness and doping concentration is unchanged and the collection region remains depleted, the 3 dB bandwidth drops with the increase of cliff layer thickness. However, for a thinner cliff layer, typically ten to several tens of nanometers, whether the cliff layer thickness or the doping concentration is alternated, the decreases of 3 dB bandwidth can be ignored, that is, the 3 dB bandwidth is almost invariant.

关 键 词：探测器 崖层 单行载流子 3 dB带宽 

分 类 号：TN364.2[电子电信—物理电子学]