PIN、NBP及NBN型InAsSb中波红外探测器光电性能研究

Optical and Electrical Properties of PIN,NBN and NBP Mid-wave InAsSb Infrared Photodetectors

系统探索了GaSb(001)衬底上InAsSb体材料的分子束外延生长和PIN型、NBP型及NBN型InAsSb单元单色红外探测器的制备工艺,并对其光学、电学等相关物理特性进行了研究对比.PIN型InAsSb单元探测器的R0A为224Ω·cm2(100K),77K下峰值探测率为3.6×1010cmHz1/2/W.NBN型和NBP型InAsSb单元探测器的R0A都达到了105Ω·cm2(100K)的量级,但NBN型比NBP型的R0A值更大,暗电流密度更低,77K下峰值探测率分别为8.5×101 2cmHz1/2/W和2.4×108cmHz1/2/W.最后制备完成了50%截止波长为3.8μm(PIN型)、3.4μm(NBP型)、2.6μm(NBN型)的InAsSb单元探测器.

In this paper, we study deeply and systematically InAsSb bulk materials grown on GaSh（001） substrate by molecular beam epitaxy. We have fabricated PIN-type InAsSb mid-wave infrared photodetector and infrared photodetectors containing InAsSb absorber regions and A1AsSb barriers in n-barrier-n（NBN） and n-barrier-p（NBP） configurations, and characterized them by current-voltage and photocurrent. The dynamic resistance of the PIN-type InAsSb photodetec- tor is 224 Ω cm2（100 K）,the peak detectivity is 3. 6×1010 cm Hz1/2/W（77 K）. At 100 K,the dynamic resistance of the NBP and the NBN near zero bias are approximately an order of 105 magnitude, but the dynamic resistance of the NBP less than the dynamic resistance of the nBn biased for high responsivity,indicating that the reduction in shot noise achieved by operating the NBP near zero bias may be offset by an increase in Johnson noise. At 77 K,the peak detectivity of the NBP and the NBN separately is 8. 5×1012 cmHz1/2/W and 2. 4X108 cmHz1/2/W. Finally,the 50% cut-off wavelength of 3.8 μm（PIN-type）,3.4 μm（NBP-type）,2.6μm（NBN-type） InAsSb de- tectors have been achieved.