High responsivity graphene-InGaAs near-infrared photodetector realized by hole trapping and its response saturation mechanism

Abstract

Graphene is an ideal material for wide spectrum detector owing to its special band structure, but its low light absorption and fast composite of photogenerated carriers lead to a weak response performance. In this paper, we designed a unique photoconductive graphene-InGaAs photodetector. The built-in electric field was formed between graphene and InGaAs, which can prolong the lifetime of photogenerated carriers and improve the response of devices by confining the holes. Compared with graphene-Si structure, a higher built-in electric field and reach to 0.54 eV is formed. It enables the device to achieve a responsivity of 60 AW−1 and a photoconductive gain of 79.4 at 792 nm. In the 1550 nm communication band, the responsivity of the device is also greater than 10 AW−1 and response speed is less than 2 ms. Meanwhile, the saturation phenomenon of light response was also found in this photoconductive graphene heterojunction detector during the experiment, we have explained the phenomenon by the capacitance theory of the built-in electric field, and the maximum optical responsivity of the detector is calculated theoretically, which is in good agreement with the measurement result.

Ultra‐Sensitive and Low‐Power‐Consumption Organic Phototransistor Enables Nighttime Illumination Perception for Bionic Mesopic Vision

“…The R values of 0.56-12.53 A W −1 in the visible and NIR spec-tral ranges are comparable to those of state-of-the-art Si photodiodes (0.3-0.58 A W −1 ) [43] and InGaAs NIR phototransistors (>10 A W −1 ). [44] Such a large R value corroborates that the LPE-OPT has an extraordinarily enhanced light sensitivity. As a key performance metric to assess the ability to perceive weak signals, noise equivalent power (NEP) is the minimum optical signal power required for an output signal-to-noise ratio of one.…”

A broadband 3D microtubular photodetector based on a single wall carbon nanotube–graphene heterojunction

“…Under illumination at 940 nm with a power of 0.3 nW, a value of R ph as high as 1.9 × 10 4 A W −1 is obtained, which is two orders of magnitude higher than that of a typical planar SWCNT/graphene photodetector (∼100 A W −1 ) 20 and three orders of magnitude higher than that of a representative graphene-InGaAs photodetector (60 A W −1 ) within the NIR region. 41 The transient photoresponse curve can be found in Fig. S6 †.…”

Integrating 2D layered materials with 3D bulk materials as van der Waals heterostructures for photodetections: Current status and perspectives

“…The photodetectors operating in near‐infrared (NIR) light range play an indispensable role in military and civil fields including optical telecommunication, target imaging, night version, security inspection, and environmental monitoring. Nowadays, the commercial market of NIR photodetectors is largely dominated by narrow bandgap semiconductors, such as PbS, InSb, InGaAs, and HgCdTe 152–154 . Even though the above devices have high sensitivity, it is undeniable that the manufacturing processes of these compounds are costly and time consuming, due to involving complicated facilities for material growth 152 .…”

“…Nowadays, the commercial market of NIR photodetectors is largely dominated by narrow bandgap semiconductors, such as PbS, InSb, InGaAs, and HgCdTe. [152][153][154] Even though the above devices have high sensitivity, it is undeniable that the manufacturing processes of these compounds are costly and time consuming, due to involving complicated facilities for material growth. 152 TMDC with narrow bandgap may provide a possible way for low-cost high efficiency NIR photodetectors.…”