Addressing gain-bandwidth trade-off by a monolithically integrated photovoltaic transistor

Abstract

The gain-bandwidth trade-off limits the development of high-performance photodetectors; i.e., the mutual restraint between the response speed and gain has intrinsically limited performance optimization of photomultiplication phototransistors and photodiodes. Here, we show that a monolithically integrated photovoltaic transistor can solve this dilemma. In this structure, the photovoltage generated by the superimposed perovskite solar cell, acting as a float gate, is amplified by the underlying metal oxide field-effect transistor. By eliminating deep-trap defects through processing optimization, we achieved devices with a maximum responsivity close to 6 × 10 4 A/W, a specific detectivity ( D *) of 1.06 × 10 13 Jones, and an f 3dB of 1.2 MHz at a low driving voltage of 3 V. As a result, a record gain-bandwidth product is achieved. The device further exhibits the advantage in photoplethysmography detection with weak illuminations, where our device accurately detects the detailed features that are out of the capability of conventional photodetectors.

The UV–vis‐NIR Broadband Ultrafast Flexible Sn‐Pb Perovskite Photodetector for Multispectral Imaging to Distinguish Substance and Foreign‐Body in Biological Tissues

“…Furthermore, the dark current fluctuation remains 108.7% within 400 s. The noise power spectrum shows that the noise of the Sn‐Pb perovskite photodetector is mainly dominated by 1/f noise, as shown in Figure 2b. [ 32–34 ] The noise density ( i n ) of the device is close to 3.1 × 10 −11 AHz 1/2 at 1 Hz. Responsivity and detectivity are two key parameters of the photodetector.…”

“…Furthermore, the dark current fluctuation remains 108.7% within 400 s. The noise power spectrum shows that the noise of the Sn-Pb perovskite photodetector is mainly dominated by 1/f noise, as shown in Figure 2b. [32][33][34] The noise…”

Perovskite/GaN-Based Light-Modulated Bipolar Junction Transistor for High Comprehensive Performance Visible-Blind Ultraviolet Photodetection

“…Therefore, no matter whether the photocarriers are generated in GaN or MAPbCl 3 films, the photoresponse of our light-modulated BJT is dominated by the enhanced junction with efficient charge separation and transfer, showing a saturated photocurrent like a photodiode operated at reverse bias. In addition, with the large distance between the lateral electrodes, the large trap states in the GaN layer can temporally capture the photogenerated electrons during charge transport, , which results in the multiplication of photocurrent with photoconductive gain.…”

Retinomorphic Motion Detector Fabricated with Organic Infrared Semiconductors

“…For R greater than tens of kΩ, the device has reached the point of diminishing return for voltage gain, and large R values would also delay the RC time constant and gain‐bandwidth product. [ 35 ] Hence, in the following characterization, the retinomorphic sensor was set with a 10 kΩ resistor to attain sufficient voltage gain and retain fast response speed.…”