Ultrahigh Photogain Short-Wave Infrared Detectors Enabled by Integrating Graphene and Hyperdoped Silicon

Abstract

Highly sensitive short-wave infrared (SWIR) detectors, compatible with the silicon-based complementary metal oxide semiconductor (CMOS) process, are regarded as the key enabling components in the miniaturized system for weak signal detection. To date, the high photogain devices are greatly limited by a large bias voltage, low-temperature refrigeration, narrow response band, and complex fabrication processes. Here, we demonstrate high photogain detectors working in the SWIR region at room temperature, which use graphene for charge transport and Te-hyperdoped silicon (Te−Si) for infrared absorption. The prolonged lifetime of carriers, combined with the built-in potential generated at the interface between the graphene and the Te−Si, leads to an ultrahigh photogain of 10 9 at room temperature (300 K) for 1.55 μm light. The gain can be improved to 10 12 , accompanied by a noise equivalent power (NEP) of 0.08 pW Hz −1/2 at 80 K. Moreover, the proposed device exhibits a NEP of 4.36 pW Hz −1/2 at 300 K at the wavelength of 2.7 μm, which is exceeding the working region of InGaAs detectors. This research shows that graphene can be used as an efficient platform for silicon-based SWIR detection and provides a strategy for the low-power, uncooled, high-gain infrared detectors compatible with the CMOS process.

Role of Defects in the Transport Properties and Photoresponse of a Silicon–MoS2 Mixed-Dimensional Van der Waals Heterostructure

“…The relatively fast response time can be attributed to the rapid separation of the photogenerated carriers by the built-in electric field at the Si–MoS 2 junction. Both the rise and fall times increase with temperature, in contrast to what is observed in the graphene–silicon detector . The rise time and decay time (Figure c,d) increase from 19.7 to 36 μs and from 57 to 116 μs, respectively, as the temperature increases from 100 to 300 K. This increase can be associated with the generation of more shallow levels with temperature.…”

“…Both the rise and fall times increase with temperature, in contrast to what is observed in the graphene−silicon detector. 47 The rise time and decay time (Figure 4c,d) increase from 19.7 to 36 μs and from 57 to 116 μs, respectively, as the temperature increases from 100 to 300 K. This increase can be associated with the generation of more shallow levels with temperature. The energy difference between the steady-state Fermi level (explained detailed in next section) and their respective band edges depends on the absolute temperature.…”

Development of Broadband PbS Quantum Dot/Graphene Photodetector Arrays with High-Speed Readout Circuits for Flexible Imagers

“…All curves show monotonically increasing R* values with decreasing light power, which is consistent with the literature due to the more efficient light detection at low power with reduced nonradiative recombination. [6,14] With decreasing wavelengths, the R* value increases monotonically, which is ascribed to the higher kinetic energy of photo-excited charge carriers (and hence lower charge recombination) by shorterwavelength photons. Nevertheless, high R* values have been observed in the entire UV−vis−NIR spectrum, as shown in Figure 3c.…”

“…13 Recent advances in detectors incorporating graphene without QDs, such as Te-hyperdoped silicon, have shown an impressive D* of 10 9 Jones at a wavelength of 1.55 μm. 14 grating has been recently shown to greatly enhance the photogating in monolayer graphene, achieving a very high D* of 10 12 Jones at a wavelength of 1.55 μm. 15 Developing photodetectors into an array is critical to practical applications for imaging.…”

“…Graphene-based devices incorporating nanorods of PbS have been recently demonstrated to have a high D * of 10 9 Jones at a wavelength of 2.7 μW . Recent advances in detectors incorporating graphene without QDs, such as Te-hyperdoped silicon, have shown an impressive D * of 10 9 Jones at a wavelength of 1.55 μm . Use of a silicon grating has been recently shown to greatly enhance the photogating in monolayer graphene, achieving a very high D * of 10 12 Jones at a wavelength of 1.55 μm …”