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

Area of Science:

• Materials Science
• Optoelectronics
• Semiconductor Physics

Background:

• Short-wave infrared (SWIR) detectors are crucial for weak signal detection in miniaturized systems.
• Existing high photogain SWIR detectors face limitations like high bias voltage, low-temperature needs, narrow bands, and complex fabrication.
• Silicon-based complementary metal oxide semiconductor (CMOS) compatibility is essential for integrated systems.

Purpose of the Study:

• To demonstrate high photogain SWIR detectors operating at room temperature.
• To overcome the limitations of current SWIR detector technologies.
• To develop a silicon-compatible, low-power, uncooled, high-gain infrared detector.

Main Methods:

• Utilized graphene for efficient charge transport.
• Employed Te-hyperdoped silicon (Te-Si) for infrared absorption.
• Investigated carrier lifetime and built-in potential at the graphene-Te-Si interface.

Main Results:

• Achieved ultrahigh photogain of 10^9 at room temperature (300 K) for 1.55 μm light.
• Enhanced gain to 10^12 with a noise equivalent power (NEP) of 0.08 pW Hz^-1/2 at 80 K.
• Demonstrated NEP of 4.36 pW Hz^-1/2 at 300 K for 2.7 μm, surpassing InGaAs detector ranges.

Conclusions:

• Graphene serves as an effective platform for silicon-based SWIR detection.
• The developed device offers a strategy for low-power, uncooled, high-gain infrared detectors.
• This technology is compatible with CMOS processes, enabling widespread application.