Monolithic n-i-p-i-n type wide-spectrum photodetector

Abstract

The invention provides a monolithic n-i-p-i-n type wide-spectrum photodetector including an InP substrate; an InP of a first conductivity type as a lower contact layer on the InP substrate is formed;an intrinsic Inx1Ga1-x1As as the first absorption layer is formed over the lower contact layer; a second conductive type InP as a common contact layer is formed over the first absorbing layer; a lattice adapted buffer lay is formed over common contact layer; Inx2Ga1-2As of intrinsic or first conductivity class is formed over the lattice adaptation buffer layer; a first conductivity type Inx3Al1-x3As upper contact layer is formed on a second absorption layer. A PIN detector with standard wavelength response and a PIN detector with extended wavelength response are combined by adopting a two-color detector design scheme, and PD1 is used to respond to a spectrum range below 1.7 mum, PD2 is used to respond to a spectrum range of 1.7 mum-2.5 mum. PD1 and PD2 share a P electrode to form a back incident n-i-p-i-n type device structure, and the modulation of the response spectrum by switching the electrode bias is realized.

Description

technical field [0001] The invention belongs to the technical field of semiconductor design and manufacture, relates to the technical field of InP-based III-V compound semiconductor optoelectronic devices, and specifically relates to a single-chip n-i-p-i-n type wide-spectrum photodetector with a novel structure. Background technique [0002] The "near-infrared-short-wave infrared" (0.75-2.5μm) spectrum band is the most important band range for spectral sensing detection and spectral analysis applications, and has application requirements in the fields of industry, communication, medical treatment, food, biochemistry, agriculture, and public safety. widely. At present, in this spectral range, InGaAs and HgCdTe are the most mainstream detector technologies. [0003] In recent years, with the continuous progress of material preparation technology, emerging detector technologies such as type-II superlattice (T2SL) and colloidal quantum dots (CQD) have also developed rapidly. ...

AI Technical Summary

Problems solved by technology

For the extended short-wave infrared InGaAs detector with a response cutoff wavelength greater than 1.7 μm, due to the absorption of the narrow bandgap lattice mismatch buffer layer or the contact top layer (back-incidence or front-illumination), the quantum efficiency in the short-wavelength direction decreases significantly, affecting To improve the detection sensitivity and spectral response range; when the response cut-off wavelength extends to 2.5 μm, the response turn-on wavelength is greater than 1.2 μm, and the quantum efficiency below 1.5 μm wavelength is usually lower than 30%, how to improve the detection sensitivity of InGaAs detectors below 1.7 μm wavelength It is a technical problem that needs to be solved urgently

Images