Raytheon Company

Hughes Aircraft Company

Le Thanh Pham

Andrew G Toth

Jerry R Cripe

Robert Baron

John P Sheppard

William R Peterson

An infrared detector has a multi-layer structure to simultaneously detect IR energy in different spectral bands without changing polarity of a bias imposed across the detector. Two absorption layers are separated by a barrier layer that imposes an electrical potential barrier to one of the absorption layers. Under low bias in one direction, only one layer generates a photocurrent. Under a higher bias in the same direction, both layers generate a photocurrent. Additional absorption layers may be added to detect additional bands of energy, where the additional absorption layers generate photocurrent under a bias in another direction. Two, three, and four band detection is disclosed. Where absorbing layers within a single unit cell absorb under different bias direction, the barrier layer between those different bias direction layers suppresses a diffusing electron current. A method for detecting and resolving energy absorbed in two, three, and four different energy bands is also provided.

Method and apparatus providing single bump, multi-color pixel architecture

Disclosed is a method for producing an array () of p-intrinsic-n light detectors, as is an array produced in accordance with the method. The method includes providing a wafer (); forming a first layer () having a first type of electrical conductivity (e.g., n-type) over a surface of the wafer; forming a second layer () that is an intrinsic layer on the first layer and, for each light detector, implanting or diffusing a region (A) into a surface of the second layer that is opposite the surface on the first layer, the region (A) having a second type of electrical conductivity (e.g., p-type). The method further includes forming an opening or aperture, referred to herein as a V-groove (), through the second layer at least to the first layer; and electrically contacting with a first electrical contact (B,B) the first layer through the V-groove. The method further electrically contacts each of the regions with an associated one of a second electrical contact (A), where the first and second electrical contacts are located on a same, non-radiation receiving surface of the array. In a preferred embodiment the steps of electrically contacting each comprise forming an Indium bump, and further comprise hybridizing the array with a readout integrated circuit (). In the preferred embodiment forming the first layer over the surface of the wafer includes growing a doped epitaxial layer over the surface of the wafer, or it may include implanting the first layer into the surface of the wafer. Forming the second layer on the first layer includes growing an intrinsic epitaxial layer on the first layer to a thickness of, for example 10 microns. The wafer is thinned, either mechanically, or chemically, or by both processes.

Radiation hardened visible P-I-N detector

The photo-sensitive detector region of conventional Impurity Band Conduction (IBC) detector (also known as a Blocked Impurity Band [BIB] detector) is divided into a wide detection (or collection) region and a narrow gain region by means of tailoring the doping profile. The narrow gain region is that portion of the photo-sensitive detector region closest to the blocking layer, where the electric field is the largest, whose As concentration is made smaller (in the range of 2 to 5.times.10.sup.17 cm.sup.-3) to increase the impact ionization coefficient by decreasing the electron scattering. The wide detection region is that portion of the photo-sensitive detector region furthest from the blocking layer, where the electric field is smallest and the As concentration is larger (in the range of 5 to 8.times.10.sup.17 cm.sup.-3) to decrease the impact ionization coefficient by increasing the electron scattering.

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Ventura, CA, United States of America

Le Thanh Pham