Technology Commercialization and Partnerships | BSA 12-25: Optically Engineered Radiation Detector

Category: electronics & instrumentation

BSA 12-25: Optically Engineered Radiation Detector

BNL Reference Number: BSA 12-25

Patent Status: U.S. Patent Number 6,373,064 was issued on April 16, 2002

Summary

This invention comprises a semiconductor radiation detector, specifically an improved, field engineered semiconductor radiation spectrometer, based on engineering of the internal electrical field distribution via illumination by an optical light beam with a selected photon energy. This invention involves engineering the internal electrical field through an external infrared light source. A planar semiconductor radiation detector is applied with a bias voltage, and an optical light beam with a selected photon energy is used to illuminate the detector and engineer the internal electric field. Different light beam intensities or photon energies produce different distributions of the internal electric field. The width of the electric field can be fine-tuned by changing the optical beam intensity and wavelength, so that the radiation detector performance can be optimized. The detector is portable, small in size, and operates at room temperature.

Description

The invention involves a field engineered radiation spectrometer (FERADS). According to the present invention, improved semiconductor radiation detectors are obtained by a method involving engineering the internal electrical field through an external light source, where the photon energy of the light source is near the semiconductor band gap. By applying a bias voltage across a planar semiconductor radiation detector and illuminating the detector with an optical light beam with a selected photon energy, the internal electric field can be engineered. Tests have shown that different light beam intensities or photon energies produce different distributions of the internal electric field. By the method of this invention, the width of the electric field can be fine-tuned by changing the optical beam intensity and wavelength, so that the radiation detector performance can be optimized. The external light source may be infrared. The planar detector may be composed of a single pixellated, or strip electrode. Different light beam intensities or photon energies produce different distributions of the internal electric field. The width of the electric field can be fine-tuned by changing the optical beam intensity and wavelength, so that the radiation detector performance can be optimized.

Benefits

Compared with the prior known complex, destructive and expensive hardware modifications used to engineer the electric field distribution, the optical method of this invention provides a simple, nondestructive, contactless, and less costly approach to produce improved semiconductor radiation detectors. The improved semiconductor radiation detector is portable, small size, and operates at room temperature. This invention enables stacking of many smaller detectors, vertically and horizontally, to further increase the overall detector efficiency.

Applications and Industries

Semiconductor radiation detectors are now used in a large variety of fields, including nuclear physics, X-ray and gamma ray astronomy, and nuclear medicine. Their imaging capabilities, good energy resolution, and the ability to fabricate compact systems are very attractive features, in comparison with other types of detectors, such as gas detectors and scintillators. Medical, imaging, nuclear nonproliferation, non-destructive detection, radiation imaging, and homeland security applications.