Gaas Nuclear Radiation Detector Development

Gallium arsenide(GaAs) has been studied as a semiconductor material for more than 40 years. It was the first compound semiconductor which demonstrated high energy resolution forγ-rays at room temperature. Nowadays, with the improvement of the Liquid Encapsulated Czochralski (LEC) material quality , detector performance is improved rapidly.In the present work , radiation detectors basted on SI-LEC GaAs have been investigated by using two different structures(i)a PIN detector with a P⁺N junction which is formed by an alloyed Zn/Au metallization (ii)a Au surface barrier detector. The pulse height spectra are obtained with ¹²⁵I,²⁴¹Am and ⁵⁷Co sources and corresponding detector energy resolution is evaluated. In order to make the spectrometric performance better, we increase the thickness of the semiconductor wafer to improve detect efficiency and increase area to improve sensitivity, which is the experiment investigation focuses on.Generally, the results of testing detectors with different structures indicate that we have a sophisticated detector processing technology. The energy resolution obtained for detection of 59.5keVγ-photons is 6.4keV and 27.5keV X-rays is 4.02keV,respectively at room temperature. The results are in agreement with previous international published results. Now detectors with the above characteristics are suitable for application, which have an important function in promoting semiconductor detector progress.