Study of Chemical Etching and Chemo-Mechanical Polishing on CdZnTe Nuclear Detectors

作     者：Aaron L. Adams Stephen U. Egarievwe Ezekiel O. Agbalagba Rubi Gul Anwar Hossain Utpal N. Roy Ralph B. James 

作者机构：Department of Mechanical & Civil Engineering and Construction Management Alabama A&M University Huntsville AL USA Nuclear Engineering and Radiological Science Center Alabama A&M University Huntsville AL USA Department of Nonproliferation and National Security Brookhaven National Laboratory Upton NY USA Department of Electrical Engineering and Computer Science Alabama A&M University Huntsville AL USA Department of Physics Federal University of Petroleum Resources Effurun Nigeria Science and Technology Savannah River National Laboratory Aiken SC USA 

出 版 物：《Journal of Materials Science and Chemical Engineering》 (材料科学与化学工程（英文）)

年 卷 期：2019年第7卷第8期

页      面：33-41页

学科分类：080903[工学-微电子学与固体电子学] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

主　　题：CdZnTe Chemical Etching Chemo-Mechanical Polishing Gamma Rays Nuclear Detectors X-Ray Photoelectron Spectroscopy 

摘      要：Cadmium zinc telluride (CdZnTe) semiconductor has applications in the detection of X-rays and gamma-rays at room temperature without having to use a cooling system. Chemical etching and chemo-mechanical polishing are processes used to smoothen CdZnTe wafer during detector device fabrication. These processes reduce surface damages left after polishing the wafers. In this paper, we compare the effects of etching and chemo-mechanical polishing on CdZnTe nuclear detectors, using a solution of hydrogen bromide in hydrogen peroxide and ethylene glycol mixture. X-ray photoelectron spectroscopy (XPS) was used to monitor TeO2 on the wafer surfaces. Current-voltage and detector-response measurements were made to study the electrical properties and energy resolution. XPS results showed that the chemical etching process resulted in the formation of more TeO2 on the detector surfaces compared to chemo-mechanical polishing. The electrical resistivity of the detector is of the order of 1010 Ω-cm. The chemo-mechanical polishing process increased the leakage current more that chemical etching. For freshly treated surfaces, the etching process is more detrimental to the energy resolution compared to chemo-mechanically polishing.