Deep Level Studies in High-Resistive Gallium Phosphide Single Crystals. (15th December 2015)

• Record Type: Journal Article
• Authors: Das, Sandip; Chaudhuri, Sandeep K.; Mandal, Krishna C.
• Is Part Of: ECS journal of solid state science and technology. Volume 5:Number 4(2016)
• Page Start: P3059
• Page End: P3063
• Publication Date: 2015-12-15
• Subjects: crystal growth -- current transient spectroscopy (CTS) -- deep level transient spectroscopy (DLTS) -- gallium phosphide -- Schottky barrier; Solid state chemistry -- Periodicals; Electronics -- Materials -- Periodicals; Electrochemistry -- Periodicals; 541.0421
• DOI: 10.1149/2.0101604jss
• Languages: English
• ISSNs: 2162-8777

Abstract

Abstract : In an attempt to explore the possibility of using wide bandgap gallium phosphide (GaP) single crystals as radiation detectors, high resistivity iron (Fe)-doped GaP single crystal was grown using a solid state diffusion (SSD) technique. The grown ingot showed a resistivity in the order of 10 8 Ω-cm with an optical bandgap of 2.27 eV measured at room temperature. Schottky barrier diodes were fabricated by sputtering nickel (Ni) contacts on GaP wafers to study the deep level defects and junction properties. An effective donor concentration, Nd = 2.6 × 10 16 cm −3 was calculated from the capacitance-voltage measurements. Deep level transient spectroscopy (DLTS) and current transient spectroscopy (CTS) were performed on the Schottky diodes to identify the electrically active defect levels in the grown high-resistive GaP crystals. DLTS measurements revealed the presence of several vacancies, impurities, and antisite defects centers with concentrations ranging from 10 14 - 10 16 cm −3 . CTS measurements identified a new defect level in GaP crystals that could not be detected by the conventional DLTS scan due to very fast capacitance transients at temperatures below 100 K.