Silicon Radiation Detectors - Materials and Applications

Abstract

Silicon nuclear radiation detectors are available today in a large variety of sizes and types. This profusion has been made possible by the ever increasing quality and diameter silicon single crystals, new processing technologies and techniques, and innovative detector design. The salient characteristics of the four basic detector groups, diffused junction, ion implanted, surface barrier, and lithium drift are reviewed along with the silicon crystal requirements. Results of crystal imperfections detected by 1 ithium ion compensation are presented. Processing technologies and techniques are described. Two recent novel position-sensitive detector designs are discussed--one in high~energy particle track reconstruction and the other in x-ray angiography. The unique experimental results obtained with these devices are presented.

Hydrogen in crystalline semiconductors

“…Calculations by Estreicher (27) show the stable position for H+ to be BC while Li+ and Cu+ occupy an antibonding (AB) site (Fig: 2). This work was stimulated not only by the hydrogen related findings but al~o in part by the well established passivation of acceptors by Li (14); an effect which had been used extensively for many years in the fabrication of large volume lithium drifted germanium gamma ray detectors (28) and lithium drifted SiX-ray and particle detectors, (29) and by the very recent observation that boron and other shallow acceptors are ,passivated in Si by polishing wafers (30). The theoretical findings together with perturbed angular correlation (PAC) position decay experiments (31) and additional experimental evidence (32) show that polishing related passivation is not hydrogen related but most likely due to rapidly diffusing interstitial copper.…”

“…Calculations by Estreicher [27] show the stable position for H t to he BC while Li' and Cu+ occupy an antibonding (AB) site (figure 2). This work was stimulated not only by the hydrogen-related findings but also in part by the well established passivation of acceptors by Li [14]; a n effect which had been used extensively for many years in the fabrication of large-volume lithiumdrifted germanium gamma-ray detectors [28] and lithium-drifted Si x-ray and particle detectors [29], and by the very recent observation that boron and other shallow acceptors are passivated in Si by polishing wafers DO].…”