Radiation detectors and methods of fabricating radiation detectors

摘要

Radiation detectors and methods of fabricating radiation detectors are provided. One method includes mechanically polishing at least a first surface of a semiconductor wafer using a polishing sequence including a plurality of polishing steps. The method also includes growing a passivation oxide layer on a top of the polished first surface and depositing patterned metal contacts on a top of the passivation oxide layer. The method further includes applying a protecting layer on the patterned deposited metal contacts, etching a second surface of the semiconductor and applying a monolithic cathode electrode on the etched second surface of the semiconductor. The method additionally includes removing the protecting layer from the patterned metal contacts on the first surface, wherein the patterned metal contacts are formed from one of (i) reactive metals and (ii) stiff-rigid metals for producing inter-band energy-levels in the passivation oxide layer.

主权项

1. A radiation detector comprising:
a semiconductor having energy-bands; a passivation layer on a first surface of the semiconductor, wherein the first surface is formed by multiple steps of mechanical polishing without wet etching with a stoichiometric structure configured to create the passivation layer with a high-surface-resistivity; pixelated anode electrodes having a MOS structure on the passivation layer, wherein gaps between the pixelated anode electrodes separate the pixelated anode electrodes from each other, the pixelated anode electrodes producing inter-band energy-levels in the passivation layer between the pixelated anode electrodes and the first surface based on (i) a mechanical stress between the pixelated anode electrodes and the passivation layer or (ii) at least a portion of the pixelated anodes penetrating the passivation layer, wherein a surface of the gaps include the passivation layer with the high-surface resistivity; wherein the relative energy-position between the energy-bands of the semiconductor and the inter-band energy-levels of the passivation-layer is configured to adjust an electrical current between the semiconductor and the pixelated anode electrodes based on a bias applied between the pixelated anode electrodes and the semiconductor, wherein for a first bias the pixelated anode electrodes are configured to have a high conductivity and for an opposing second polarity the pixelated anode electrode are configured as blocking contacts; and a monolithic cathode of a second surface of the semiconductor opposite the first surface.