Radiation detectors and methods of fabricating radiation detectors

A method for fabricating a radiation detector, the method comprising:

• mechanically polishing at least a first surface of a semiconductor wafer using a polishing sequence including a plurality of polishing steps to form a polished first surface, wherein a last polishing step of the polishing sequence includes polishing with a slurry having a grain size smaller than about 0.1 μm to create the polished first surface;
• growing a passivation oxide layer on a top of the polished first surface to seal and passivate the polished first surface;
• depositing patterned metal contacts on a top of the passivation oxide layer having at least one pattern being (i) a pattern of pixelated anode electrodes or (ii) a pattern of pixelated anode electrodes with grid electrodes having lines of electrodes aligned along centers of gaps between the pixelated anode electrodes;
• applying a protecting layer on a top of the patterned metal contacts to protect a first surface of the patterned metal contacts;
• etching a second surface of the semiconductor wafer to form an etched second surface;
• applying a monolithic cathode electrode on the etched second surface of the semiconductor wafer;
• and
• 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.