Test of CZT detectors with different pixel pitches and thicknesses

The modified horizontal Bridgman (MHB) process produces cadmium zinc telluride (CZT) crystals with high yield and excellent homogeneity. Various groups, including our own, previously reported on the test of 2times2times0.5 cm
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MHB CZT detectors grown by the company Orbotech and read out with 8times8 pixels. In this contribution, we describe the optimization of the photolithographic process used for contacting the CZT detector with pixel contacts. The optimized process gives a high yield of good pixels down to pixel diameters/pitches of 50 microns. Furthermore, we discuss the performance of 0.5 cm and 0.75 cm thick detectors contacted with 64 and 225 pixel read out with the RENA-3 ASICs from the company NOVA R&D.