Processing of microstrip detectors on Czochralski grown high resistivity silicon substrates

We have processed large-area strip sensors on silicon wafers grown by the magnetic Czochralski (MCZ) method. The n-type MCZ silicon wafers manufactured by Okmetic Oyj have nominal resistivity of 900 Omega cm and oxygen concentration of less than 10 ppma. The Photoconductive Decay (PCD) measurements, current voltage measurements and capacitance-voltage measurements were made to characterise the samples. The leakage current of 3 muA at 900 V bias voltage was measured on the 32.5 cm(2) detector. Detector depletion took place at about 420 V. According to PCD measurements, process induced contamination was effectively bound and neutralised by the oxygen present in Czochralski silicon. During the sample processing, the silicon resistivity increased in spite of the lack of specific donor-killing heat treatment. (C) 2003 Elsevier B.V. All rights reserved.