Dark properties and transient current response of Si0.95Ge0.05 n+p devices

In this study we present the dark properties of ‘pin’ devices fabricated with Czochralski grown Si0.95Ge0.05 bulk single crystals. The growth of such material is most challenging because of the constitutional supercooling effect. The potential advantages of Si1−xGex to be used for X- and gamma-ray detection applications are overviewed. At room temperature the generation current in the devices is too high for spectroscopy applications, but enables transient current technique (TCT) measurements. The current however drops significantly with moderate cooling. The effective majority carrier concentration is shown to be ∼2×1014 cm−3, and hole mobility ∼320 cm2/V s.