Photopeak detection by an InSb radiation detector made of liquid phase epitaxially grown crystals

We have fabricated a radiation detector using a p-type InSb crystal grown by liquid phase epitaxy (LPE). At temperatures below 100 K, the resistivity of the LPE crystal was over an order of magnitude higher than that of the commercial InSb crystal substrate. The resistance of the InSb detector is 680 kΩ at 4.2 K, which is one order of magnitude higher than that of detectors fabricated from commercial InSb wafers and, in an improvement over previous results, the energy resolution of 241Am alpha particles reaches 3%. In addition, we also observe the photopeak of gamma-rays emitted by 133Ba.