Capacitance Method for Eliminating Gas Ionization Noise in X-ray Detection Performance Testing

The exploration of semiconductive materials for direct X-ray detection has aroused intense interest recently, and many perovskites and MOFs claimed to have excellent X-ray detection abilities. However, a recent report indicates that gas ionization introduces significant interference when evaluating the X-ray detection performance under ambient conditions by the widely used two-probe method. This work reveals that the use of a capacitance method may eliminate the gas ionization noise of semiconductor detectors by about 98% (noise signal ratio: CdTe, ∼0; CsPbBr3, ∼2%; MAPbBr3, ∼2%). This method does not require high vacuum or encapsulation and is highly suggested for the valuation of X-ray direct detection performance.