Semiconductor gamma ray detector including compositionally graded, leakage current blocking potential barrier layers and method of fabricating the detector

摘要: A P-type/intrinsic/N-type (P-I-N) gamma ray detector (10) includes a semiconductor layer (12) of intrinsic cadmium telluride (CdTe) or zinc (CdZnTe). P- and N-doped layers (14,16) mercury (HgCdTe) are formed on the opposite surfaces (12a,12b) (12), ohmic metal contacts (18,20) doped (14,16). The composition is Hg1-x Cdx Te, graded such that x progressively decreases with distance from toward (18,20). This causes bandgap to also decrease (18,20), forming potential barriers (E1,E2) which block leakage currents constituted by injection minority carriers into provide low resistance between annealed during fabrication, causing diffusion (14,16), thereby increasing heights (E1,E2).