Patent ID: 7518207

Claim:
A multilayer structure for use in a device for detection of microwave, millimeter, infrared (IR), ultraviolet, X-ray or gamma radiation comprising: a silicon based substrate; and an epitaxial Cd 1-z Zn z X x X′ 1-x film grown on the silicon based substrate by molecular beam epitaxy from multiple material sources where the flux of each of the multiple material sources is controlled under a given set of epitaxial growth conditions including temperature, where X is a chalcogenide selected from the group consisting of S and Se; X′ is a higher atomic number chalcogenide relative to X and X′ is selected from the group consisting of S, Se and Te; x is a number greater than zero and less than or equal to 0.097; and z is a number greater than or equal to 0.003 and less than or equal to 0.02, such that x+z is a value less than or equal to 0.10; a radiation sensing Hg 1-y Cd y Te layer grown on the Cd 1-z Zn z X x Z′ 1-x film, the Hg 1-y Cd y Te layer being substantially lattice matched to the Cd 1-z Zn z X x X′ 1-x film, where y is a number between 0.15 and 0.35 such that the effects of any mismatch are insignificant to device performance and the surface defect density is less than 500 per centimeter squared.