MANUFACTURE OF ARRAY TYPE CDHGTE INFRARED DETECTOR

摘要

PURPOSE:To prevent the dispersion of the diameter of a P-N junction, and to equalize picture elements in sensibility by vapor-phase epitaxial growing second conductivity type CdHgTe on a first conductivity type CdHgTe layer with holes arranged in an array shape. CONSTITUTION:P-type Cd0.2Hg0.8Te 2 is grown on the face (111) B of a Cd0.97 Zn0.03Te substrate 1 in thickness of 15mum through a liquid phase epitaxial method. A negative resist is used for the wafer, and holes having a diameter of 30mum and depth of 5mum are bored at a pitch of 50mum by the use of an etchant of 2% Br-methanol. N-type Cd0.2Hg0.8Te 3 is grown on the holes with a thickness of 10mum through a molecular beam epitaxial method. When N-type Cd0.3Hg0.8Te 3 is polished in approximately 2mum until the holes of the N-type CdHgTe are not viewed and etching is conducted in approximately 9mum by the use of the etchant of 2% Br-methanol, sections except N-type CdHgTe in the holes of P-type CdHgTe are removed because 11mum in total is taken off. A ZnS film for protecting the surface of a P-N junction is shaped 0.5mum in thickness on the N-type CdHgTe, and an electrode of Cr:500Angstrom and Au:2000Angstrom is formed through a lift-off method.