Etch pits observation and in distribution in mercury indium telluride single crystals

Mercury indium telluride (MIT) crystal, Hg_(3-3x)In _2xTe₃ (x = 0.5), is one of the most promising novel materials for room temperature near-infrared photodetectors. By the vertical Bridgman method, several MIT ingots were grown. An etchant for displaying the etch pits was developed. The etch pits of dislocations and boundary were observed. It was found that the etch pits were in the shape of the isosceles triangle, and the etch pits' density of dislocations was about 4 × 10 ⁵ cm^-2. The characteristics of In in MIT ingots were studied. The composition distributions reveal that the segregation coefficient of In in MIT is 1.15. Te and In reduced at the grain boundary, while they were homogeneous within the grains. I-V measurements show that In/MIT contact was a good Ohmic contact. The resistivity of the measured MIT wafers was about 238 Ω cm.