Keywords: 
• 碲镉汞(MCT) /
• B掺杂 /
• 第一性原理 /
• 形成能

Abstract: Using the first-principles method based on the density functional theory,we study the doping effect of B impurity in HgCdTe （MCT）.We find that the most stable configuration of the impurity is at the B hexagonal interstitial position,rather than at the in-situ substitution.The electronic structures and the density of states of B hexagonal interstitial doped MCT are systematically investigated. Near neighbour（NN） and next-near-neighbor（NNN） atoms around the B impurity are obviously relaxed.The relaxation induces the breaking of NN Te-Hg covalent bond.Moreover,B hexagonal interstitial behaves as triple n-type dopant.The charged state analysis indicates that B_i~h（2Hg1Cd） with three positive charges is most stable and forms an effecient donor.However,as long as the Hg vacancy exists,complex impurity between Hg vacancy and B impurity can be easily formed,its binding energy reaches up to 0.96 eV.Such complex behaves as single n-type dopant.Considering radiation damage of B ion implantation,the complex is a main factor restricting the activation of B ion in MCT.