PROPERTIES OF HGTE AS A CONTACT LAYER TO N-HG1-XCDXTE

Non-alloyed ohmic contacts of HgTe to n-Hg1-xCdxTe (x = 0.40-0.60) with metallizations of Ti, In and Au have been studied. In these HgTe/Hg1-xCdxTe structures, which were grown by organometallic epitaxy, the thickness of the HgTe was varied in the range from 0.1 mum to 5.0 mum. The minimum value of specific contact resistance, rho(c), of the metal /HgTe/Hg1-xCdxTe contacts was 5 x 10(-5) OMEGA cm2 This value of rho(c) was a factor of approximately 5 greater than for metal contacts to HgTe. For both metal/HgTe and metal/HgTe/Hg1-xCdxTe contacts, a thickness of the HgTe layer of greater-than-or-equal-to 0.2 mum was required in order to obtain a minimum in rho(c). In addition, a metallization of Ti has produced the contacts with the lowest specific contact resistance and the greatest adhesion to the HgTe.