The energetic impact of small Cd Te clusters on Cadmium Telluride

Abstract

Cadmium Telluride (CdTe) is an excellent material for low-cost, high efficiency thin film solar cells. It is important to do research on how these defects are formed during the growth process, since defects lower the efficiency of solar cells. In this work we use computer simulation to predict the growth of a sputter deposited CdTe thin film. Single deposition tests have been performed, to study the behaviour of deposited clusters under different conditions. We deposit a Cd x Te y (x, y = 0, 1) cluster onto the (100) and (111) Cd and Te terminated surfaces with energies ranging from 1 to 40 eV.More than 1,000 simulations have been performed for each of these cases so as to sample the possible deposition positions and to collect sufficient statistics.The results show that Cd atoms are more readily sputtered from the surface than Te atoms and the sticking probability is higher on Te terminated surfaces than Cd terminated surfaces. They also show that increasing the deposition energy typically leads to an increase in the number of atoms sputtered from * M.Yu2@lboro.ac.uk † S.D. Kenny@lboro.ac.uk

Using atomistic simulations to model cadmium telluride thin film growth

“…The CdTe impact energy for magnetron sputtering varies. An earlier study of single molecule depositions by M. Yu et al [27] show that the higher the energy is, the more defects are formed. Therefore we use low deposition energies in our simulations.…”

Modelling the deposition process on the CdTe/CdS interface

“…Early research studies the energetic impacts of individual Cd x Te y (x, y = 50 0, 1) clusters and the growth process on the CdTe surfaces. [14,15] These research helps us understanding the growth of CdTe thin films. It is quite interesting to do more research on the growth process on the CdTe/CdS interface, since these two materials have different lattice constant, and therefore more likely to form defects.…”