Effect of boron concentration on recombination at the p-Si–Al2O3 interface

Lachlan E. Black, Thomas Allen, Keith R. McIntosh, Andres Cuevas
2014 Journal of Applied Physics  
Articles you may be interested in Deposition temperature independent excellent passivation of highly boron doped silicon emitters by thermal atomic layer deposited Al2O3 We examine the surface passivation properties of Al 2 O 3 deposited on boron-doped planar h100i crystalline silicon surfaces as a function of the boron concentration. Both uniformly doped and diffused surfaces are studied, with surface boron concentrations ranging from 9.2 Â 10 15 to 5.2 Â 10 19 cm À3 . Atmospheric pressure
more » ... ical vapor deposition and thermal atomic layer deposition are used to deposit the Al 2 O 3 films. The surface recombination rate of each sample is determined from photoconductance measurements together with the measured dopant profiles via numerical simulation, using the latest physical models. These values are compared with calculations based on the interface properties determined from capacitance-voltage and conductance measurements. It is found that the fundamental surface recombination velocity of electrons, S n0 , which describes the chemical passivation of the interface, is independent of the surface boron concentration N s for N s 3 Â 10 19 cm À3 , and in excellent agreement with values calculated from the interface state density D it and capture coefficients c n and c p measured on undiffused boron-doped surfaces. We conclude that the physical properties of the Si-Al 2 O 3 interface are independent of the boron dopant concentration over this range. V C 2014 AIP Publishing LLC.
doi:10.1063/1.4867643 fatcat:pekjt4negvdwbjruzjsalkr4j4