Energy band diagram near the interface of aluminum oxide on p-Si fabricated by atomic layer deposition without/with rapid thermal cycle annealing determined by capacitance-voltage measurements

Abstract

We evaluated the fixed charge (Qf) and the interface state density (Dit) from the capacitance-voltage (C-V) measurement before and after rapid thermal cycle annealing (RTCA) using p-type silicon in which the passivation was performed with aluminum oxide (Al2O3) film by atomic layer deposition (ALD). From C-V measurement we obtained the surface potential (VS), accumulation and depletion width, and as a result, energy band diagrams were produced. It was determined that a barrier height of approximately 100 mV was induced by fixed negative chargesin the Al 2O3 layer near the interface to the p-type Si substrate. The field effect of the Al2O3 passivation layer created by RTCA strongly remains without depending on the gate voltage (VG). © 2012 The Surface Science Society of Japan.