Optical modelling of a-Si : H-based three-terminal three-colour detectors

Optical modelling of transparent conductive oxide (TCO1)/P-I-1-N-I-2-PITCO2 /P-I-3-N/metal superstrate and substrate three-terminal three-colour detect or assembly is performed. There are minor differences between superstrate a nd substrate structure. Simulations indicate that thickness variations of T CO1 layer have the largest effect on the short-wavelength spectral response (blue colour detection). For smooth SnO2:F as TCO1, the optimal thickness is estimated to be 130 nm. Analysis of N layer thickness shows that a thick er N layer (d(N) > 20 nm) improves the blue/green colour separation, but al so decreases spectral response to green colour. In the analysed structures, an optimal thickness of N layer is chosen to be 60 nm. Optimisation of TCO 2 thickness decreases the sensitivity (with smaller interference fringes) o f long-wavelength spectral response (red colour detection) on thickness var iation of I-3 layer. For smooth ZnO:Al as TCO2 the optimal thickness is sim ilar to 150 nm. (C) 2000 Elsevier Science B.V. All rights reserved.