This paper presents the impact of short channel and quantum effects on the MOS transistor mismatch that become more and more important with the drastic reduction of device dimensions. For the first time, an analytical model is proposed for the MOSFET mismatch increase due to short channel effect. Besides, we demonstrate that the inversion layer quantization degrades transistor matching performance. The impact of quantum effect decreases with T-ox, but its relative contribution is enlarged when the gate dielectric thickness is reduced. (C) 2003 Elsevier Science Ltd. All rights reserved.