CMOS/SOI devices are fabricated on Ar+ laser recrystallized polysilicon islands on SiO2 isolating layers. Both N-channel and P-channel MOSFET exhibit good output characteristics. The low field electron and hole mobilities of MOSFET with a channel length of 4 μm are 510cm2/V.s and 142cm2/V.s respectively. 6-stage CMOS inverters have fine static and transient characteristics. 9-stage CMOS ring oscillators with P-channel transistors of （W/L） = （112μm/6μm） and N-channel transistors of （W/L） = （52μm/6μm） are fabricated. The minimum propagation delay is 2.8ns/stage

and the minimum power delay product is 2.6pJ/stage. These speed performance of CMOS/SOI devices are superior to those of the same CMOS devices fabricated on bulk silicon.