Inverter Circuit

M1 OUT IN VDD VDD CMOSP L=0.12u W=1.5u
M2 OUT IN 0 0 CMOSN L=0.12u W=0.48u
VDD VDD 0 1.2

VIN IN 0 AC 0.5
CLOAD OUT 0 20fF

 .OP
 .AC DEC 10 1 100Meg
 .PLOT Vdb(IN) Vdb(OUT)
 .OPTION POST
 .LIB "ibm_013um_model" CMOS_MODELS
 .END