post layout simulation with spectre

 Hi,

 I am using Calibre PEX to extract netlist for post layout simulation. The output format is spectre.

The way I am following is  that  firstly complete a schematic simulation, then take this simulation as a reference and just need to swap the netlist to the extracted netlist, then perform the layout simulation.

 But there are something weird that when I changed the output node capacitor from 0.1fF to 1uF, the simulation results are almost the same.  

The circuit is an OR gate, the Z port is output. Here are part of the netlist

netlist.pex:

 subckt PM_TDC_or_test\%Z ( 1 2 7 )
c0 ( 7 gnd! ) capacitor c=105453f
c1 ( 2 gnd! ) capacitor c=105453f
r2 ( 2 7 ) resistor r=20.5902
r3 ( 1 7 ) resistor r=9.05844
ends PM_TDC_or_test\%Z

.pxi

  x_PM_TDC_or_test\%Z ( N_Z_M5_d N_Z_M2_d Z )  PM_TDC_or_test\%Z

netlist:

 simulator lang=spectre
include "TDC_or_test.pex.netlist_case.pex"
subckt TDC_or_test (  A B gnd! vdda! Z )
//
// Z    Z
// vdda!        vdda!
// gnd! gnd!
// B    B
// A    A
XM0 ( N_3_M0_d N_A_M0_g N_gnd!_M0_s N_gnd!_M0_b ) NM_33 l=3.5e-07 w=5e-07 \
 ad=1.05e-13 as=1.8e-13 pd=9.2e-07 ps=1.72e-06 nrd=0.42 nrs=0.72 sa=3.6e-07 \
 sb=1.13e-06
XM1 ( N_gnd!_M1_d N_B_M1_g N_3_M0_d N_gnd!_M0_b ) NM_33 l=3.5e-07 w=5e-07 \
 ad=1.8e-13 as=1.05e-13 pd=1.72e-06 ps=9.2e-07 nrd=0.72 nrs=0.42 sa=1.13e-06 \
 sb=3.6e-07
XM2 ( N_Z_M2_d N_3_M2_g N_gnd!_M2_s N_gnd!_M0_b ) NM_33 l=3.5e-07 w=8.75e-07 \                          //output nmos
 ad=3.15e-13 as=3.15e-13 pd=2.47e-06 ps=2.47e-06 nrd=0.411429 nrs=0.411429 \
 sa=3.6e-07 sb=3.6e-07
XM3 ( 6 N_A_M3_g N_vdda!_M3_s N_vdda!_M3_b ) PM_33 l=3.5e-07 w=1e-06 ad=2.1e-13 \
 as=3.6e-13 pd=1.42e-06 ps=2.72e-06 sa=3.6e-07 sb=1.13e-06
XM4 ( N_3_M4_d N_B_M4_g 6 N_vdda!_M3_b ) PM_33 l=3.5e-07 w=1e-06 ad=3.6e-13 \
 as=2.1e-13 pd=2.72e-06 ps=1.42e-06 sa=1.13e-06 sb=3.6e-07
XM5 ( N_Z_M5_d N_3_M5_g N_vdda!_M5_s N_vdda!_M3_b ) PM_33 l=3.5e-07 w=1.75e-06 \                           //output pmos
 ad=6.3e-13 as=6.3e-13 pd=4.22e-06 ps=4.22e-06 sa=3.6e-07 sb=3.6e-07
c_1 ( 6 gnd! ) capacitor c=0.0955951f
//
include "TDC_or_test.pex.netlist_case.TDC_or_test.pxi"
//
ends TDC_or_test

It seems that the "gnd!" node in .pex file is floating. So I changed the netlist to below, then it works fine. But in spectre a net ends with "!" means a global net, but why it can't be recognised? or something I missed?

 Any reply will be appreciated!

netlist.pex:

 subckt PM_TDC_or_test\%Z ( 1 2 7 gnd! )
c0 ( 7 gnd! ) capacitor c=105453f
c1 ( 2 gnd! ) capacitor c=105453f
r2 ( 2 7 ) resistor r=20.5902
r3 ( 1 7 ) resistor r=9.05844
ends PM_TDC_or_test\%Z

.pxi

  x_PM_TDC_or_test\%Z ( N_Z_M5_d N_Z_M2_d Z  gnd! )  PM_TDC_or_test\%Z

PS:  I am using IC6.1 .5-64b