clex12.in : Performing a 2D Interconnect Simulation in Clever
Requires: CLEVER
A useful option included within Clever is its ability to operate in 2D or 1D mode. This greatly reduces simulation time and allows the user to check that important aspects of the process are correctly implemented.
This example consists of three layers of metal to illustrate the use of the Cut line feature in order to generate a 2D simulation. The example then goes on to perform the full 3D simulation of the same structure. It will be noted that the 3D simulation takes significantly longer to perform tasks such as the capcitance matrix calculation.
This example also demonstrates the use of the box command which forces Clever to increase the effective mask size by using the given coordinate around the edge of the masks leading to a 3D simulation. This ensures that fringing capacitances are better accounted for by increasing the volume around the perimeter which is meshed therefore increasing the volume within which fringing field lines are solved.
Comparison of the 3D and 2D capacitance matricies yields the expected result of larger capacitances for the 3D simulation. This is because fringing capacitances in the 2D simulation in the Z direction are effectively eliminated. Notice the greatly reduced capacitance in the 2D calculation for non adjacent layers which are effectively shielded in the Z direction. Compare these results with the full 3D simulation where significant fringing capacitance occurs along the length of the structures.
Once the process simulation is complete the three-dimensional structure is saved with the Save statement and can be plotted using TonyPlot3d.
To load and run this example, select the Load button in DeckBuild > Examples. This will copy the input file and any support files to your current working directory. Select the Run button in DeckBuild to execute the example.
Input Deck
go VictoryProcess
##### 2D CALCULATION #####
Init Layout="clex12.lay" Depth=1 Material=Silicon gasheight=10 \
Resolution=0.25 from=0 to=16 at=5.5
## Metal 1 definition ##
Deposit Material=Oxide Thicknes=0.5 Max
Deposit Material=Aluminum Thickness=0.5 Max
Etch Material=Aluminum Thickness=0.5 Max Mask=MET1
Electrodes Mask=MET1 Material=Aluminum
Deposit Material=Oxide Thickness=0.5 Max
## Metal 2 definition ##
Deposit Material=Aluminum Thickness=0.5 Max
Etch Material=Aluminum Thickness=0.5 Max Mask=MET2
Electrodes Mask=MET2 Material=Aluminum
Deposit Oxide Thickness=0.5 Max
## Metal 3 definition ##
Deposit Material=Aluminum Thickness=0.5 Max
Etch Material=Aluminum Thickness=0.5 Max Mask=MET3
Electrodes Mask=MET3 Material=Aluminum
Deposit Oxide Thickness=0.5 Max
save name=clex12_2D
## Create Mesh for 2D Structure ##
go victorymesh
load in=clex12_2D
remesh delaunay
refine region="*" max.size=1
refine regions="aluminum,SiO2" interface.regions="aluminum" \
other.interface.regions="SiO2" grading="quadratic" max.interface.size=0.15
save out=clex12_2D_0.str mode=clever
## Parasitic Extraction ##
go clever
Init Structure="clex12_2D_0.str"
Electrodes Substrate
Interconnect Capacitance AdaptC=0.05
Save Spice="clex12_2D.net"
tonyplot clex12_2D_0.str
##### NOW DO THE SAME CALCULATION IN 3D AND COMPARE #####
go VictoryProcess
Init Layout="clex12.lay" Depth=1 Material=Silicon gasheight=10 Resolution=0.25
Deposit Material=Oxide Thicknes=0.5 Max
## Metal 1 definition ##
Deposit Material=Aluminum Thickness=0.5 Max
Etch Material=Aluminum Thickness=0.5 Max Mask=MET1
Electrodes Mask=MET1 Material=Aluminum
Deposit Material=Oxide Thickness=0.5 Max
## Metal 2 definition ##
Deposit Material=Aluminum Thickness=0.5 Max
Etch Material=Aluminum Thickness=0.5 Max Mask=MET2
Electrodes Mask=MET2 Material=Aluminum
Deposit Oxide Thickness=0.5 Max
## Metal 3 definition ##
Deposit Material=Aluminum Thickness=0.5 Max
Etch Material=Aluminum Thickness=0.5 Max Mask=MET3
Electrodes Mask=MET3 Material=Aluminum
Deposit Oxide Thickness=0.5 Max
save name=clex12_3D
## Create Mesh for 3D Structure ##
go victorymesh
load in=clex12_3D
remesh delaunay
refine region="*" max.size=1
refine regions="aluminum,SiO2" interface.regions="aluminum" \
other.interface.regions="SiO2" grading="quadratic" max.interface.size=0.15
save out=clex12_3D_0.str mode=clever
## Parasitic Extraction ##
go clever
init Structure="clex12_3D_0.str"
Electrodes Substrate
Interconnect Capacitance AdaptC=0.05
Save Spice="clex12_3D.net"
quit