Synopsys Sentaurus Tutorial
- For EE 130/230M Project
Dr. Nuo Xu
Spring 2013
CONFIDENTIAL INFORMATION
– The following material is being disclosed to you
pursuant to a non-disclosure agreement between
UC Berkley and Synopsys. Information disclosed
in this presentation may be used only as permitted
under such an agreement.
LEGAL NOTICE
– Information contained in this presentation reflects
Synopsys plans as of the date of this presentation.
Such plans are subject to completion and are
subject to change. Products may be offered and
purchased only pursuant to an authorized quote
and purchase order. Synopsys is not obligated to
develop the software with the features and
functionality discussed in the materials.
Outline
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Software Setups and Configurations
Introduction to Sentaurus TCAD
Basic Sentaurus Operations
Project Tips
Software Setups
• X11 Forwarding Software (i.e. Exceed)
Successful running will display a
task bar on your desktop
Exceed helps you forward the
GUIs from Unix system to your
PC
Software Setups
• You may also use Xming that is loaded on the
computer lab (1st floor of Cory Hall).
• Putty
Putty is a remote login software, will
help you to log into Unix system
from a PC (Windows)
• WinSCP
WinSCP can be downloaded online,
for free, and is used to transfer files
from your PC to the Unix.
Servers and Performance
• Instructional servers (login with the instructional
accounts):
 pulsar.eecs.berkeley.edu
 quasar.eecs.berkeley.edu
 c199.eecs.berkeley.edu
• Shared servers are going to be slow, due to the
multiple-thread tasking.
 Do not wait until the last day!
• For those who want to WFH: The connection speed is
going to be slow, if you are off campus and do the direct
forwarding from the servers.
 My suggestion: leave a computer on campus
running Sentaurus and remote log into it.
Configurations
• .cshrc file
 A system configuration file under your folder, to
define all the environmental variables needed in
Unix system
 Append the following codes to the bottom of your
existing .cshrc file:
setenv LM_LICENSE_FILE 27005@license-srv.eecs.berkeley.edu
set path = ($path /usr/eesww/synopsys/G_2012.06/bin)
setenv STDB $HOME/SYNOPSYS/STDB
•
X11 Forwarding
 Make sure you have enabled the X11 forwarding
option in putty.
Please check here !
Running Sentaurus
• Start Exceed or Xming
• Start putty
 Select the server you want to run your simulation
 Log on the server
 Input your Account name and Password
After you enter your login name, the system
displays “Access Denied”. Ignore it and go
ahead to enter your password.
Transfer of Project Folder to Unix
• Copy the project folder provided on the project
link of class website to the instructional server by
using WinSCP (see next page).
• After transferring the folder, type:
scp -r Project username@pulsar.eecs.berkeley.edu
This command will copy the Project folder into yout
home directory
Once you have logged in,
you can view the files in both
your PC and the home
directory of the server
Log in using your
instructional account!
Just select the files/folder
from your PC and copy to
the server
- After login and file transfer, go back to your
Putty window.
- It’s recommended that you first check whether
you have correctly configured your simulation.
So type “which swb”
It tells you the installation path of Sentaurus.
- Then, type “swb” to start Sentaurus workbench.
Running Sentaurus on ilinux1
1. Copy project folder:
scp –r project_dir username@ilinux1.eecs.berkeley.edu
2. Login:
ssh -X username@ilinux1.eecs.berkeley.edu
3. Make a new directory at your home directory with:
mkdir ee130_project
4. Copy the project folder in this newly made direcoty with:
cp –r 20nm-NMOS-EE130 ee130_project
5. Start Sentaurus with the command at the home directory:
/share/b/bin/swb
You do not need to modify .cshrc file.
6. Once Sentaurus starts, first, from the left panel right click->project->unlock
Then double click the project to see the modules loaded on the workbench. Now you
can preprocess, run and visualize the results.
For Windows:
•install MobaXterm from http://mobaxterm.mobatek.net/.
On MobaXterm, you have a unix like command line using which you can login using
the same unix like commands as above.
Sentaurus Workbench
• Run command: swb
• Graphical user interface to unify all simulation tools
into a single experiment project flow
• Used to organize projects and set up experiments
for both structure generation and device simulation
Technology Computer-Aided-Design Tools
Parameter row
Experiment column
Unlocking Workbench
• Double click 20nm-NMOS: the simulation modules
will show up on the work bench
• If you cannot edit the value in the cell, then Right
click 20nm-NMOS→ project→unlock :This will
unlock the project for modification of values.
Technology Computer-Aided-Design Tools
Parameter row
Experiment column
Sentaurus Structure Editor
• Recommended to run in workbench
• Run command (under putty): sde
• Structure Editor (1) generates the device
structure (including the doping profiles) (2)
Defines the electrical contact and (3)
generates the meshing for numerical
simulations.
Parameters you may need to change/optimize for this project
• Gate oxide thickness (Xo, Units: um)
• MOSFET gate length (Lgate, Units: um)
• Spacer length (Lsp, Units: um)
• Channel Doping Concentration (ChanDoping, Units: cm-3)
• Source/Drain extension depth (XjExt, Units: um)
Sentaurus Device
• Recommended to run in workbench
• Run command (under putty): sdevice
• Sentaurus Device simulates the device
performance by solving multiple, coupled
physical equations based on the meshing.
• Inputs: gate voltage (Vgs), drain voltage
(Vds), workfunction value
Common Physical models:
• Si band structure (Ec/v, Nc/v and bandgap narrowing)
• Fermi-Dirac Statistics
• Poisson equation, continuity equation
• Band-to-band tunneling, R-G current
• Drift-Diffusion current, carrier mobility, velocity saturation
Sentaurus Inspect
• Recommended to run in workbench
• Used to automatically extract critical
device performance parameters such as:
Vt_lin
Id_lin
Vt_sat
Id_sat
I_OFF
• Also used to plot the Id-Vg and Id-Vd
curves
Simulation Status
• Start Sentaurus, first select from the left project
column, right-click to “preprocess”.
• Then you will find the nodes will display different
colors, suggesting they have different properties.
Here is a summary. Only colorful nodes will give
you the simulation output.
• “Ready” means the current tool is free of syntax
errors (You should see this since you are not
allowed to modify the scripts).
• Right-click a certain Ready nodes to run, after a
short period of time, you will find it changes to
“done” or “failed”.
Basic Operations for
Sentaurus Structure Editor
• Now you can view your simulation results if the
nodes are done.
• Right-click the node in Structure editor, select
Visualize → Tecplot SV (Select File) and choose
msh.tdr file to view your device structure.
This is the gate
position, only gate
contact is left
1-dimensional
contact
By default, doping
concentration is
displayed
Basic Operations for
Sentaurus Tecplot
• This slide help you familiarize the usage of Sentaurus
Tecplot, this tool is for the visualization and
profiles/contours extraction purposes.
zoom-in tool
Slice-cutting
display
adjustment
Default units:
um
Export the results from Tecplot:
As an image (.bmp)
To get the data field,
first, use Y-cut to get
the 1-D slice; then
select
export
→
Inspect graph
Then Inspect will be started.
Select the data field herein; Click
File → Export → txt file
You can read your saved data (.txt file)
from your project directory
Basic Operations for
Sentaurus Device
• Right-click the “done” node in Structure Device,
select Visualize → Tecplot SV (Select File) and
choose des.tdr file to view your device performance
contours (vector fields).
Current Density
Linear region
Saturation region
Basic Operations for
Sentaurus Device Cont.’d
• Right-click the “done” node in Structure Device,
select Visualize → Inspect (Select File) and choose
IdVg_des.plt file to view your device performance
curves.
Device
Terminals
Choose Log Y or
Linear Y here
Most common plot
combination is “gate:
OuterVoltage”
Outputs
Use cursors to read
the data value along
“drain: TotalCurrent”
the curve
Project Tips
• Typical Performance Figure-of-Merits
• Performance Specifications for this Project
• Performance Optimization Hints for a
Short-Channel MOSFET
Idsat, Ilin and IOFF
Vds=VDD
Idsat
Vds=20mV
IOFF
Ilin
IOFF, Idsat and Idlin
are
extracted
automatically
VDD
Threshold Voltage (Vt)
Constant current definition
of threshold voltage
It = 100nA · W/Lgate
W has default value of 1um for
2-dimensional device simulation
Vth
Vtlin and Vtsat are
extracted
automatically
DIBL and SS
DIBL is defined as the threshold
voltage difference divided by the
drain bias between linear and
saturation region .
Sub-threshold Swing
You are required to extract S
and DIBL manually, from
your optimized device !
Performance Specifications
• For students taking EE130, your goal is for the Low-Operating
Power (LOP) technology; and you have to meet the following
specs (at 20nm node):
- IOFF should be smaller than 1 nA/um.
- ION should be larger than 400 uA/um.
LOP Products: ~16% of Semi. mkt
• For students taking EE230M, your goal is for the Low-Standby Power (LSTP) technology; and you have to meet the
following specs (at 20 nm node):
- IOFF should be smaller than 10 pA/um.
- ION should be larger than 250 uA/um.
LSTP Products: nowadays >20% of Semi. mkt
Hints for Your Optimizations
• Impacts of channel doping concentration (Nch): Increasing
Nch generally helps to reduce IOFF, until it touches the bandto-band tunneling limits. On the other hand, high Nch will
degrade the carrier mobility values, resulting in a low ION.
• Impacts of Junction Depth (Xj): smaller extension Xj helps
to reduce IOFF, however it will result in a larger Source/Drain
series resistance value to degrade ION.
• Impacts of SiN spacer width (Lsp): Wider spacer helps to
reduce the impact from deep Source/Drain regions;
however it will also result in the larger series resistance
problem.
 So as you can see, there exist trade-offs to optimize
ION/IOFF ☺
Project Hints
• Since our performance targets are mainly for ION and IOFF,
so you should start working on the saturation-region device
simulation first.
• Once you are able to meet the specs, then you should
perform the linear-region device simulation to get the
current and threshold voltage values, as well as to measure
the DIBL value.
Project Hints (Con’d)
• The next task is to study the Short-Channel Effect, by
changing the gate length ONLY. Perform the simulations in
both linear and saturation regions, and then plot the
threshold voltage values vs. gate length.
 Refer to Lecture 22, Slide 12.
• Lastly, you should run the last SDevice component, to
generate the Ids vs. Vds curves under 4 Vgs values. Then
take a look at the I-V curves to decide whether your device
performance is limited by the “pinch-off” or the carrier
velocity saturation.
 How to determine this? Refer to Lecture 22 Slide 10
Q&A
Please
- come to Dr. Xu’s office hours (Mon 12-1PM & Tue
3-4PM) OR
- send him emails
(nuoxu@eecs.berkeley.edu) OR
- Post a question note on Piazza
for any technical issues/problems.