A quick start

To new TCAD users

• It's recommended to get the basic knowledge of the graphical user interface: sentaurus workbench (swb), about the general usage, including the basic simulation workflow, how to add/remove/modify the variables, how to run the simulation nodes, and how to check the results.

create the project

• The fastest way to start the simulation is to download the compressed file (ChargeCollection.gzp) in the directory ./Example and put it into the work-directory ($STDB) of the TCAD. Unzip the file in the sentaurus workbench (swb), and the simulation project will be ready to use. Here are the steps: setupproject.pdf

• The second method is to create an empty "traditional project" in the swb, download and copy the scripts in the ./Scripts directory into the project file. Setup the simulation tools and assign the scripts to the corresponding tool. This method requires more experience on TCAD.

Run the Simulation

• Generate the device using process simulation: the tool "sprocess". The figure below illustrates the section of the "sprocess" in the swb. The variable names are listed as the header of a table below the icon of the "sprocess" tool. The table contains the values of the variables and the node number.

• To run the process simulation, highlight an experiment or all experiments and click "Run" in the right-click menu. See RunningSimulations.pdf.

• The essential nodes will appear in different colours indicating their status, as depicted in the following figure. The nodes of an experiment is always run from the left to the right, as also shown in the figure, where the left node is in the status "Running" and the right node is in the queue. The reason of this is that the node on the right is in most of the case depending on the output of the node on the left. This sequence is automatically secured when running multiple simulation experiments.

• Double clicking a running node activates the "Node Explore", where the log files output files are summarised (see figure below). In this figure, the output log is being inspected by selecting the file with extension ".out". The viewer is continuously updated for a running node (some times needs to click the "refresh"), so that it is possible to monitor each simulation step. The error messages and the status of the simulation job can also be inspected by selecting the corresponding file. The output files as the simulation results are better be viewed in a different way, which will be introduced later.

Simulation Results

• The output of the process simulation is the geometry of the defined device, and the file extension is ".tdr". In this file, such as the doping concentration and the mechanical stresse distribution in the device can be inspected. For a 2D simulation, the result is a cross section of the device.

• From the device simulation, the diagrams of electrical performances, such as the IV curves, are saved in the files with the extension ".plt". The physical quantities inside the device, such as the potential distribution and the charge carrier density are saved in ".tdr" files.

• There are multiple ways to inspect and extract the simulation results in TCAD, the tools "inspect", "svisual", and the "DataExplorer". The "inspect" only supports the visualisation of the so-called "x-y plots" (".plt" file). The "svisual" supports the visualisation of the ".tdr" file, in addition to the x-y plots. Whilst the "inspect" and "svisual" have GUI, the "DataExplorer" is command-line based, which can be used to extract all the simulated data.

• The example in this repository uses the "svisual" for inspection and extraction of simulation results. The output files can be opened using "svisual" by selecting the function "Visualize" in the right-click menu of the highlighted simulation node (see figure below). The ".plt" file with "Bias" in the file name "Bias" represents the data of DC behaviours of the simulated device. The one with "Signal" contains the data of the transient behaviour of the signal produced by the deposited charge. The ".tdr" file contains the physical characters of the device at the end of the simulation, i.e. after the biasing process and the subsequent charge collection process. Such plots for intermediate steps (including the case before the transient simulation) in the transient simulation can be obtained by uncommenting line 278 or 279 in the simulation script "device_des.cmd".

• The data can be extracted to plots or commonly used data formats by using the GUI or the scripts for all data visualisation tools. As for the "svisual", a tool with the same name can be added and used for automated data processing and extraction (see figure below). The extracted data can be saved to files and/or directly displayed in the swb.