Band Diagram Program Version 2
Shared by: undul855
Band Diagram Program Version 2.1.1 Bugs Fixed Would not update some of the stack parameters, an option accessible from the “View” menu, if the structure had two materials of the same name. This issue has been resolved Viewing the Semiconductor materials under “View” -> “Materials” -> “Semiconductors” showed the material properties out of order. This has been fixed. If two materials were added under the same name the program would get confused on which material the user selected. To correct this, the user is not allowed to add materials with the same name to the databases. For n-type semiconductors, the semiconductor capacitance was displayed negative. The value now reads positive. For n-type semiconductors, the surface potential was limited to the band gap which caused the surface potential to pin at high voltages. The allowed values for the surface potential has been increased to stop it from pinning. For n-type semiconductors, the charge calculated in the semiconductor is incorrect. This has been fixed. For biases near flat band, the charge in the semiconductor as a function of distance is incorrect. This has been fixed. Updates Added shortcut keys for many common options. Added an unlimited “Undo” option (accessible from the edit menu or Ctrl-z). Added quick access to various structure parameters by double clicking on the material of interest. Added quick removal and addition of materials through a contextual menu (right click on the diagram) Added a movie button (on the toolbar) where the structure is shown moving from one voltage to another. Can edit the movie options and optionally save various outputs (Gate Voltage, potential, electric field, surface potential etc) through the menu item “Movie Parameters…” accessible through the “View” menu. The parameters at each of the gate voltages for the movie are stored as a csv (comma separated data) file. Added the option to manually define the viewing window. Accessible under the “View” menu and the menu item “View Window…” or Alt-V. Under this window various auto scale options can be picked. Program now loads with a default structure. The user can define the default structure by making the structure of choice and then clicking the menu item “Save as default” under the “File” menu. Program will now prompt the user to save the structure before closing it if it has detected any change. Note: if the voltage has changed some internal parts of the structure have been changed and so a save prompt will be issued. Program will now prompt the user to save the database files (*.dat files that store the materials parameters of the dielectrics, metals, and semiconductors) if it has detected a change. Program will now save the state of various options and reload them the next time the program runs. Such options include the gate voltage, whether to show or hide the stack parameters and the new movie parameters. For the Microsoft Windows® version of the program, an installer has been created to simplify program setup and removal as well as designating it as the default program for *.bds (band diagram structure) files. A program shortcut is installed under “Start-All Programs”. The metals, dielectrics, and semiconductors databases have been expanded to include more materials. Added the ability to sort the materials by Name, Notes, and Parameters. Added a calculated threshold voltage – the voltage required to move the Fermi- level in the semiconductor to -ϕ F. ϕ F is the body doping potential. Added the tunneling distance (currently only available by exporting the parameters calculated during the movie). Can now export charge, electric field, and potential plots in addition to energy band plots. Changed the way charge is displayed in the semiconductor. It is now given in units of C/cm3 instead of awkwardly spaced line charges (C/cm2) which didn’t represent the distribution of charges very well. Known Bugs: For complex charge trapping in the dielectric the calculated tunneling distance may error. This will occur if the conduction/valance band of the dielectric crosses the tunneling energy level twice.