Calculate a MOS capacitor C–V curve

Apply ideal Si/SiO₂ capacitor inputs, calculate LF and HF capacitance per unit area, and save a MOS-C project document.

Before you start

These steps apply to Cloud 2.1.2.10 and Windows 2.1.2.3.

The MOS-C model calculates an ideal one-dimensional Si/SiO₂ capacitor locally, with charge and capacitance per unit area.

On Cloud, stop the project runtime before running the device calculation and saving or opening project documents.

Set the capacitor inputs

  1. In the window header, open the product menu and choose vFactory > Wafer Process & Fab. Select Process models, then Device (MOS-C).

  2. In MOS-C inputs (SI), choose p or n under Substrate type. Enter Substrate doping (m⁻³), Oxide thickness (m), Work-function difference (V) and Temperature (K).

  3. Enter Mesh nodes (33–129) and comma-separated values in Increasing gate voltages (V). Use 1–32 increasing voltages within 3 V of the work-function difference.

  4. Select Apply inputs. To edit the full request, expand Advanced inputs and edit Request JSON (SI).

Run and read the results

  1. Select Run MOS-C simulation. During the calculation, select Cancel MOS-C simulation to stop it.

  2. Read LF / HF capacitance–voltage in F/m², Surface potential (V) and Semiconductor charge (C/m²). The summary shows the flat-band voltage, threshold voltage and oxide capacitance per unit area.

  3. Read Computed points and convergence for each gate voltage, LF/HF capacitance, region, iterations and residual.

  4. Expand Execution provenance and assumptions to inspect the input, result and engine hashes, source revision, mesh and model assumptions.

Save and open a project document

  1. Keep the project used for this calculation selected, with project file access enabled.

  2. Select Save MOS-C to project. For the first save, enter a new name in Project document filename, then select Save project document. Keep the .alcad-device-mos.json filename ending on Windows; Cloud adds this ending when you enter a bare name.

  3. Select Save MOS-C to project again to update the opened or saved file. To create another file, select Save MOS-C as project file, enter a new filename and select Save project document.

  4. Select Open MOS-C from project, choose the file in Project document, and select Open project document. If a draft is unsaved, select Replace the current unsaved draft with this file. before opening it.

Run your first process model in vFactory