Run a seeded fab model with batches and maintenance
Set the seed, edit batch and preventive maintenance inputs, run the model and compare tool state shares.
Run the seeded batch example, add preventive maintenance and compare the completed run. These steps apply to Cloud 2.1.2.10 and Windows 2.1.2.3.
Open the seeded model
Open the product menu and choose vFactory → Wafer Process & Fab. Select Process models.
In Model, choose Seeded fab simulation (v2). The example starts with seed 17, a 3600-second horizon and the batch-formation dispatch rule.
Set Random seed to a nonnegative integer and Simulation horizon (s) to a positive duration. Keep the same seed and inputs when comparing repeated runs with the same engine.
Edit batches and maintenance
On Cloud, expand Advanced inputs. On Windows, the section controls are already visible. In Model section, choose Equipment, batches, setups, failures and PM.
In Section JSON, review the furnace batch: minSize: 2, maxSize: 4 and maxWaitS: 60. This example counts lots. A batch waits for its minimum size until the oldest waiting lot reaches the maximum wait; available capacity still controls when it starts.
Replace the furnace’s empty pm array with the following array. Leave its other fields in place.
[{"everyS":900,"duration":{"kind":"constant","value":60}}]This requests 60 seconds of maintenance every 900 seconds. For count-based maintenance instead, replace everyS: 900 with everyCount: 2. The default count basis is completed batches. Use exactly one recurrence field.
Select Apply section. To return to the applied values, select Discard section edits. Apply or discard pending edits before running or switching sections.
After Apply section, the furnace keeps its batch settings and has one maintenance entry: 60 seconds every 900 seconds. The seed and the horizon stay at 17 and 3600 seconds.
Run and read the result
Select Run simulation. To stop a running calculation, select Cancel simulation.
When Simulation complete appears, read Computed results, Completed lots and Completed wafers. In Tool state shares, compare processing, maintenance and idle time shares.
Change one input, apply any section edits and run again. Inputs changed marks a displayed result from earlier inputs.
Read Completed lots and Completed wafers, then compare the processing, pm and idle shares in Tool state shares. The values come from the synthetic example inputs.
For the basic process workflow, see Run your first process model in vFactory.
The example inputs are synthetic assumptions, not data from a real fab.