Sim4all – A System for Generating Factory Simulations by Non-Expert Users

The semiconductor manufacturing environment is a unique one. It is characterized by an inherent high variability in its process, emanating from equipment availability and a highly re-entrant process flow, along with a very long process typically containing hundreds of sequential process steps performed by shared toolsets subject to unique restrictions such as step dedications, dynamic lock-outs of tools to steps, queue time (also known as process time window) limitations, etc. Static capacity models do not support the evaluation of aggregated impact of most of these factors, and only full Fab simulation model can provide reliable forecasts of fab-level indicators (such as WIP and output), and toolset-level ones (such as Cycle Time and X-Factor). Full Fab simulation supports analyses of various fab-wide what-if scenarios and helps evaluate the impact of tool depreciation efforts and cost saving projects, providing critical insight and clear guidance for decision makers.

Previously, full fab simulation analysis capabilities were limited to trained experts only. This introduced a skills bottleneck meaning that only the highest priority requests were addressed and even those had a very slow turnaround time with engineers often waiting for weeks before getting the analysis they required. As a result other yield and cost reduction projects were either overlooked or delayed beyond the relevant time-frame.

Sim4All is a new information system that provides a solution to this problem, by allowing non-experts to run their own experimental scenarios and get full results within a single day. This system replaces the current slow and tricky process of creating a simulation using text input and output files. Sim4All system has a user friendly web interface that allows anyone to edit or create simulation experiments for example: add or remove a tool, change process times, edit tool-operation qualification matrix etc. After user creates the required scenario, his data entries are then validated and automatically run on the server side web framework. Once the experiment is completed the user is then able to download the results and analyse them using a custom-built one click interface. All of this is done within one day by any user without the need for a simulation expert (hence the name of the system, “Sim4All”).

In addition to alleviating the simulation expert constraint and allowing to generate more simulation scenarios more quickly, Sim4All also improves data quality of the simulation, by replacing tedious manual data entry with automatic data generation and validation.