With demand for semiconductor wafers exceeding manufacturing capacity, Integrated Device Technology (IDT, Hillsboro, Ore.) rushed to construct a new submicron, Class 1 fabrication facility or "fab." In the meantime, the company spent $30 million to upgrade a 10-year-old facility to boost production while waiting for completion of the new plant. In addition to speedy construction, IDT also needed to stay within its $1,750/square-foot budget— significantly lower than the average $4,000/square-foot cost of a new fab. To help meet cost and speed constraints, without compromising cleanroom specifications, IDT contacted project integrator, Industra Inc. (Portland, Ore.) to develop and install an automated monitoring and control system from GE Fanuc Automation (Charlottesville, Va.).

Strict cleanroom specifications have the potential to complicate and lengthen new fab construction as well as mire production and escalate downtime in the completed facility. To prevent this, Industra installed the system within a tight nine-month deadline. Early in the project, IDT and Industra debated control architecture and the number of GE Fanuc Series 90-30 PLCs. Due to the short construction schedule, the control team decided that a common panel design would be the fastest and least expensive to build. Industra designed a single panel with space for three CPUs and issued fabrication drawings to the panel shop one week after project kickoff. The fast-track schedule forced early decisions on panel placement, I/O layouts, and I/O assignments.

Industra implemented the facility controls on a staggered schedule. Temporary equipment was installed when deliveries did not meet construction deadlines. Construction focused on dividing the cleanroom into "zones" and bringing them online in a designated sequence. This required the facility energy center to be online early, and air handlers, make-up air handlers, terminal units, and cleanroom modules were to be commissioned in a parallel schedule. After installing the first bay's equipment and instrumentation, the team completed subsequent zones in quick succession. Checkout and commissioning occurred in one area while installation took place in another. Startup was handled system by system.

After all systems were running, technicians set up the facility with preliminary tuning. The control system permits modifications and refinement as the fab continues to grow and change. This meant that during each construction phase, screens for Cimplicity HMI—the supervisory control and data acquisition (SCADA) software used in the project—could be developed on the fly. If a problem occurred during expansion, the team then modified the control screens to accommodate more data or control points to solve the problem.

Today, the GE Fanuc monitoring and control system has scaled up to encompass every control function in the facility. Along with reliability and scalability, economy has also been realized. The cost of installing the system was one-third the expense of a conventional distributed control installation. The original project was estimated at $1,200 per I/O point, including hardware, software, installation, and engineering. This initial investment has yielded returns to make the IDT Winfab one of the most cost-effective, competitive fabs in the Pacific Northwest.

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For more information on GE Fanuc, for Industra, visit www.controleng.com/info