Application of Advanced Process Control for IC Manufacturing

Advanced Process Control (APC) has been widely used in IC manufacturing to improve process and device performance. APC can increase the process stability and yield, improve the throughput of process and metrology tools, reduce the cycle time, and reduce consumables, etc. In this paper, we will consider the benefits of run-to-run control technology in semiconductor manufacturing. Many factors can have a negative impact to the final chip yield ratio, while the process control capability will be a high-impact factor. In traditional process control, the process engineers spend a long time in the fab adjusting the process which has very low efficiency and will affect the uptime of the process tool. And the adjustment results also depend on the engineer’s knowledge and experience and sometimes will lead to human errors. For a given process area, it will always need to be adjusted according to tool status, consumables, etc. With APC control, the process engineers only need to embed the algorithms about the process control logic to the system, the control is based on context information like machine, materials, recipes, and layers, etc. We describe product lots run results from the process area, the thermal vacuum deposition (TVD) process. For the TVD application, the advanced process control system drives the thin film thickness to target, which has been proven to be very helpful for process control and uniformity improvement. Run-to-run control will drive the thickness to target, improve the deposition process stability, and reduce the pilot run in a high-volume, high-mix semiconductor manufacturing environment.