Wafer Edge Unsalicided Poly Resistor Matching Optimization with Spike Anneal Temperature Control

Rapid Thermal Processing (RTP) is widely used in the world of semiconductor manufacturing. A process which enables rapid heating of samples to high temperatures and capability to perform short processes for a required duration of time. The steep heating rates in the RTP systems are enabled by high intensity lamps through control by thermocouples and pyrometers. A good control of the cooling step must also be handled well to prevent dislocations or sample breakages. This signifies the importance that a good control of precise applied thermal budget is required. In this paper we uncover an improved Spike Anneal Edge Temperature tuning methodology and control to optimize wafer Edge Unsalicided P-Poly Resistor Matching. This tuning methodology relies on the creation of virtual cold zones to counteract the wafer edge steep temperature effect induced by different heat capacity between the wafer and edge ring. An ~80% Edge Yield Recovery was demonstrated after implementation of the improved Spike Anneal tuning Methodology and control.