Impact of Environmental Air Pressures on Ion Implant Particle Performance

Numerous methodologies are available to evaluate particle performance for batch implanters. In this case, a single control wafer used to measure sheet resistance for varying dopant species is also monitored for particle adders using the KLA SP1 metrology tool with a frequency of three times per week. In addition, a full batch of 17 wafers implanted with argon is similarly monitored with the same frequency on alternating days. The benefits of using argon include reduced species cross-contamination and lower costs because of gas usage. This dual testing strategy allows us to capture multiple sources of variation, including day-to-day, species-to-species, and slot-to-slot variation. The resulting data allows for detailed analysis of most, if not all, relevant factors involved in a standard process.