Many customers ask for vacuum RTP because they believe vacuum means cleaner processing, lower oxygen, or better performance. Based on more than 45 years of RTP experience, Allwin21 recommends atmospheric RTP for most standard RTP applications unless the process truly requires reduced pressure.
Cleaner, Serviceable Process Chamber
Allwin21 Atmospheric RTP uses an isolated removable quartz tube. Process deposits can be managed by removing the quartz tube for cleaning or replacement. Contamination inside a metal vacuum chamber can be more difficult and costly to remove.
Non-Contact ERP + Top/Bottom Heating
Allwin21 atmospheric RTP combines 6- to 10-zone top-and-bottom infrared lamp heating with a patented ERP non-contact pyrometer for high-temperature RTP performance and greater process flexibility—an important advantage over vacuum RTP, where ERP temperature measurement is not available.
Low O₂ Without Vacuum
Forming gas purge can achieve approximately 5–25 ppm O₂ in Allwin21 atmospheric RTP for O₂-sensitive applications. This approach has been proven by many compound semiconductor customers. Low O₂ does not automatically require vacuum.
When should you choose vacuum RTP? When reduced pressure itself is required by the process. If the process does not require reduced pressure, Allwin21 normally recommends a proven atmospheric RTP platform.