Low temperature RTP for BCB curing

• Published in: Microelectronic engineering 2007-11, Vol.84 (11), p.2646-2652
• Main Authors: Ouaknine, Michel, Malik, Igor J., Odera, Masato, Ishigaki, Toshikazu, Ueda, Takeshi, Fukada, Takashi, Yoo, Woo Sik, Soussan, Philippe, Muller, Philippe
• Format: Article
• Language: English
• Subjects: BCB curing; BPSG; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Hot wall chamber; Isothermal cavity; Low temperature thermal processing; Optical sources and standards; Optics; Physics; RTP, rapid thermal processing; SOD anneal
• ISSN: 0167-9317; 1873-5568
• DOI: 10.1016/j.mee.2007.05.033

Rapid thermal processing (RTP) applications are rapidly expanding from the original processes, typically performed above 1000 °C (e.g., post-implant annealing and silicon oxidation) to lower temperature applications such as cobalt and nickel silicide formation with process steps performed as low as 200 °C. The original lamp-based (i.e., “cold wall”) RTP systems, despite their pyrometry-related issues, are [1] still used, even in this low temperature regime. Another problem related to this approach occurs when processing materials exhibit significant outgassing, such as boron-phosphosilicate glass (BPSG). The outgassed vapour can condense on the cold chamber walls and change the light transmission characteristics of the quartz window. This can cause a process shift, uniformity change and will likely increase maintenance. In this paper, an alternative, hot wall approach, based on convection and conductive heat transfer is evaluated for low-temperature curing and annealing of benzocyclobutene (BCB) for high speed digital and microwave applications [2].