Conventional Si or SiGe epitaxy via chemical vapor deposition is performed at high temperatures with a large amount of hydrogen gas using silane (SiH4) or dichlorosilane (SiCl2 H2) precursors. These conventional precursors show low growth rates at low temperatures, particularly below 500◦ C although a low thermal budget becomes more important for modern fabrication techniques. High-order silane precursors, such as disilane, trisilane, and tetrasilane, are candidates for low-temperature epitaxy due to the lower strength of the Si-Si bonds compared to that of the Si-H bonds. In addition, the consumption of vast amounts of hydrogen gas is an additional burden of the low-temperature process due to its low throughput. In this study, we explored Si and SiGe epitaxial growth behaviors using several high-order silanes under ultra-high vacuum chemical vapor deposition (UHVCVD) and low-pressure chemical vapor deposition (LPCVD) conditions without a carrier gas. Disilane showed high-quality epi-growth under both pressure conditions, whereas trisilane and tetrasilane showed enhanced growth rates and lower quality.
Bibliographical noteFunding Information:
Funding: This work was supported by the Technology Innovation Program (20010598) funded by the Ministry of Trade, Industry & Energy (MOTIE), and the Future Semiconductor Device Technology Development Program (20004274) funded by MOTIE and Korea Semiconductor Research Consortium (KSRC).
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.
All Science Journal Classification (ASJC) codes
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Materials Chemistry