Advances in SiGeSn Technology
Abstract
We recently reported the CVD growth of binary Ge(1-y)Sn(y) and ternary Ge(1-y)Si(x)Sn(y) alloys directly on Si wafers using SnD(4), Ge(2)H(6) (di-germane), SiH(3)GeH(3), and (GeH(3))(2)SiH(2) sources. Ge(y)Sn(y) is an intriguing infrared material that undergoes an indirect-to-direct bandgap transition for y < 0.1. In addition, we have found that Ge(1-y)Sn(y) layers have ideal properties as templates for the subsequent deposition of other semiconductors: (a) they are strain-relaxed and have low threading-defect densities (105 cm-2) even for films thinner than 1 micrometer; (b) their low growth temperatures between 250 deg C and 350 deg C are compatible with selective growth, and the films possess the necessary thermal stability for conventional semiconductor processing (up to 750 deg C depending on composition); (c) they exhibit tunable lattice constants between 5.65 A and at least 5.8 A matching InGaAs and related III-V systems; (d) their surfaces are extremely flat; (e) they grow selectively on Si and not on SiO(2); and (f) the film surface can be prepared by simple chemical cleaning for subsequent ex-situ epitaxy.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 2007
- Accession Number
- ADA483415
Entities
People
- John Kouvetakis
- John Tolle
- Jose Menendez
- Richard Soref
- Vijay D'costa
Organizations
- Air Force Research Laboratory