The effects of low temperature buffer layer on the growth of pure Ge on Si(001)

• Published in: Thin solid films Vol. 518; no. 22; pp. 6496 - 6499
• Main Authors: Shin, Keun Wook, Kim, Hyun-Woo, Kim, Jungsub, Yang, Changjae, Lee, Sangsoo, Yoon, Euijoon
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.09.2010; Elsevier
• Subjects: Buffer layers; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Defects and impurities: doping, implantation, distribution, concentration, etc; Density; Exact sciences and technology; Germanium; Low temperature; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Physics; Silicon; Silicon germanides; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Theory and models of film growth; Thickness; Thin film structure and morphology; Thin films; Threading dislocations; Two step growth; UHVCVD; Thickness; Germanium; UHVCVD; Two step growth; Low temperature; Buffer layer; Dislocation density; Threading dislocation; Ge-Si alloys; Growth mechanism; Silicon
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2010.03.148

We investigated the effects of low temperature (LT) Ge buffer layers on the two-step Ge growth by varying the thickness of buffer layers. Whereas the two-step Ge layers using thin (< 40 nm) Ge buffer layers were roughened due to the formation of SiGe alloy, pure and flat Ge layers were grown by using thick (> 50 nm) LT Ge buffer layers. The lowest threading dislocation density of 1.2 × 10 6 cm − 2 was obtained when 80-nm-thick LT Ge buffer layer was used. We concluded that the minimum thickness of buffer layer was required to grow uniform two-step Ge layers on Si and its quality was subject to the thickness of buffer layer.