Spectroscopic ellipsometry and band structure of Si{sub 1{minus}y}C{sub y} alloys grown pseudomorphically on Si (001)
- Ames Lab., IA (United States)
- Univ. of Nebraska, Lincoln, NE (United States)
- International Business Machines Corp., Yorktown Heights, NY (United States). T.J. Watson Research Center
The authors have measured the dielectric functions of three Si{sub 1{minus}y}C{sub y} alloys layers (y {le} 1.4%) grown pseudomorphically on Si (001) substrates using molecular beam epitaxy at low temperatures. From the numerical derivatives of the measured spectra, they determine the critical point energies E{sub 0}{prime} and E{sub 1} as a function of y (y {le} 1.4%) using a comparison with analytical line shapes and analyze these energies in terms of the expected shifts and splittings due to negative hydrostatic pressure, shear stress, and alloying. Their data agree well with the calculated shifts for E{sub 1}, but the E{sub 0}{prime} energies are lower than expected. They discuss their results in comparison with recent tight-binding molecular dynamics simulations by Demkov and Sankey predicting a total breakdown of the virtual-crystal approximation for such alloys.
- Research Organization:
- Ames Lab., Ames, IA (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- W-7405-ENG-82
- OSTI ID:
- 106645
- Report Number(s):
- IS-M-825; CONF-950412-54; ON: DE96000212; TRN: AHC29525%%146
- Resource Relation:
- Conference: Spring meeting of the Materials Research Society (MRS), San Francisco, CA (United States), 17-21 Apr 1995; Other Information: PBD: [1995]
- Country of Publication:
- United States
- Language:
- English
Similar Records
Theory of optical interband transitions in strained Si{sub 1{minus}{ital y}}C{sub {ital y}} grown pseudomorphically on Si (001)
Dielectric function and band gaps of Si{sub 1-x}C{sub x} and Si{sub 1-x}Ge{sub x}C{sub y} semiconductor alloys grown on Si (0 {le} x {le} 0.014)