AVS 45th International Symposium
    Electronic Materials and Processing Division Wednesday Sessions
       Session EM-WeM

Paper EM-WeM4
A Reduced Carbon Contaminant, Very Low-Temperature Silicon Substrate Preparation for Defect-Free Homoepitaxy

Wednesday, November 4, 1998, 9:20 am, Room 316

Session: Fundamentals of Si Cleaning and CMP
Presenter: P.J. Taylor, University of Virginia
Authors: P.J. Taylor, University of Virginia
W.A. Jesser, University of Virginia
M. Martinka, US Army CECOM-Night Vision and Electronic Sensors Directorate
K. Singley, US Army CECOM-Night Vision and Electronic Sensors Directorate
J. Dinan, US Army CECOM-Night Vision and Electronic Sensors Directorate
R. Lareau, US Army Research Laboratory
M. Wood, US Army Research Laboratory
W.W. Clark III, US Army Research Laboratory
Correspondent: Click to Email
A low-temperature cleaning technique incorporating an ultraviolet lightozone treatment with conventional hydrogen-passivation techniques is shown to yield record-low concentrations of surface contaminants: @>=@ 0.01 monolayer (ML). An additional advantage is that no Atwater-type@footnote 1@ UHV prebaking treatments are required for substrates receiving this treatment prior to epitaxy. Low-temperature silicon molecular beam epitaxy (MBE) on such substrates is characterized by a threading dislocation density on the order of 10@super 4@/cm@super 2@ (Schimmel etching@footnote 2@) which is a reduced threading dislocation density compared to that measured from films receiving more conventional hydrogen-passivation preparation techniques: typically between 10@super 5@/cm@super 2@ and 10@super 6@/cm@super 2@.@footnote 3@ The interfacial contamination was measured before homoepitaxy by in-situ Auger electron spectroscopy (AES) and after homoepitaxy using secondary-ion-massspectroscopy (SIMS). The results of this study suggest that aqueous solutions are a significant source of surface carbon and that an ultraviolet light-ozone treatment before hydrogen passivation is particularly efficacious for removing residual carbon on the silicon surface which would otherwise contribute to the generation of threading dislocations in Si homoepitaxial films. @FootnoteText@ @footnote 1@Nikzad, S., Wong, S., Ahn, C., Smith, A., Atwater, H., Appl. Phys. Lett. Vol. 63(10) p. 1414 (1993). @footnote 2@Schimmel, D., Journ. Electrochem. Soc., Vol. 126 p. 479 (1979). @footnote 3@Eaglesham, D., Higashi, G., Cerullo, M., Appl. Phys. Lett., Vol. 59(6) p. 685 (1991).