PERFORMANCE OF A BRAGG IONIZATION CHAMBER FOR DEPTH PROFILING AND SURFACE ANALYSIS

Abstract The application of Bragg-curve spectroscopy to ERD and RBS is described. In particular, the performance for depth profiling and surface analysis is investigated. Advantages and limitations are discussed. Typical results are good selectivity of the atomic charge number Z up to 20 with a depth resolution on the order of 10 nm and submonolayer sensitivity. An important advantage is the possibility of combining in one measurement the spectroscopy of recoil ions and scattered projectiles. The method is limited by the condition that the energy of the detected particles should be within the operative region of a nearly constant Bragg-peak height. An estimate of this low-energy limit is derived. The low background in the operative region allows the analysis of profiles down to concentrations of about 0.01% of the stoichiometric ones. For different ions the energy calibrations were found to differ by about 3%. The basic ideas and preliminary results of a quantitative analysis of depth profiles are described.

[1]  M. S. Zisman,et al.  Bragg Curve Spectroscopy , 1982 .

[2]  H. Ortlepp,et al.  Bragg peak spectroscopy of low-energy heavy ions , 1987 .

[3]  C. Petersson,et al.  Quantitative mass and energy dispersive elastic recoil spectrometry: Resolution and efficiency considerations , 1987 .

[4]  J. P. Thomas,et al.  Light elements depth-profiling using time-of-flight and energy detection of recoils , 1986 .

[5]  B. Terreault,et al.  An accurate and sensitive method for the determination of the depth distribution of light elements in heavy materials , 1976 .

[6]  F. Gramegna,et al.  Position sensitive and Bragg curve spectroscopy detector system , 1984 .

[7]  R. E. Benenson,et al.  Computer simulation of helium-induced forward-recoil proton spectra for hydrogen concentration determinations , 1986 .

[8]  P. Kienle,et al.  A bragg-curve spectroscopy detector , 1982 .

[9]  A. Oed,et al.  High resolution axial ionization chamber for fission products , 1983 .

[10]  N. Shenhav,et al.  The mass dependence of the signal peak height of a Bragg-curve ionization chamber , 1985 .

[11]  C. N. Davids,et al.  Performance of a large Bragg-curve spectrometer , 1987 .

[12]  K. Kimura,et al.  Particle identification by modified Bragg-curve centroid detection , 1987 .

[13]  J. Duchon,et al.  Performance of a Bragg curve detector for heavy ion identification , 1982 .

[14]  M. Asghar,et al.  Plasma and recombination effects in the fission fragment pulse height defect in a surface barrier detector , 1979 .

[15]  J. Martin,et al.  Time-of-flight system for profiling recoiled light elements , 1983 .

[16]  H. Stelzer.  Gas filled heavy ion detectors , 1983 .

[17]  W. Skorupa,et al.  Properties of buried insulating layers in silicon formed by high dose implantation at 60 keV , 1988 .

[18]  A. Gorski,et al.  A calibration procedure for the response of silicon surface-barrier detectors to heavy ions , 1974 .

[19]  R. Headrick,et al.  A UHV-compatible ΔE−E gas telescope for depth profiling and surface analysis of light elements , 1987 .

[20]  L. Earwaker,et al.  Computer simulation programs for nuclear reaction analysis , 1986 .

[21]  G. J. Wozniak,et al.  Large solid angle Bragg-curve spectrometer , 1984 .

[22]  H. Ortlepp,et al.  REAL TIME DIGITAL PROCESSING OF BRAGG IONIZATION CHAMBER SIGNALS , 1989 .