A simple phenomenological model for the interpretation of ion neutralization spectra
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A548 Surface Science 161 (1985) 479-490 479 North-Holland, Amsterdam SURFACE GRAPHITIZATION PROCESS OF SIC(0001) SINGLE- CRYSTAL AT ELEVATED TEMPERATURES Seilt ADACHI, Mamoru MOHRI and Toshiro YAMASHINA Department of Nuclear Engineering, Faculty of Engineering, Hokkatdo Umvers:tv, Sapporo 060, Japan Received 6 February 1985, accepted for publication 31 May 1985 The SIC(0001) single-crystal has been studied in terms of changes in surface composition m the temperature range of 980-1300°C by means of Auger electron spectroscopy (AES) The carbon concentration at the surface increased with temperature Tlus increase was split up Into two processes One was an initial fast process and the next was a slow one, observed above 1000°C It was concluded that the former was thermodynamic and that the latter was caused by evaporation of sdlcon atoms Activation energies for the slow process of surface grapbattzatlon and for evaporation of slhcon, which erasted in the near-surface region before heat treatment, were found to be 1 1 and 3 4 eV, respectively Surface Science 161 (1985) 491-512 North-Holland, Amsterdam A SIMPLE PHENOMENOLOGICAL MODEL FOR THE INTERPRETATION OF ION NEUTRALIZATION SPECTRA Eric HOOD * No~es Laboratory of Chemical Ph~sws, Cahfornta Institute of Technology, Pasadena. Cahforma 91106. USA Ferenc BOZSO ** Department of Chem:sto, Pittsburgh University, Pittsburgh. Pennsl lt,an:a 15260, USA and Horla METIU *** Department of Chemtstrx', Untt,erstty of Cahfornta, Santa Barbara, Cahforma 93106, USA Received 15 October 1984. accepted for pubhcatton 7 May 1985 491 We present here a simple model for the mterpretatlon of ton neutrahzatton spectra We take into account the fact that the neutralization process depends on both the density of states and the orbital size and takes place continuously at all surface-ion separation distances at wtuch the ton and metal orbltals overlap. The model ts apphed to the calculation of the density of states of the NI(111) surface
Transcript of A simple phenomenological model for the interpretation of ion neutralization spectra
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Surface Science 161 (1985) 479-490 479 North-Holland, Amsterdam
S U R F A C E G R A P H I T I Z A T I O N P R O C E S S O F S I C ( 0 0 0 1 ) S I N G L E -
C R Y S T A L A T E L E V A T E D T E M P E R A T U R E S
Sei l t A D A C H I , M a m o r u M O H R I a n d T o s h i r o Y A M A S H I N A
Department of Nuclear Engineering, Faculty of Engineering, Hokkatdo Umvers:tv, Sapporo 060, Japan
Received 6 February 1985, accepted for publication 31 May 1985
The SIC(0001) single-crystal has been studied in terms of changes in surface composition m the temperature range of 980-1300°C by means of Auger electron spectroscopy (AES) The carbon concentration at the surface increased with temperature Tlus increase was split up Into two processes One was an initial fast process and the next was a slow one, observed above 1000°C It was concluded that the former was thermodynamic and that the latter was caused by evaporation of sdlcon atoms Activation energies for the slow process of surface grapbattzatlon and for evaporation of slhcon, which erasted in the near-surface region before heat treatment, were found to be 1 1 and 3 4 eV, respectively
Surface Science 161 (1985) 491-512 North-Holland, Amsterdam
A S I M P L E P H E N O M E N O L O G I C A L M O D E L F O R T H E
I N T E R P R E T A T I O N O F I O N N E U T R A L I Z A T I O N S P E C T R A
E r i c H O O D *
No~es Laboratory of Chemical Ph~ sws, Cahfornta Institute of Technology, Pasadena. Cahforma 91106. USA
F e r e n c B O Z S O **
Department of Chem:sto, Pittsburgh University, Pittsburgh. Pennsl lt,an:a 15260, USA a n d
H o r l a M E T I U * * *
Department of Chemtstrx', Untt,erstty of Cahfornta, Santa Barbara, Cahforma 93106, USA Received 15 October 1984. accepted for pubhcatton 7 May 1985
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We present here a simple model for the mterpretatlon of ton neutrahzatton spectra We take into account the fact that the neutralization process depends on both the density of states and the orbital size and takes place continuously at all surface- ion separation distances at wtuch the ton and metal orbltals overlap. The model ts apphed to the calculation of the density of states of the NI(111) surface
