Core-level shift of the In 4d line for a clean InP(001)-2 x 4 surface

Abstract

The core-level shift of the In 4d line has been studied for a clean InP(001). The surface of a sample of polished Cd-doped p-type InP(001) was sputtered by Ar(+) ion at 500 eV and subsequently annealed at 350 C so that no carbon and oxygen were detected and that the sharp (2 x 4) LEED (Low-Energy Electron Diffraction) pattern was observed. The surface core level shifts of the In 4d level were measured at various detecting angles, theta, (from 15 deg to 84 deg). In 4d spectra of the clean (2 x 4) surface for various detecting angles were shown in figures. The spectra were divided into four components (S1, S2, S3 and B), and the changes in intensity ratio of these four components for the various theta have been discussed for respective components. The intensity of component S1 was found to increase exponentially with the increase of angle, while that of component B decreased largely with the increase of angle. The intensities of components S2 and S3 were increased first and subsequently decreased as the angle increased.

清浄なInP(001)について、Inの4d線のコア準位偏移を研究した。研磨したCdドープp-型InP(001)の試料面を500eVのAr(+)イオンによりスパッタリングし、次いで350度Cで焼鈍を行い、炭素と酸素を含有しない、鮮明な(2×4)LEED(低速電子回折)パターンを示す試料面を得た。In-4d準位の表面コア準位偏移を種々の検出角θ(15度から84度)で測定した。種々の検出角に対する(2×4)清浄面のIn-4dスペクトルを図に示した。スペクトルは4成分(S1、S2、S3およびB)に分割し、種々のθに対する4成分の強度比の変化を各成分ごとに論じた。成分S1の強度は角度の増加に伴い指数関数的に増大すること、成分Bの強度は角度の増加にしたがって大きく低下することが分かった。成分S2とS3の強度は角度の増加に伴い初めは増大するがその後は低下した。