Early stage of V deposition on Si(100) 2 x 1

Abstract

In relation to room temperature alloyed interface formation, the early process of vanadium overlayer formation on Si(100) 2 x 1 surface was investigated by photoemission spectroscopy using synchrotron radiation. The photoelectron measurements were performed at Beamline-2 (BL-2) of Synchrotron Orbital Radiation Ring (SOR-RING) on the clean Si surface with V deposition in various coverage, and the photoemission spectra of the Si(2p) and the Valence Band Energy Distribution Curves (VB-EDCs) were measured at photon energies 125 eV and 50 eV, respectively. In the former measurement, with increasing V coverage, the peak position of the Si(2p) shifted toward lower binding energy and the full width at half maximum of Si(2p) increased gradually from the beginning of V deposition. Also, in the latter measurement, the signal peaked at a binding energy of about 1 eV varied with the V coverage and was different from that due to V(3d) electron. Both results indicate that the deposited V atoms make chemical bond with substrate Si atoms to form V-Si reacted product from the beginning of V deposition.

室温合金界面の形成に関連して、Si(100)2×1面に於けるバナジウム被覆層形成の初期挙動をシンクロトロン発射による光電子放出分光法により調べた。光電子測定は、Vが各種の被覆割合で析出したSiの清浄面について、シンクロトロン軌道放射リング(SOR-RING)のビームライン2(BL-2)で行い、Si(2p)の光電子放出スペクトルと価電子帯エネルギー分布曲線(VB-EDCs)を、各々、光量子エネルギー125eVと50eVで測定した。前者の測定では、V被覆割合の増加に伴い、Si(2p)のピーク位置が低結合エネルギー側に移動し、その半値全幅はV析出の初期から徐々に増大した。また、後者の測定では、結合エネルギー1eVに於けるピークの信号はV被覆割合で変わり、V(3d)電子に依る信号とは異なっていた。両方の結果は、析出V原子が基材Siと化学結合し、V析出の初期からV-Si反応生成物を形成していたことを示す。