Electronic states of phosphorus in diamond

Citation
E. Gheeraert et al., Electronic states of phosphorus in diamond, DIAM RELAT, 9(3-6), 2000, pp. 948-951
Citations number
11
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science","Material Science & Engineering
Journal title
DIAMOND AND RELATED MATERIALS
ISSN journal
0925-9635 → ACNP
Volume
9
Issue
3-6
Year of publication
2000
Pages
948 - 951
Database
ISI
SICI code
0925-9635(200004/05)9:3-6<948:ESOPID>2.0.ZU;2-U
Abstract
A set of rt-type diamond thin films was investigated by infra-red absorptio n spectroscopy. The films were grown by CVD on {111} synthetic diamond, and phosphorus-doped using [P]/[C] = 100-5000 ppm of phosphine in the gas phas e during growth. The phosphorus concentration in the films ranged from arou nd 5 x 10(17) cm(-3) to 2 x 10(19) cm(-3). A continuum of absorption, attri buted to the photoionisation of neutral phosphorus, is observed together wi th two peaks at 523 and 562 meV attributed to electronic transitions from t he ground level of phosphorus to its first and second excited states. The e nergy difference between these two peaks is in agreement with the effective mass approximation applied for the rt-type diamond, suggesting that phosph orus behaves like a shallow level centre. Assuming that phosphorus is a per fect shallow level, the optical ionisation energy of 600 meV (+/- 20 meV) i s deduced, consistent with the thermal activation energy. (C) 2000 Elsevier Science S.A. All rights reserved.