Swelling and optical properties of Si3N4 films irradiated in the electronic regime

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS

卷:267

Article; Proceedings Paper

Canut, B.¹  Ayari, A.²  Dupuis, J.¹  Lemiti, M.¹  Fave, A.¹  Ramos, S.³ 

[1] Univ Lyon 1, Inst Nanotechnol Lyon, CNRS, UMR 5270, F-69622 Villeurbanne, France

[2] Univ Sherbrooke, Ctr Rech Nanofabricat & Nanocaracterisat, Sherbrooke, PQ J1K 2R1, Canada

[3] Univ Lyon 1, Lab Phys Mat Condensee & Nanostruct, CNRS, UMR 5586, F-69622 Villeurbanne, France

关键词: Irradiation;    Silicon nitride;    Swelling;    Optical properties;   

DOI  :  10.1016/j.nimb.2009.02.023

来源: Elsevier

【 摘 要 】

Silicon nitride layers of 140 nm thickness were deposited on silicon wafers by low pressure chemical vapour deposition (LPCVD) and irradiated at GANIL with Pb ions of 110 MeV up to a maximum fluence of 4 x 10(13) cm(-2). As shown in a previous work these irradiation conditions, characterized by a predominant electronic slowing-down (S-e = 19.3 keV nm(-1)), lead to damage creation and formation of etchable tracks in Si3N4. In the present Study we investigated other radiation-induced effects like out of plane swelling and refractive index decrease. From profilometry, step heights as large as 50 rim were measured for samples irradiated at the highest fluences (>10(13) cm(-2)). From optical spectroscopy, the minimum reflectivity of the target is shifted towards the high wavelengths at increasing fluences. These results evidence a concomitant decrease of density and refractive index in irradiated Si3N4. Additional measurements, performed by ellipsometry, are in full agreement with this interpretation. (C) 2009 Elsevier B.V. All rights reserved.

【 授权许可】

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