Hydrogen kinetics in a-Si:H and a-SiC:H thin films investigated by real-time ERD

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

卷:349

Article

Halindintwali, S.¹  Khoele, J.¹  Nemroaui, O.²  Comrie, C. M.^3,4  Theron, C. C.⁵ 

[1] Univ Western Cape, Dept Phys, ZA-7535 Bellville, South Africa

[2] Cape Peninsula Univ Technol, Dept Mechatron, ZA-7535 Bellville, South Africa

[3] Univ Cape Town, Dept Phys, ZA-7700 Rondebosch, South Africa

[4] iThemba LABS, Mat Res Dept, ZA-7129 Somerset West, South Africa

[5] Univ Pretoria, Dept Phys, ZA-0028 Hatfield, South Africa

关键词: Kinetic property;    Activation energy;    Stoichiometric;    Depth profile;    Arrhenius plot;   

DOI  :  10.1016/j.nimb.2015.02.040

来源: Elsevier

【 摘 要 】

Hydrogen effusion from hydrogenated amorphous silicon (a-Si:H) and amorphous silicon carbide (a-Si1-xCx:H) thin films during a temperature ramp between RT and 600 degrees C was studied by in situ real-time elastic recoil detection analysis. Point to point contour maps show the hydrogen depth profile and its evolution with the ramped temperature. This paper proposes a diffusion limited evolution model to study H kinetic properties from total retained H contents recorded in a single ramp. In a compact a-Si:H layer where H predominantly effuses at high temperatures between 500 and 600 degrees C, an activation energy value of similar to 1.50 eV and a diffusion pre-factor of 0.41 x 10(-4) cm(2)/s were obtained. Applied to an non-stoichiometric a-Si1-xCx:H film in the same range of temperature, the model led to reduced values of activation energy and diffusion prefactor of similar to 033 eV and 0.59 x 10(-11) cm(2)/s, respectively. (C) 2015 Elsevier B.V. All rights reserved.

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