@article {Bregman19892628,
	title = {Substrate effect on the electrical properties of a-Si:H thin films and its modification by diffusion-blocking interlayers},
	journal = {Journal of Vacuum Science and Technology A: Vacuum, Surfaces and Films},
	volume = {7},
	number = {4},
	year = {1989},
	note = {<p>cited By 1</p>
},
	pages = {2628-2631},
	abstract = {<p>Electrical dark conductivity (σd) and surface composition of undoped and doped a-Si:H thin films have been investigated, using coplanar I-V as a function of temperature and Auger electron spectroscopy (AES). The films were prepared by rf glow discharge deposition on standard soda-lime glass and on alkali-free glass substrates. Comparing these two sets of substrates for undoped films, we find that σd of the films deposited on soda-lime glass substrates at room temperature is higher by more than two orders of magnitude, their activation energy is lower by about a factor of 3, and their photosensitivity (σph/σd) is lower by two orders of magnitude than that of the films deposited on alkali-free glass substrates. We suggest that Na ions, leached from the glass into the a-Si:H overlayer play a significant role in determining the film conductivity by creating electrically active donorlike states. This conclusion is supported by similar measurements on p- and n-type a-Si:H films on the same substrates and by AES results. Films of a-Si:H, grown on thin a-Si:C:H interlayers on soda-lime glass, showed very low Na concentrations and low dark conductivities as found by AES and electrical measurements, respectively. The role of the a-Si:C:H interlayers as diffusion barriers is discussed. {\textcopyright} 1989, American Vacuum Society. All rights reserved.</p>
},
	doi = {10.1116/1.575808},
	url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-80055052298\&partnerID=40\&md5=33d14f72a46491a6b0eea033ecc7c72c},
	author = {Bregman, J.a , Gordon, J.a , Shapira, Y.a , Fortunato, E.b , Martins, R.b , Guimaraes, L.b}
}
