back to S1S home

Sunday, May 3, 2015

#325 Charge carrier scattering depends on crystal structure

For all practical purposes defects scattering (see #324) comes to play in the major way only in the single crystal semiconductors, i.e. in those featuring a long-range periodic order of the crystal lattice throughout the entire piece of material.



In the polycrystalline version of the same semiconductor, e.g. silicon, Si, where a long-range periodic order is maintained only within limited in volume grains, defects related to the grain boundaries will inherently cause major scattering of the moving carriers and thus, decrease significantly charge carrier mobility.



Finally, the same silicon comes also in the non-crystalline (amorphous) thin-film version where there is no long-range periodic order. At the very high density of point defects in amorphous thin-film silicon the carrier mobility decreases by up to three orders of magnitude as compared to single-crystal bulk silicon. That is not to say that becasue of the dismal mobility charactersitics amporphous semiconductors are not useful in practical device applications. Just consider a broad field of thin-film transistor (TFT) technology....


Posted by Jerzy Ruzyllo at 08:55 PM | Semiconductors | Link is the personal blog of Jerzy Ruzyllo. With over 35 years of experience in academic research and teaching in the area of semiconductor engineering (currently holding position of a Distinguished Professor of Electrical Engineering and Professor of Materials Science and Engineering at Penn State University), he has a unique perspective on the developments in this progress driving technical domain and enjoys blogging about it.

With over 2000 terms defined and explained, Semiconductor Glossary is the most complete reference in the field of semiconductors on the market today.

‹‹ January 2019 ››
W Mo Tu We Th Fr Sa Su
1 1 2 3 4 5 6
2 7 8 9 10 11 12 13
3 14 15 16 17 18 19 20
4 21 22 23 24 25 26 27
5 28 29 30 31      

Copyright © 2019 J. Ruzyllo. All rights reserved.