Title :
Infrared and laser spectroscopic characterization of aluminium defects in cultured quartz
Author :
Lipson, Herbert G.
Author_Institution :
Rome Air Dev. Center, Hanscom AFB, MA, USA
Abstract :
Optical absorption at He-Ne and argon laser frequencies has been used to map the distribution of aluminium-hole centres, Al-H/sup +/, in irradiated and vacuum swept quartz. The absorption band associated with Al-h/sup +/ has a strong peak centered at 435 nm and a weaker one at 633 nm. Argon laser lines at 488 and 514.5 nm are close to the wavelength of the stronger peak, while the He-Ne line at 632.8 nm is nearly coincident with that of the weaker peak. Large variations in Al-h/sup +/ absorption for irradiated and vacuum swept crystals correspond to visually observed changes in coloration. The laser method is sensitive and nondestructive, and gives a quantitative measurement adaptable to computerized scanning and recording of data. Measurements of both Al-h/sup +/ and infrared-active aluminium hydroxide centres, Al-OH/sup -/, are used to evaluate the distribution of aluminium-associated defect centres and determine aluminium variations over an entire crystal.<>
Keywords :
OH/sup -/-centres; V-centres; defect electron energy states; impurity and defect absorption spectra of inorganic solids; infrared spectra of inorganic solids; quartz; radiation effects; visible spectra of inorganic solids; 435 nm; 488 nm; 574.5 nm; 632.8 nm; 633 nm; Al defects; Ar laser lines; He-Ne laser frequency; SiO/sub 2/; SiO/sub 2/:Al; absorption band; coloration; computerised data recording; computerized scanning; cultured quartz; defect centres; hole centers; infrared absorption; irradiated quartz; laser spectroscopic characterization; optical absorption; vacuum swept crystals; vacuum swept quartz; Aluminum; Argon; Crystals; Electromagnetic wave absorption; Hydrogen; Impurities; Infrared spectra; Laser beams; Paramagnetic resonance; Spectroscopy;
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on
