ISSN:
1013-9826
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
The large-sized sapphire (Ø225×205 mm, 27.5 kg) was grown successfully by SAPMACmethod (sapphire growth technique with micro-pulling and shoulder-expanding at cooled center).The surface quality of the specimens was characterized by micro-Raman spectroscopy, and doublecrystal X-ray diffractometry (DCD) was utilized to investigate its crystalline perfection. Themeasurement of rocking curves was performed on various specimens from different region of largesapphire boule. The experimental results showed that CMP (chemo-mechanical polishing) withsubsequent suitable chemically etching can develop the best-quality sapphire crystal surface and thevalues of FWHM obtained by conventional DCD were in the range from 27” to 58”. The infraredspectral transmission (2.0-4.5 5m) of sapphire crystal exceeded 82%. It is confirmed of SAPMACgrowth method characteristics with in-situ annealing, small temperature gradient and low residualstress level by numerical simulation analysis
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/55/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.353-358.1521.pdf
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