open access

https://hdl.handle.net/2115/73137

Growth of Li2B4O7 Single Crystals by a Pulling-Down Method

日本語

Pulling-down method

1997-07-01

日本セラミックス協会

日本セラミックス協会学術論文誌

105(1223)

616-619

Bubble-free, transparent Li2B4O7 single crystals were grown by a newly developed pulling-down method. The use of a two-zone vertical furnace with a Pt-crucible realized a relatively steep temperature gradient of about 50°C/cm around the growth interface and a moderate gradient of about 13°C/cm below the interface, contributing to prevent grown crystals from cracking. Even at a pulling-down rate of 0.75mm/h, which is higher than that in the Czochralski growth, the formation of bubbles was effectively suppressed at a rotation rate of 25rpm. Any crystals grown along [110] direction involved no low-angle grain boundaries, but twinning was occasionally recognized. The dislocation density in the initial part of the crystal growth was found to be about 5×103/cm2 from an etch pit pattern, while X-ray topography of a vertical cross section revealed that the number of dislocation lines decreased as the growth proceeded.

学術雑誌論文

Version of Record

Creative Commons Attribution-NoDerivatives 4.0 International

0914-5400

1882-1022

AN10040326