Cupric oxide inclusions in cuprous oxide crystals grown by the floating zone method

Laszlo Frazer; Kelvin B Chang; Kenneth R Poeppelmeier; John B Ketterson

doi:10.1088/1468-6996/16/3/034901

Cupric oxide inclusions in cuprous oxide crystals grown by the floating zone method

Sci Technol Adv Mater. 2015 May 8;16(3):034901. doi: 10.1088/1468-6996/16/3/034901. eCollection 2015 Jun.

Authors

Laszlo Frazer¹, Kelvin B Chang², Kenneth R Poeppelmeier³, John B Ketterson⁴

Affiliations

¹ Department of Chemistry, Temple University, 1901 N. 13th Street, Philadelphia, PA 19122, USA.
² Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3112, USA.
³ Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3112, USA; Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA.
⁴ Department of Chemistry, Temple University, 1901 N. 13th Street, Philadelphia, PA 19122, USA; Department of Electrical Engineering and Computer Science, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3112, USA.

Abstract

Phase-pure cuprous oxide (Cu₂O) crystals are difficult to grow since cupric oxide can form within the crystal as the crystal is cooled to ambient conditions. Vacancies are the solute which causes precipitation of macroscopic defects. Therefore, even when a mostly phase-pure single crystal is used as a feed rod, cupric oxide inclusions persist in the recrystallized solid. Control of the thermal profile during crystal growth, however, can improve phase-purity; a slow counter-rotation rate of the feed and seed rods results in fewer inclusions. Cupric oxide can be removed by annealing, which produces a factor of 540 ± 70 increase in phase-purity.

Keywords: cuprous oxide; floating zone; inclusions; oxides.