| 摘要 |
PROBLEM TO BE SOLVED: To provide a gallium arsenide single crystal having a low optical absorption coefficient.SOLUTION: In the gallium arsenide single crystal, a charge carrier concentration is at least 1x10cm, and maximum 1x10cm, and an optical absorption coefficient is maximum 2.5 cmwith a wave length of 1000 nm, maximum 1.8 cmwith a wave length of 1100 nm, and maximum 1.0 cmwith a wave length of 1200 nm. An EL2 concentration is less than 1x10cm, a boron concentration is at least 5x10cm, and an etch pit density is no more than 1500 cmin a cross section vertical to a crystal axis. The crystal is characterized by specifically combining low dislocation density, high conductivity and excellent low optical absorption properties especially in a near infrared ray region. |
