Growth of Large-Diameter GaAs Single Crystals

The directional solidification in a horizontal boat used for many years to grow doped GaAs single crystals lost its importance because of the D-shaped cross section, which is inappropriate for device manufacturing. 

The Bridgman method first applied by Beljackaja and Grishina for III-V compounds [13] was rediscovered by Gault et al. [14] in 1986 and Hoshikawa et al. [15] in 1989. As the nonlinearities of the temperature field in the grown crystals are significantly lower than in the LEG method, low-dislocation-density crystals can be grown by this method. 

The development of the diameter of GaAs single crystals over time is represented in Fig. 9.4. 

Finally, as shown in Fig. 9.5(b), the deviation from stoichiometry can be influenced to a Umited extent by boule aimeating after crystal growth under 

3 Growth of Large-Diameter CaAs Single Crystals 239 

---