P A P E R    T I T L E
Properties of 6-inch Semi-insulating GaAs Substrates Manufactured by Vertical Boat Method
A U T H O R  /  C R E D I T S
by Tomohiro Kawase, Hiroaki Yoshida, Takashi Sakurada, Yoshiaki Hagi, Kazuya Kaminaka, Hideki Miyajima, Shigeru Kawarabayashi, Nobuo Toyoda, Makoto Kiyama, Shinichi Sawada and Ryusuke Nakai

Sumitomo Electric Industries, Ltd.
1-1-1, Koya-kita, Itami, Hyogo, 664-0016 Japan
Phone: +81-727-72-4581, Fax: +81-727-72-2440, e-mail: kawase@asd.sei.co.jp

Cost reduction is the top priority of device manufacturers to overcome keen competition and obtain larger market share. The 6-inch process is the key technology in achieving the cost reduction goal.

However, the larger temperature difference in a 6-inch wafer in comparison to a 4-inch wafer increases the possibility of slip-dislocation generation and wafer breakage during high temperature processes. This prevents device manufacturers from succeeding with the 6-inch process. Enlarging the diameter from 4 inches to 6 inches also causes the increase of dislocation density and residual strain as well as difficulty in obtaining good reproducibility of the crystals.

Growth of 6-inch GaAs single crystals by LEC[1], VCZ[2] and VGF[3] methods have been reported and the manufacturing efforts continue. The 6-inch wafer production by the LEC method was reported at the GaAs MANTECH Conference in 1998[4].

We have successfully developed the Vertical Boat (VB) method for mass production of GaAs substrates with low dislocation density and low residual strain. This is the first report on the properties of 6-inch semi-insulating GaAs substrates manufactured by the VB method.