| 摘要 |
<p>After a semiconductor layer group constituting a DFB laser is formed in a DFB laser area (51), the patterning of the semiconductor layer group is performed by using a mask having a width W<SUB>1</SUB>. Then, a semiconductor layer constituting an EA modulator is formed in an EA modulator area (52). Thereafter, a SiO<SUB>2</SUB> film (11) is formed as a mask. The width W<SUB>2</SUB> of the SiO<SUB>2</SUB> film (11) in the DFB laser area (51) is larger than the width W<SUB>1</SUB> in the EA modulator area (52).</p> |
