SEMICONDUCTOR LASER AND MODULATOR

摘要

PURPOSE: To greatly reduce chirping by forming a window region having a larger width than a modulator located laterally on an integrated laser/modulator and by controlling the length of the window region. CONSTITUTION: An integrated laser/modulator comprises a laser 1, a wavelength selective grating 2, a modulator 3 and a separating means or a window region 4A. A V-shaped groove 9 is disposed in a place located at an appropriate distance from a modulator 8A forming the window region 4A. Disposition of the V-shaped groove 9 can be controlled with accuracy of±1 micron by a method of optical lithography. By this accurate disposition using the method of optical lithography, the V-shaped groove 9 can be positioned at a portion corresponding to the outer side of the integrated laser/modulator and the window region. By controlling the disposition of the groove 9, the length of the window region can also be controlled accurately. Thereby the effect of chirping can be reduced.