FORMING METHODS OF GRATING HAVING CONTINUOUSLY SHIFTING PITCH AND LASER DIODES EMITTING BEAMS OF DIFFERENT WAVELENGTH USING THE GRATING

摘要

PURPOSE: A method of forming a grating which has a continuously shifting pitch and a method of forming laser diodes each of which emits a beam of different wavelength are provided to reduce production cost, to enable mass production, and to easily adjust the pitch of the grating. CONSTITUTION: A wafer(1) is coated with a photoresist layer(2), and a mirror(5) is arranged by the side of the wafer(1). In addition, a light source(3) to emit spherical light is positioned apart from the wafer(1) and the mirror(5). The distance between the wafer(1) and the light source(3), and an angle between the wafer(1) and the mirror(5) are all adjusted to correspond to a pitch of a grating to be formed on the wafer(1). The photoresist layer(2) is then exposed to interferential light between direct light(4) of a light source(3) and reflected light(6) of the mirror(5). After the exposed photoresist layer(2) is developed, the wafer(1) is etched to form the grating having the continuously shifting pitch. In this manner, laser diodes each of which can emit a beam of different wavelength are formed on the single wafer(1).