| 摘要 |
<p>In a method for producing a diffraction grating having a minute pitch in devices such as semiconductor lasers and filters, the steps of forming a diffraction grating having a first pitch, coating the diffraction grating with material different from that of the diffraction grating, and forming a diffraction grating having a second pitch different from the first pitch by an etching process are performed. This etching process includes a step of simultaneously etching the different coating material and the diffraction grating having the first pitch. The second pitch is, for example, half of the first pitch. <IMAGE></p> |
