Quantum cascade laser manufacturing method

摘要

A quantum cascade laser manufacturing method includes: a step of pressing a mother stamper against a resin film having flexibility to make a resin stamper 201 having a second groove pattern P2; a step of making a wafer with an active layer formed on a semiconductor substrate; a step of forming a resist film 304 on a surface on the active layer side of the wafer; a step of pressing the resin stamper against the resist film 304 by air pressure to form a third groove pattern P3 on the resist film 304; and a step of etching the wafer with the resist film 304 serving as a mask to form a diffraction grating on a surface of the wafer.

主权项

1. A quantum cascade laser manufacturing method comprising:
a first step of preparing a mother stamper with a predetermined first groove pattern formed on a surface of a substrate; a second step of pressing the mother stamper against a heated resin film having flexibility and maintaining pressure of the mother stamper while the resin film cures to transfer the first groove pattern to the resin film and making a resin stamper with a second groove pattern formed on the resin film, the second groove pattern having an inverted asperity of the first groove pattern; a third step of making a wafer, which includes a semiconductor substrate and an active layer formed on the substrate, the active layer having a cascade structure, the cascade structure including a plurality of quantum well light emitting layers and a plurality of injection layers, the plurality of quantum well light emitting layers and the plurality of injection layers being stacked alternately; a fourth step of forming an intermediate film on a surface on the active layer side of the wafer; a fifth step of forming a resist film on a surface of the intermediate film; a sixth step of pressing the resin stamper against the resist film by air pressure to transfer the second groove pattern to the resist film and forming on the resist film a third groove pattern having an inverted asperity of the second groove pattern, wherein the sixth step comprises:
pressing the resin stamper down onto the resist film at a first air pressure while heating the resist film at a temperature lower than that of the second step,then pressing the resin stamper down onto the resist film at a second air pressure higher than the first air pressure while continuing to heat the resist film at the temperature lower than that of the second step, andthen, after a predetermined time has passed since applying the second air pressure, irradiating the resist film with ultraviolet light; a seventh step of etching the intermediate film with the resist film serving as a mask; an eighth step of etching the wafer with the etched intermediate film in the seventh step serving as a mask to form a phase shifting diffraction grating on a surface of the wafer; and a ninth step of removing the etched intermediate film after the eighth step, wherein the intermediate film is a SiN film or a SiO2 film.