Semiconductor laser manufacturing method
View Patent ↗A method for manufacturing a semiconductor laser. As a preparative step for coating an end face of a resonator with a dielectric film, a cleavage plane of a semiconductor laminated structure that is to be the end face is subjected to a plasma cleaning to prevent a conductive film, which absorbs laser light, from attaching to the cleavage plane. During the plasma cleaning, a first process gas containing argon gas and nitrogen gas is introduced into a vacuumed ECR sputtering apparatus. After the cleavage plane is exposed to the first process gas in the plasma state for a certain time period without application of a voltage, a second process gas containing argon gas and oxygen gas is introduced, and the cleavage plane is exposed to the second process gas in the plasma state while a voltage is applied to the silicon target.
1. A semiconductor laser manufacturing method for manufacturing a semiconductor laser by cleaning a cleavage plane of a semiconductor laminated structure by a plasma cleaning using a sputtering apparatus, the cleavage plane being to be an end face of a resonator, the method comprising:
a first step of placing the semiconductor laminated structure with the cleavage plane in the sputtering apparatus;
a second step of introducing a process gas containing a reactive gas and an inert gas into the sputtering apparatus, and then putting the process gas into a plasma state; and
a third step of exposing a target material and the cleavage plane to the process gas in the plasma state while no voltage is applied to the target material, causing a reaction of the target material and the reactive gas to form a compound that reflects light of a predetermined wavelength so that a film of the compound is formed on the cleavage plane.
2. The semiconductor laser manufacturing method of claim 1 , further comprising:
a fourth step of, after the third step, putting a second process gas containing an oxygen gas and an inert gas into a plasma state; and
a fifth step of exposing the target material and the cleavage plane to the second process gas in the plasma state while a voltage is applied to the target material, causing a reaction of the target material and the oxygen gas to form an oxide so that a film of the oxide is formed on the cleavage plane.
3. The semiconductor laser manufacturing method of claim 1 , wherein
the reactive gas is a non-oxidation gas.
4. The semiconductor laser manufacturing method of claim 1 , wherein
the reactive gas is a gas containing either nitrogen or hydrogen.
5. The semiconductor laser manufacturing method of claim 1 , wherein
the compound is insulative.
6. The semiconductor laser manufacturing method of claim 1 , wherein
the predetermined wavelength is a semiconductor laser emission wavelength.
7. The semiconductor laser manufacturing method of claim 1 , wherein
the target material is selected from the group consisting of silicon, aluminum, titanium zirconium, hafnium, zinc, cerium, tantalum, niobium, and strontium.
8. The semiconductor laser manufacturing method of claim 1 , wherein
a partial pressure ratio of the reactive gas to the inert gas in the process gas is 5% to 100%.
9. The semiconductor laser manufacturing method of claim 1 , wherein
a partial pressure ratio of the reactive gas to the inert gas in the process gas is 10% to 30%.
10. The semiconductor laser manufacturing method of claim 1 , wherein
the sputtering apparatus is an ECR sputtering apparatus.