Nitride semiconductor laser element
AssigneesUshio Denki Kabushiki Kaisha, Osaka University
InventorsToshihiko FUKAMACHI, Masahiro UEMUKAI, Ryuji KATAYAMA, Tomoyuki TANIKAWA
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Abstract
In a distributed feedback semiconductor laser element, a multi-layered structure includes a GaN substrate, an n-type semiconductor layer, an active layer, and a p-type semiconductor layer, and a ridge waveguide is formed. A first diffraction grating is formed adjacent to and on both sides of the ridge waveguide. A depth d of a groove of the first diffraction grating is included in the range of 50 nm d≤200 nm, and a duty ratio duty is included in the range of an inequality (1) using constants a, b, c, and n defined for the order of the diffracted light. - d - c a n + b ≦ duty ≦ d - c a n + b ( 1 )
Claims14
A distributed feedback semiconductor laser element, the semiconductor laser element comprising:
- a multi-layered structure including a GaN substrate, a first conductivity-type semiconductor layer, a light emitting layer, and a second conductivity-type semiconductor layer, in which a ridge waveguide is formed;
- and
- a first diffraction grating formed adjacent to and on both sides of the ridge waveguide, wherein
- a groove depth d of the first diffraction grating is included in a range of 50 nm≤d≤200 nm, and a duty ratio duty is included in a range of an inequality (1):
- -
- d
- -
- c
- a
- n
- +
- b
- ≦
- duty
- ≦
- d
- -
- c
- a
- n
- +
- b
- (
- 1
- )
- using constants a, b, c, and n defined for an order of diffracted light.
A method of manufacturing a distributed feedback semiconductor laser element, the method comprising the steps of:
- forming a multi-layered structure including a GaN substrate, a first conductivity-type semiconductor layer, a light emitting layer, and a second conductivity-type semiconductor layer;
- forming a ridge stripe structure in the multi-layered structure;
- forming a first diffraction grating adjacent to the ridge stripe structure;
- and
- forming an insulating film inside a groove of the first diffraction grating, wherein
- a groove depth d of the first diffraction grating is included in a range of 54.9 nm≤d≤200 nm, and a duty ratio duty is included in a range of an inequality (1):
- -
- d
- -
- c
- a
- n
- +
- b
- ≦
- duty
- ≦
- d
- -
- c
- a
- n
- +
- b
- (
- 1
- )
- using constants a, b, c, and n defined for an order of diffracted light.
Dependencies are inferred from the claim text.