Semiconductor laser element

Patent metadata

Field	Value
Publication number	US-2022013987-A1
Application number	US-202117487405-A
Country	US
Kind code	A1
Filing date	Sep 28, 2021
Priority date	Apr 2, 2019
Publication date	Jan 13, 2022
Grant date	—

Abstract

A semiconductor laser element includes: a first conductivity-type cladding layer; a first guide layer disposed above the first conductivity-type cladding layer; an active layer disposed above the first guide layer; and a second conductivity-type cladding layer disposed above the active layer. A window region is formed in a region of the active layer including part of at least one of the front-side end face or the rear-side end face, the first conductivity-type cladding layer consists of (AlxGa1-x)0.5In0.5P, the first guide layer consists of (AlyGa1-y)0.5In0.5P, and the second conductivity-type cladding layer consists of (AlzGa1-z)0.5In0.5P, where x, y, and z each denote an Al composition ratio, 0<x−y<z−y is satisfied, and D/L>0.03 is satisfied, where L denotes a length of the resonator and D denotes a length of the window region in the first direction.

First claim

1 . A semiconductor laser element including a resonator in which laser light resonates in a first direction between a front-side end face and a rear-side end face, the semiconductor laser element comprising:
a first conductivity-type cladding layer disposed above a first conductivity-type semiconductor substrate; a first guide layer disposed above the first conductivity-type cladding layer; an active layer disposed above the first guide layer; and a second conductivity-type cladding layer disposed above the active layer, wherein a window region is formed in a region of the active layer including part of at least one of the front-side end face or the rear-side end face, the first conductivity-type cladding layer consists of (Al x Ga 1-x ) 0.5 In 0.5 P, where x denotes an Al composition ratio, the first guide layer consists of (Al y Ga 1-y ) 0.5 In 0.5 P, where y denotes an Al composition ratio, the second conductivity-type cladding layer consists of (Al z Ga 1-z ) 0.5 In 0.5 P, where z denotes an Al composition ratio, 0<x−y<z−y is satisfied, and D/L>0.03 is satisfied, where L denotes a length of the resonator and D denotes a length of the window region in the first direction.

2 . A semiconductor laser element including a resonator in which laser light resonates in a first direction between a front-side end face and a rear-side end face, the semiconductor laser element comprising:
a first conductivity-type cladding layer disposed above a first conductivity-type semiconductor substrate; a first guide layer disposed above the first conductivity-type cladding layer; an active layer disposed above the first guide layer; and a second conductivity-type cladding layer disposed above the active layer, wherein a window region is formed in a region of the active layer including part of at least one of a front-side end face or a rear-side end face, the first conductivity-type cladding layer consists of (Al x Ga 1-x ) 0.5 In 0.5 P, where x denotes an Al composition ratio, the first guide layer consists of (Al y Ga 1-y ) 0.5 In 0.5 P, where y denotes an Al composition ratio, the second conductivity-type cladding layer consists of (Al z Ga 1-z ) 0.5 In 0.5 P, where z denotes an Al composition ratio, 0<x−y<z−y is satisfied, the window region includes a stable window region having an energy band gap that is at least 30 meV greater than an energy band gap of a region of the active layer other than the window region, and D1/L>0.01 is satisfied, where L denotes a length of the resonator and D1 denotes a length of the window region in the first direction.

3 . The semiconductor laser element according to claim 1 , wherein
the second conductivity-type cladding layer includes a lower layer and an upper layer disposed in stated order from an active layer side, the lower layer consists of (Al w Ga 1-w ) 0.5 In 0.5 P, where w denotes an Al composition ratio w, and x−y<w−x and w<z are satisfied.

4 . The semiconductor laser element according to claim 2 , wherein
the second conductivity-type cladding layer includes a lower layer and an upper layer disposed in stated order from an active layer side, the lower layer consists of (Al w Ga 1-w ) 0.5 In 0.5 P, where w denotes an Al composition ratio w, and x−y<w−x and w<z are satisfied.

5 . A semiconductor laser element including a resonator in which laser light resonates in a first direction between a front-side end face and a rear-side end face, the semiconductor laser element comprising:
a first conductivity-type cladding layer disposed above a first conductivity-type semiconductor substrate; a first guide layer disposed above the first conductivity-type cladding layer; an active layer disposed above the first guide layer; and a second conductivity-type cladding layer disposed above the active layer, wherein a window region is formed in a region of the active layer including part of at least one of a front-side end face or a rear-side end face, a refractive index of the first guide layer is greater than a refractive index of the first conductivity-type cladding layer, and a difference between the refractive index of the first guide layer and the refractive index of the first conductivity-type cladding layer is less than a difference between the refractive index of the first conductivity-type cladding layer and a refractive index of the second conductivity-type cladding layer, and D/L>0.03 is satisfied, where L denotes a length of the resonator and D denotes a length of the window region in the first direction.

6 . A semiconductor laser element including a resonator in which laser light resonates in a first direction between a front-side end face and a rear-side end face, the semiconductor laser element comprising:
a first conductivity-type cladding layer disposed above a first conductivity-type semiconductor substrate; a first guide layer disposed above the first conductivity-type cladding layer; an active layer disposed above the first guide layer; and a second conductivity-type cladding layer disposed above the active layer, wherein a window region is formed in a region of the active layer including part of at least one of a front-side end face or a rear-side end face, a refractive index of the first guide layer is greater than a refractive index of the first conductivity-type cladding layer, and a difference between the refractive index of the first guide layer and the refractive index of the first conductivity-type cladding layer is less than a difference between the refractive index of the first conductivity-type cladding layer and a refractive index of the second conductivity-type cladding layer, the window region includes a stable window region having an energy band gap that is at least 30 meV greater than an energy band gap of a region of the active layer other than the window region, and D1/L>0.01 is satisfied, where L denotes a length of the resonator and D1 denotes a length of the window region in the first direction.

7 . The semiconductor laser element according to claim 5 , wherein
the second conductivity-type cladding layer includes a lower layer and an upper layer disposed in stated order from an active layer side, and the difference between the refractive index of the first guide layer and the refractive index of the first conductivity-type cladding layer is less than a difference between the first conductivity-type cladding layer a refractive index of the lower layer, and the refractive index of the lower layer is greater than the refractive index of the second conductivity-type cladding layer.

8 . The semiconductor laser element according to claim 6 , wherein
the second conductivity-type cladding layer includes a lower layer and an upper layer disposed in stated order from an active layer side, and the difference between the refractive index of the first guide layer and the refractive index of the first conductivity-type cladding layer is less than a difference between the first conductivity-type cladding layer a refractive index of the lower layer, and the refractive index of the lower layer is greater than the refractive index of the second conductivity-type cladding layer.

9 . The semiconductor laser element according to claim 3 , wherein
the second conductivity-type cladding layer includes an upper face that is an upper end face, and a ridge that protrudes upward from the upper face and extends in the first direction.

10 . The semiconductor laser element according to claim 9 , wherein
at the upper face, the lower layer is exposed from the upper layer.

11 . The semiconductor laser element according to claim 10 , further comprising:
a dielectric film disposed on the upper face, wherei

Assignees

• Nuvoton Technology Corp Japan

Inventors

• Yamada Kazuya
• Nakatani Tougo
• Nagai Hiroki
• Hata Masayuki

Classifications

• H01S5/3202

  grown on specifically orientated substrates, or using orientation dependent growth · CPC title

• H01S5/162

  with window regions made by diffusion or disordening of the active layer · CPC title

• H01S2301/176

  Specific passivation layers on surfaces other than the emission facet · CPC title

• H01S5/1039

  Details on the cavity length · CPC title

• H01S2301/18

  Semiconductor lasers with special structural design for influencing the near- or far-field · CPC title