Semiconductor light-emitting device and manufacturing method for the same

Patent metadata

Field	Value
Publication number	US-9991669-B2
Application number	US-201715656096-A
Country	US
Kind code	B2
Filing date	Jul 21, 2017
Priority date	Jul 25, 2016
Publication date	Jun 5, 2018
Grant date	Jun 5, 2018

Abstract

The embodiment relates to a semiconductor light-emitting device comprising a semiconductor substrate, a first cladding layer, an active layer, a second cladding layer, a contact layer, and a phase modulation layer located between the first cladding and active layers or between the active and second cladding layers. The phase modulation layer comprises a basic layer and plural first modified refractive index regions different from the basic layer in a refractive index. In a virtual square lattice set on the phase modulation layer such that the modified refractive index region is allocated in each of unit constituent regions constituting square lattices, the modified refractive index region is arranged to allow its gravity center position to be separated from the lattice point of the corresponding unit constituent region, and to have a rotation angle about the lattice point according a desired optical image.

First claim

What is claimed is:

1. A semiconductor light-emitting device configured to output an optical image of an arbitrary shape in one of a normal direction of a main surface of a semiconductor substrate, an inclined direction having a predetermined inclination and having a divergence angle with respect to the normal direction, and both the normal direction and the inclined direction, the semiconductor light-emitting device comprising:
the semiconductor substrate;
a first cladding layer provided on the semiconductor substrate;
an active layer provided on the first cladding layer;
a second cladding layer provided on the active layer and having a refractive index equal to or less than a refractive index of the first cladding layer;
a contact layer provided on the second cladding layer; and
a phase modulation layer constituted with a basic layer provided at one of a portion between the first cladding layer and the active layer and a portion between the active layer and the second cladding layer and having a predetermined refractive index, and with a plurality of first modified refractive index regions each having a refractive index different from that of the basic layer,
wherein in a state of satisfying the following first to seventh conditions:
the first condition defined that a virtual square lattice formed with square-shaped M 1 (integer of one or more)×N 1 (integer of one or more) unit constituent regions R is set on an X-Y plane including an X-axis and a Y-axis orthogonal to each other and matching one surface of the phase modulation layer including the plurality of first modified refractive index regions, in an XYZ orthogonal coordinate system defined by a Z-axis matching the normal direction and by the X-Y plane;
the second condition defined that coordinates (x, y, z) in the XYZ orthogonal coordinate system satisfy a relationship expressed by the following formulas (1) to (3) with respect to spherical coordinates (r, θ tilt , θ rot ) defined by a radius vector length r, an inclination angle θ tilt from the Z-axis, and a rotation angle θ rot from the X-axis specified on the X-Y plane,
x=r sin θ tilt cos θ rot   (1)

y=r sin θ tilt sin θ rot   (2)

z=r cos θ tilt   (3);

the third condition defined that letting a beam pattern corresponding to the optical image outputted from the semiconductor light-emitting device be a set of bright spots directed in a direction defined by the angles θ tilt and θ rot , the angles θ tilt and θ rot are converted into a coordinate value k x on a Kx-axis corresponding to the X-axis, that is, a normalized wavenumber defined by the following formula (4) and into a coordinate value k y on a Ky-axis corresponding to the Y-axis and orthogonal to the Kx-axis, that is, a normalized wavenumber defined by the following formula (5),

k
x

=

a
2

⁢
sin
⁢

⁢

θ
tilt

⁢
cos
⁢

⁢

θ
rot

(
4
)

k
y

=

a
λ

⁢
sin
⁢

⁢

θ
tilt

⁢
sin
⁢

⁢

θ
rot

(
5
)

a: lattice constant of the virtual square lattice
λ: oscillation wavelength of the semiconductor light-emitting device;
the fourth condition defined that a specific wavenumber range including the beam pattern is constituted with square-shaped M 2 (integer of one or more)×N 2 (integer of one or more) image regions FR in a wavenumber space defined by the Kx-axis and the Ky-axis;
the fifth condition defined that a complex amplitude F (x, y) is given by the following formula (6) with j being an imaginary unit, the complex amplitude F (x, y) being obtained, in the wavenumber space, by performing two-dimensional inverse Fourier transform on an image region FR (k x , k y ) specified individually by a coordinate component k x (integer of one or more and M 2 or less) in the Kx-axis direction and a coordinate component k y (integer of one or more and N 2 or less) in the Ky-axis direction so as to be transformed onto a unit constituent region R (x, y) on the X-Y plane, specified by a coordinate component x (integer of one or more and M 1 or less) in the X-axis direction and a coordinate component y (integer of one or more and N 1 or less) in the Y-axis direction,

F
⁡

(

x
,
y

)

=

∑

k
x

=
1

M
⁢

⁢
2

⁢

⁢

∑

k
y

=
1

Assignees

• Hamamatsu Photonics Kk

Inventors

• Hirose Kazuyoshi
• Kurosaka Yoshitaka
• Sugiyama Takahiro
• Takiguchi Yuu
• Nomoto Yoshiro

Classifications

• H01S5/3434

  with a well layer comprising at least both As and P as V-compounds · CPC title

• H01S5/2031

  characterized by special waveguide layers, e.g. asymmetric waveguide layers or defined bandgap discontinuities · CPC title

• H01S5/42

  Arrays of surface emitting lasers · CPC title

• H01S5/04256

  characterised by the configuration · CPC title

• H01S5/0287

  Facet reflectivity · CPC title