JP2011211244A5

JP2011211244A5 -

Info

Publication number: JP2011211244A5
Application number: JP2011164400A
Authority: JP
Filing date: 2011-07-27
Publication date: 2012-12-20

Claims

A method for producing a group III nitride semiconductor laser device, comprising:
Preparing a substrate made of a hexagonal III-nitride semiconductor and having a semipolar principal surface;
Forming a substrate structure having a laser structure including a semiconductor region formed on the semipolar main surface and the substrate, an anode electrode, and a cathode electrode;
Providing a plurality of scribe grooves on the first surface by partially scribing the first surface of the substrate product in the direction of the a-axis of the hexagonal group III nitride semiconductor;
Separating the substrate product by pressing against the second surface of the substrate product to form another substrate product and a laser bar;
After processing the end face of the laser bar, the post-processed laser bar is cut along a cutting plane extending in a direction intersecting the a-axis of the hexagonal group III nitride semiconductor and passing through each of the plurality of scribe grooves. And a step of separating the plurality of group III nitride semiconductor laser elements from the processed laser bar,
The first surface is a surface opposite to the second surface;
The semiconductor region is located between the first surface and the substrate;
The laser bar has first and second end surfaces extending from the first surface to the second surface and formed by the separation,
The first and second end faces constitute a laser resonator of the group III nitride semiconductor laser element,
The anode electrode and the cathode electrode are formed on the laser structure;
The semiconductor region includes a first cladding layer made of a gallium nitride semiconductor of a first conductivity type, a second cladding layer made of a gallium nitride semiconductor of a second conductivity type, the first cladding layer, and the first cladding layer. An active layer provided between the two clad layers,
The first cladding layer, the second cladding layer, and the active layer are arranged along a normal axis of the semipolar principal surface,
The active layer includes a gallium nitride based semiconductor layer,
The c-axis of the hexagonal group III nitride semiconductor of the substrate is inclined at a finite angle ALPHA with respect to the normal axis in the m-axis direction of the hexagonal group III nitride semiconductor,
The first and second end faces intersect the mn plane defined by the m-axis and the normal axis of the hexagonal group III nitride semiconductor,
The scribe is performed using a laser scriber,
A plurality of scribe grooves are formed on the first surface by the scribe,
The first portion included in the side wall surface of the scribe groove and connected to the first surface at one end of the scribe groove is within a range of 45 degrees to 85 degrees with respect to the first surface. The second portion that is inclined at the first inclination angle and is included in the side wall surface and connected to the first surface at the other end of the scribe groove is formed on the first surface. It is inclined at a gradient of the second inclination angle within a range of 10 degrees or more and 30 degrees or less,
The direction from the one end portion of the scribe groove to the other end portion is a direction intersecting with a direction in which the c-axis of the hexagonal group III nitride semiconductor is projected onto the semipolar principal surface,
In the step of forming the another substrate product and the laser bar, separation of the laser bar proceeds in a direction from the one end portion of the scribe groove toward the other end portion,
The distance from the bottom wall surface of the scribe groove to the virtual surface extending from the first surface along the first surface on the bottom wall surface is the distance from the first surface to the second surface. The divided quotient is in the range of 0.05 to 0.4,
The distance from the one end portion or the other end portion of the scribe groove between the two adjacent cut surfaces adjacent to each other to the center plane between the two cut surfaces is 30 μm or more and 100 μm or less. range in the near is,
The angle ALPHA is in the range of 45 degrees to 80 degrees or 100 degrees to 135 degrees,
A method characterized by that.

In the step of forming the substrate product, the substrate is subjected to processing such as slicing or grinding so that the thickness of the substrate is 400 μm or less,
The method according to claim 1 , wherein the second surface is a processed surface formed by the processing or a surface including an electrode formed on the processed surface.

In the step of forming the substrate product, the substrate is polished so that the thickness of the substrate is 50 μm or more and 100 μm or less,
The second surface is a surface including an electrode formed on the polished surface formed by polishing, or the polishing surface, the method described in claim 1 or claim 2, characterized in that.

The method according to claim 1, wherein the substrate is made of any one of GaN, AlGaN, AlN, InGaN, and InAlGaN.