JP2002185085A5

JP2002185085A5 -

Info

Publication number: JP2002185085A5
Application number: JP2000376846A
Authority: JP
Filing date: 2000-12-12
Publication date: 2004-12-16

Description

【０００４】
【課題を解決するための手段】
本発明の窒化物系半導体レーザ素子は、窒化ガリウム系半導体基板と、窒化ガリウム系半導体基板上に積層された半導体層を備えた窒化物系半導体レーザ素子において、窒化ガリウム系半導体基板の裏面の表面ラフネスＲａが３００Å以下であることを特徴とする。[0004]
[Means for Solving the Problems]
Nitride-based semiconductor laser device of the present invention, a gallium nitride semiconductor substrate, the nitride-based semiconductor laser device comprising a semiconductor layer stacked on the gallium nitride-based semiconductor substrate, the surface back side of the gallium-based semiconductor substrate nitride It is characterized in that the roughness Ra is 300 Å or less.

【０００６】
本発明のチップ分割方法は、窒化ガリウム系半導体基板上に半導体積層構造を形成する工程と、窒化ガリウム系半導体基板の所定の位置に傷をつける工程と、傷に沿って窒化ガリウム系半導体基板を劈開で分割する工程とを含むチップ分割方法において、半導体積層構造を形成する工程と窒化ガリウム系半導体基板の所定の位置に傷をつける工程との間に、基板裏面のラフネスＲａを３００Å以下になるように研磨する工程を含むことを特徴とする。[0006]
Chip dividing method of the present invention includes the steps of forming a semiconductor multilayer structure on the gallium nitride-based semiconductor substrate, a step of scratching in place of the gallium nitride-based semiconductor substrate, a gallium nitride-based semiconductor substrate along the scar in the chip dividing method comprising the step of dividing at cleavage, between the step of damaging the predetermined position of the step and the gallium nitride semiconductor substrate forming the semiconductor multilayer structure, comprising a roughness Ra of the back surface of the substrate to 300Å or less And polishing.

【０００８】
【数１】

[0008]
[Equation 1]

【００１０】
【発明の実施の形態】
一般に、窒化物半導体の結晶成長を行う方法としては、有機金属気相成長法（以下ＭＯＣＶＤ法という）、分子線エピタキシー法、ハイドライド気相成長法（以下ＨＶＰＥ法という）、で行うのが通例であり、どの結晶成長法を用いてもよい。以下に、基板としてＧａＮ基板を用い、成長法としてＭＯＣＶＤ法を用いて製造した窒化物半導体レーザの例について記述する。基板としては、窒化物半導体で構成されている基板であれば良く、Ａｌ _x Ｇａ _y Ｉｎ _z Ｎ _1-x-y-z 基板であっても良い。また、Ａｌ _x Ｇａ _y Ｉｎ _z Ｎ _1-x-y-z 基板（六方晶系）の窒素元素の内、約１０％程度以下が、Ｐ、Ａｓ、Ｓｂの他のＶ族元素に置換されていてもよい。特に、窒化物半導体レーザの場合、垂直横モードの単峰化のために、クラッド層よりも屈折率の低い層が該クラッド層の外側に接している必要があり、ＡｌＧａＮ基板を用いるのが最良である。また、本発明の場合、用いる基板は、窒化物半導体のＣ面基板が好ましい。基板面のオフ角度は±３度を適用の範囲とする。[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Generally, as a method of crystal growth of a nitride semiconductor, it is common practice to carry out by metal organic chemical vapor deposition (hereinafter referred to as MOCVD), molecular beam epitaxy, hydride vapor phase epitaxy (hereinafter referred to as HVPE). Yes, any crystal growth method may be used. Hereinafter, an example of a nitride semiconductor laser manufactured using a GaN substrate as a substrate and using an MOCVD method as a growth method will be described. The substrate may be a substrate made of a nitride semiconductor, and may be an Al _x Ga _y In _z N _1-xyz substrate . Further, about 10% or less of the nitrogen elements in the Al _x Ga _y In _z N _1-xyz substrate (hexagonal system) may be substituted with another group V element of P, As, or Sb. In particular, in the case of a nitride semiconductor laser, a layer having a refractive index lower than that of the cladding layer needs to be in contact with the outside of the cladding layer for monomodalization of the vertical transverse mode, and it is best to use an AlGaN substrate. It is. In the case of the present invention, the substrate used is preferably a nitride semiconductor C-plane substrate. The off angle of the substrate surface is in the range of application of 3 degrees ±.

【００４８】
また今回、研磨工程を終了したＧａＮ基板の最終的な膜厚は１００μｍとしたが基板膜厚の範囲として４０μｍから４４０μｍの範囲が好ましい。４４０μｍ以上では基板裏面のラフネスＲａを３００Å以下に制御した場合であっても上記に示した効果が見られず、分割の歩留まりは５０％以下に低下した。更に、４０μｍ以下にすると、膜に過度にかかる歪の効果のために基板裏面のラフネスＲａを３００Å以下に制御した場合であっても、意図しない方向にクラックが入る等の問題が確認され、分割の歩留まりは、やはり５０％以下に低下してしまった。[0048]
Also, the final film thickness of the GaN substrate completed the polishing step is 100 μm , but the range of the substrate film thickness is preferably 40 μm to 440 μm . If it is 440 μm or more, the above-mentioned effect can not be seen even when the roughness Ra of the back surface of the substrate is controlled to 300 Å or less, and the yield of division is reduced to 50% or less. Furthermore, if the thickness is 40 μm or less, problems such as cracking in an unintended direction are confirmed even when the roughness Ra of the back surface of the substrate is controlled to 300 Å or less because of the effect of strain applied excessively to the film. The split yield has also dropped to 50% or less.

Claims

A gallium nitride semiconductor substrate, the nitride-based semiconductor laser device comprising a semiconductor layer laminated on the gallium nitride-based semiconductor substrate, the surface roughness Ra of the back surface of the gallium nitride-based semiconductor substrate is 300Å or less A nitride-based semiconductor laser device characterized by

The nitride-based semiconductor laser device according to claim 1, wherein Cl is added to the gallium nitride-based semiconductor substrate.

Forming a semiconductor multilayer structure in a gallium nitride-based semiconductor substrate, a step of scratching in place of the gallium nitride-based semiconductor substrate, the step of dividing by cleaving the GaN-based semiconductor substrate along the scar in the chip dividing method including bets, said forming a semiconductor multilayer structure, wherein between the step of scratching in place of the gallium nitride-based semiconductor substrate, 300 Å roughness Ra of the GaN-based semiconductor substrate backside A chip dividing method comprising the step of polishing as follows.