JPS605585A - Semiconductor laser - Google Patents

Semiconductor laser

Info

Publication number
JPS605585A
JPS605585A JP11294783A JP11294783A JPS605585A JP S605585 A JPS605585 A JP S605585A JP 11294783 A JP11294783 A JP 11294783A JP 11294783 A JP11294783 A JP 11294783A JP S605585 A JPS605585 A JP S605585A
Authority
JP
Japan
Prior art keywords
layer
active layer
type
clad
layers
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP11294783A
Other languages
Japanese (ja)
Inventor
Akihiro Matoba
的場　昭大
Koichi Imanaka
今仲　行一
Akira Watanabe
彰 渡辺
Kazuya Sano
一也 佐野
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Oki Electric Industry Co Ltd
Original Assignee
Oki Electric Industry Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Oki Electric Industry Co Ltd filed Critical Oki Electric Industry Co Ltd
Priority to JP11294783A priority Critical patent/JPS605585A/en
Publication of JPS605585A publication Critical patent/JPS605585A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/30—Structure or shape of the active region; Materials used for the active region
    • H01S5/32—Structure or shape of the active region; Materials used for the active region comprising PN junctions, e.g. hetero- or double- heterostructures
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/20—Structure or shape of the semiconductor body to guide the optical wave ; Confining structures perpendicular to the optical axis, e.g. index or gain guiding, stripe geometry, broad area lasers, gain tailoring, transverse or lateral reflectors, special cladding structures, MQW barrier reflection layers
    • H01S5/2004—Confining in the direction perpendicular to the layer structure
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/30—Structure or shape of the active region; Materials used for the active region
    • H01S5/32—Structure or shape of the active region; Materials used for the active region comprising PN junctions, e.g. hetero- or double- heterostructures
    • H01S5/3211—Structure or shape of the active region; Materials used for the active region comprising PN junctions, e.g. hetero- or double- heterostructures characterised by special cladding layers, e.g. details on band-discontinuities
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/30—Structure or shape of the active region; Materials used for the active region
    • H01S5/32—Structure or shape of the active region; Materials used for the active region comprising PN junctions, e.g. hetero- or double- heterostructures
    • H01S5/323—Structure or shape of the active region; Materials used for the active region comprising PN junctions, e.g. hetero- or double- heterostructures in AIIIBV compounds, e.g. AlGaAs-laser, InP-based laser
    • H01S5/32308—Structure or shape of the active region; Materials used for the active region comprising PN junctions, e.g. hetero- or double- heterostructures in AIIIBV compounds, e.g. AlGaAs-laser, InP-based laser emitting light at a wavelength less than 900 nm

Landscapes

  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Optics & Photonics (AREA)
  • Semiconductor Lasers (AREA)

Abstract

PURPOSE:To enable to perform high output with a thick active layer by asymmetrically forming the refractive indexes of two clad layers, between which an active layer is interposed, and increasing the leakage of a light from the active layer than symmetrical waveguides in the same active layer thickness. CONSTITUTION:An N type Ga1-xAlx-1As clad layer 12, a Ga1-yAlyAs active layer 13, a P type Ga1-x2Alx2As clad layer 14, and an N type GaAs cap layer 15 are sequentially grown on an N type GaAs layer substrate 11. The composition ratio of aluminum is set among the layers to x2>x1>y or x1>x2>y. When a forward voltage is applied, a current is concentrated to a diffused strip 16, and flowed, carried is enclosed in the layer 13 directly under it to form an inverted distribution. The light is enclosed in the layer 13, waveguided, amplified between mirrors formed by cleaving, and a laser oscillation is performed. At this time, since the refractive indexes of the layers 12, 13 are asymmetrical to the layer 13, the waveguided beam becomes the flared shape cut largely at the skirt at the clad layer having low refractive index to decrease the rate of waveguiding the layer 13, thereby increasing the output.

Description

【発明の詳細な説明】 （技術分野） この発明は、ダブルへテロ構造の半導体レーザに関する
ものである。DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a double heterostructure semiconductor laser.

（従来技術） 従来の半導体レーザを第１図に示す。この図において、
１はｎ型ＧａＡｓ基板、２はＮ型Ｇａｔ−ｘＡｔｘＡｓ
クラッド層、３はＧａ　１−ｙ　ＡｔｙＡｓ活性層、４
はＰ型Ｇａ　１−ＸＡｔｘＡｓクラッド層、５はｎ型Ｇ
ａＡｓキャップ層、６はＰ型拡散ストライプ、７はＰ型
オーミック電極、８はＮ型オーミック電極である。(Prior Art) A conventional semiconductor laser is shown in FIG. In this diagram,
1 is an n-type GaAs substrate, 2 is an N-type Gat-xAtxAs
Cladding layer, 3 is Ga 1-y AtyAs active layer, 4
is P-type Ga 1-XAtxAs cladding layer, 5 is n-type G
an aAs cap layer, 6 a P-type diffusion stripe, 7 a P-type ohmic electrode, and 8 an N-type ohmic electrode.

これから明らかなように、従来の半導体レーザは、厚み
方向は、ｎ型（またはｐ型）基板上で、発光部となる活
性層を、屈折率の低い半導体層で挾んだ構造となってい
る。この時、厚み方向の屈折率分布は、活性層を挾んで
対称である。As is clear from this, conventional semiconductor lasers have a structure in which an active layer serving as a light emitting part is sandwiched between semiconductor layers with a low refractive index on an n-type (or p-type) substrate in the thickness direction. . At this time, the refractive index distribution in the thickness direction is symmetrical across the active layer.

このような対称な導波路のレーザで高出力化を図るには
、活性層を帆１１１ｍ以下に薄くして導波ビームを活性
層の外へ漏らし、活性層内でのフォトン密度を下げる必
要がある。しかしながら、０．１μｍ以下の薄い活性層
の形成は再現性が悪く、素子歩留シの向上を期待できな
いうえ、結晶性にも難がある。In order to achieve high output with a laser with such a symmetrical waveguide, it is necessary to make the active layer thinner than 111 m, allowing the waveguide beam to leak out of the active layer and lowering the photon density within the active layer. be. However, the formation of a thin active layer with a thickness of 0.1 μm or less has poor reproducibility and cannot be expected to improve device yield, and there are also problems with crystallinity.

（発明の目的） この発明は上記の点に鑑みなされたもので、従来の場合
よシ厚い活性層厚で高出力化を可能とした半導体レーザ
を提供することを目的とする。(Object of the Invention) The present invention has been made in view of the above points, and an object of the present invention is to provide a semiconductor laser that can achieve high output with a thicker active layer than the conventional case.

（実施例） 以下この発明の一実施例を図面を参照して説明する。第
２図はこの発明の一実施例を示す図である。この図にお
いて、１１はｎ型ＧａＡｓ基板で、その上にＮ型Ｇａ　
１−ＸＩ　Ａｔｚ、　Ａ８クラッド層１２、Ｇａ　ｉ−
ｙ　ｋｌ−ｙ　Ａｓ活性層１３、Ｐ型Ｇａ　１−Ｘ２Ａ
Ａｘ２Ａｓクララド／ｉ’Ａ１４、ｎ型ＧａＡｓキャッ
プ層１５が順次形成される。ここで、ＡＬの組成比は、
各層間でｘ２＞ｘｌ〉ｙまたはｘ、＞　ｘ２＞　Ｖとす
る。すなわち、活性層１３を挾む二つのクラッドＭ１２
．１４のＭ　折率を、活性層１３に対して非対称とする
。(Embodiment) An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 is a diagram showing an embodiment of the present invention. In this figure, numeral 11 is an n-type GaAs substrate, on which is an n-type GaAs substrate.
1-XI Atz, A8 cladding layer 12, Ga i-
y kl-y As active layer 13, P-type Ga 1-X2A
Ax2As Clarado/i'A14 and n-type GaAs cap layer 15 are formed in sequence. Here, the composition ratio of AL is
It is assumed that x2>xl>y or x,>x2>V between each layer. That is, two cladding M12 sandwiching the active layer 13.
．． The M refractive index of 14 is made asymmetric with respect to the active layer 13.

１６ｉ、Ｊ：、レーｆ発振領域をストライプ状とするた
めのＰ型拡散ストライプで、Ｐ型不純物拡散によシキャ
ップ層１５およびクラッド層１４に形成さ才りる。そし
て、このＰ型拡散ストライフ”１６上を含むキャラｆ層
１５の表置にはＰ型オーミック電極１７が形成される。16i, J: A P-type diffusion stripe for making the laser f oscillation region into a stripe shape, and is formed in the cap layer 15 and the cladding layer 14 by P-type impurity diffusion. Then, a P-type ohmic electrode 17 is formed on the surface of the character f layer 15, including on the P-type diffused strife 16.

他方、ｎ型ＧａＡｓ基板１１の裏面にはＮ型オーミック
電極１８が形成される。On the other hand, an N-type ohmic electrode 18 is formed on the back surface of the n-type GaAs substrate 11.

このように構成された素子に順電圧を印力ｎすると、電
流は拡散ストライプ部に集中して流れ、ストライプ１６
直下の活性層１３にキャリアが閉じ込められ、反転分布
が形成される。そして、光は活性層１３に閉じ込められ
て導波し、体間で形成されたミラー間で増幅されレーザ
発振する。この時、クラッド層１２．１４の屈折率が活
性Ｎ１３に対して非対称になっているので、導波ビーム
は、屈折率の低い方のクラッド層に大きくすそをそいた
形となる１、すなわち、導波ビームのうち活性層１３を
導波する割合が下がり、高出力化が図られる。When a forward voltage is applied to the element configured in this way, the current flows concentrated in the diffusion stripe portion, and the stripe 16
Carriers are confined in the active layer 13 directly below, forming population inversion. The light is then confined in the active layer 13 and guided, amplified between mirrors formed between the bodies, and oscillated as a laser. At this time, since the refractive index of the cladding layers 12 and 14 is asymmetric with respect to the active N13, the waveguide beam has a shape with a large base on the cladding layer with a lower refractive index 1, that is, The proportion of the waveguide beam that is guided through the active layer 13 is reduced, and higher output can be achieved.

以上の一実施例に示したような非対称な導波路構造で、
活性層中を導波さルるビームの割合を計算して、対称な
導波路構造と比較してみた。ｘｌ＝０．３　、　ｘ２＝
０．２　、　ｙ＝ｏの非対称な場合と、Ｘ１＝ｌｘ２：
　Ｏ−２、’ｌ　＝　０の対称な導波路の場合の、活性
層へ閉じ込められる光の割合Ｆを活性層厚に対して第３
図に示す。この図では、非対称な場合が点線で、また対
称な場合が実線で示される。この図でわかるように、活
性層厚が０．１５μｊｎｖ下になると、非対称な導波路
の方が光の閉じ込めは悪くなる。With an asymmetric waveguide structure as shown in the above example,
We calculated the proportion of the beam guided through the active layer and compared it with a symmetrical waveguide structure. xl=0.3, x2=
0.2, asymmetric case of y=o and X1=lx2:
In the case of a symmetrical waveguide with O-2,'l = 0, the proportion F of light confined in the active layer is expressed as the third factor with respect to the active layer thickness.
As shown in the figure. In this figure, the asymmetric case is shown by a dotted line, and the symmetric case is shown by a solid line. As can be seen from this figure, when the active layer thickness becomes less than 0.15 μjnv, light confinement becomes worse in the asymmetric waveguide.

このように、非対称な導波路構造んすると（この発明の
一実施例によると）、同一の活性層厚で、対称な導波路
よりも活性層からの光の漏几を大きくすることができる
。したがって、従来の場合、しシ厚い活性層厚にして高
出力化を図ることが可能となるものであり、たとえば第
３図の場合は、活性層厚を最大０．１５μｍとして高出
方化を達成することができる。Thus, an asymmetric waveguide structure (according to one embodiment of the invention) allows for greater light leakage from the active layer than a symmetrical waveguide for the same active layer thickness. Therefore, in the conventional case, it is possible to achieve high output by making the active layer thicker. For example, in the case of FIG. can be achieved.

また、Ｐ側りラッド層の組成Ｘ２を、Ｎ側クラッド層の
組成Ｘ、より大きくすると、レーザの閾値電流の温度変
化を大きくする原因となる、エレクトロンの、ダブルへ
テロバリアからＰ側りラッド層へのオーバーフローを抑
えるξとができ、温度に対して安定な低Ｎ値の信頼性の
高いレーザとなる。Furthermore, if the composition X2 of the P-side cladding layer is made larger than the composition ξ that suppresses overflow to the surface, resulting in a highly reliable laser with a low N value that is stable with respect to temperature.

なお、上記−実ＩＭ例は、拡散ストライプ状造の半導体
レーザにこの発明を適用した場合であるが、この発明は
埋め込み構造とかＣＳ　Ｐ構造の半導体レーザなどにも
適用できる。Although the above-mentioned actual IM example is a case in which the present invention is applied to a semiconductor laser having a diffused stripe structure, the present invention can also be applied to a semiconductor laser having a buried structure or a CSP structure.

（発明の効果） 以上詳述したようにこの発明の半導体レーザは、活性層
を挾む二つのクラッドｈの屈折率を活性層に対して非対
称にして、同一活性層厚では、対称な導波路よりも活性
りからの光の漏ｉＬを大きくすることによル゛、従来の
場合よシ厚い活性層厚で高出力化を達成できる。この発
明の半導体レーザは、光通信の分野やプリンタの分野で
利用できる。(Effects of the Invention) As detailed above, in the semiconductor laser of the present invention, the refractive index of the two claddings h sandwiching the active layer is made asymmetric with respect to the active layer, so that when the thickness of the active layer is the same, a symmetrical waveguide is formed. By increasing the light leakage iL from the active layer, high output can be achieved with a thicker active layer than in the conventional case. The semiconductor laser of the present invention can be used in the field of optical communications and printers.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は従来の半導体レーザを示す断面図、第２図はこ
の発明の半導体レーザの一実施例を示す断面図、第３図
は対称な導波路と非対称な導波路の光の閉じ込め係数の
比較を示す図である。 １２−Ｎ型Ｇａ　ｓ−ｘ、　ＡＩ−Ｘ、　Ａｓクラッド
層、１３・・Ｇａ　１−ｙ　Ａｔｙ　Ａｓ活性層、１４
　・Ｐ型Ｇａ　Ｉ　Ｘ２　ＡＬＸ２　Ａ８クラッド層。 第１図 ６ 第２図 第３図Fig. 1 is a cross-sectional view showing a conventional semiconductor laser, Fig. 2 is a cross-sectional view showing an embodiment of the semiconductor laser of the present invention, and Fig. 3 shows the optical confinement coefficient of a symmetrical waveguide and an asymmetrical waveguide. It is a figure showing a comparison. 12-N type Ga s-x, AI-X, As cladding layer, 13...Ga 1-y Aty As active layer, 14
・P-type Ga I X2 ALX2 A8 cladding layer. Figure 1 6 Figure 2 Figure 3

Claims (1)

【特許請求の範囲】[Claims] 活性層を挾む二つのクラッド層の屈折率を、活性層に対
して非対称としたことを特徴とするダブルへテロ構造の
半導体レーザ。A semiconductor laser with a double heterostructure characterized in that the refractive index of two cladding layers sandwiching an active layer is asymmetric with respect to the active layer.
JP11294783A 1983-06-24 1983-06-24 Semiconductor laser Pending JPS605585A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP11294783A JPS605585A (en) 1983-06-24 1983-06-24 Semiconductor laser

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP11294783A JPS605585A (en) 1983-06-24 1983-06-24 Semiconductor laser

Publications (1)

Publication Number Publication Date
JPS605585A true JPS605585A (en) 1985-01-12

Family

ID=14599497

Family Applications (1)

Application Number Title Priority Date Filing Date
JP11294783A Pending JPS605585A (en) 1983-06-24 1983-06-24 Semiconductor laser

Country Status (1)

Country Link
JP (1) JPS605585A (en)

Similar Documents

Publication Publication Date Title
US3978426A (en) Heterostructure devices including tapered optical couplers
US6285694B1 (en) Semiconductor laser
US4426702A (en) Semiconductor laser device
EP0690533B1 (en) Semiconductor laser having integrated waveguiding lens
JPH1168241A (en) Semiconductor laser
CA1096962A (en) Heterostructure diode injection laser having a constricted active region
JPS589389A (en) Light emitting structure and method of producing same
JP2846668B2 (en) Broad area laser
US4520485A (en) Semiconductor device
JPS605585A (en) Semiconductor laser
JPS6079785A (en) Semiconductor laser device
JPS59227177A (en) semiconductor laser equipment
JPH0422033B2 (en)
US4860299A (en) Semiconductor laser device
JP2706166B2 (en) Semiconductor laser
JP2763781B2 (en) Semiconductor laser device and method of manufacturing the same
JPS622584A (en) Buried structure semiconductor laser and manufacture thereof
JP2968159B2 (en) Method for manufacturing semiconductor laser device
JPS5955085A (en) Semiconductor light emitting device
JPS594870B2 (en) semiconductor light emitting device
JPS61236187A (en) Semiconductor laser device and its manufacture
JPH0446477B2 (en)
JPS6089991A (en) semiconductor light emitting device
JPH04370993A (en) Semiconductor laser device
JPS6129183A (en) Semiconductor laser