TW476176B - Semiconductor laser device and the manufacturing method thereof - Google Patents

Abstract

The object of the present invention is to provide a red semiconductor laser device for a photo-information processing with a low threshold, high illumination efficiency and low electrical deterioration. The solution according to the present invention comprises: a MQW active layer 4 composed of AlGaInP group material; a p-type first lower coating layer 5, configured on the active layer 4 and composed of (AluGa1-u)0.5In0.5P (0 < u < 1) with the bond gap larger than the active layer 4; and, a current blocking layer 6, configured on the first lower coating layer 5 and composed of (AlzGa1-z)0.5In0.5P (0 < z ≤ 1) with the bond gap larger than the active layer and containing the oxygen atoms as the impurities in 1x10<SP>17</SP> cm<SP>-3</SP> to 5x10<SP>18</SP> cm<SP>-3</SP>. Thus, the III-group atoms between the lattice of the current blocking layer 6 will be decreased, it will not be easy to occur the dopant diffusion effect from the first upper coating layer 5 to the active layer 4.

Description

476176 V. Description of the Invention (1) [Field of the Invention] The present invention relates to a Yining semiconductor laser device and a manufacturing method thereof, and more particularly to a red semiconductor laser device used as an optical information processing device and a manufacturing method thereof. . [Known technical description] Since the knowledge, the two red semiconductor laser devices used as optical information processing have mostly adopted gain-guided wave structures using GaAs current blocking layers. However, recently, a red semiconductor laser device capable of reducing an operating current has been developed by adopting a refractive index guided wave structure in which an A n -I nP layer is used as a current blocking layer. "In the refractive index guided wave structure, since the absorption loss of light 1 in the current blocking layer is small, the threshold current can be reduced, and the luminous efficiency can be improved, so that the operating current can be reduced. The fifth picture is in ELECTRONICS Cross section of a conventional SAS (Self-Aligned Structure) type semiconductor laser device described in LETTERS, Vol. 33, No. 14 (1 9 9 7), ρ. 1 223-1 225 In Figure 5, 101 is an η-GaAs substrate, 102 is an η-type GaAs buffer layer, and 103 is an η-type (A10 · 7GaO · 3). 5 · ηη ·· 5P: F cover layer, 104! Ga I ηP / Α 1 GaInP MQW (Multiple Quantum Well, Mu 11i Quantum ^ Wei 1) active layer. The GalnP / AlGalnP of the MQW described here represents the well | The zone layer is GalnP: the barrier layer is AlGalnP (all below Same as.) | 105 is p-type (A10 · 7GaO · 3) 〇 · 51 η0 · 5P is the first layer of a layer, 106 is η-type A10. 51 η0. 5P current blocking layer, 107 is the current

2118-3546-PF.ptd Page 4 476176

The openings of the current blocking layer 106 of the vias, 108 are P-type (A1 (K7Ga0 3) 0.5 2 η 0 · 5P second overlying layer, etc., 10 is a p-type GaAs contact layer, ι10 is a P-side electrode, 111 is the η-side electrode. 1 丨 2 is the above-mentioned conventional half-body laser device. Hita, Second, the manufacturing method of the semiconductor laser device 丨 2 is described first. The first staggered crystal growth method such as the C \ D method is sequentially formed on the n-type GaAs plate 101: the n-type GaAs layer constituting the ^ -type buffer layer 1Q2, and the n-type lower cladding layer 1. Type 3 of η (Α10 · 7GaO · 3) 0

5111〇.5? Layer, constituting 6 of the active layer 104 &amp; 111? / 11〇3 11 ^ 1 ^ ¥ layer, p-type (A10 · 7GaO · 3) constituting the first upper cover layer 105 〇 · 5ΙηΟ 5P layer and n-type A10 · 5ίη0 · 5P layer constituting the current blocking layer 106. As for the dopants at this time, the n-type dopant can make two stones, and the p-type dopant can use zinc.

Next, two photolithographic plates and wet etching are formed on the current blocking layer 106 to form a strip-shaped opening 107 forming a current path. In addition, by the second epitaxial growth using a crystal growth method such as the μ oc VD method, the p-type (A10.7Ga0.3) 0 · constituting the first upper cladding layer 105 through the opening 1 07 is 0 · The 5Ιη0 · 5P layer is embedded and grown to form a p-type (A10 · 7Ga0 · 3) 0 · 5In0 · 5P layer that constitutes the second upper cladding layer 10 and further forms a contact layer. Floor. Further, a p-side electrode 110 is formed on the surface of the p-type GaAs layer constituting the contact layer 109, and an n-side electrode 111 is formed on the inner surface of the n-type GaAs substrate 101. 'Next, the operation of the semiconductor laser device 112 will be described. If a forward voltage is applied between the η-side electrode 111 and the ρ-side electrode 1 1 〇,

476176 V. Description of the invention (3) The empty layer generated by the pn junction between the current blocking layer 106 and the second upper cover layer 108 will prevent the flow of the electric soil and cause the current to be concentrated, and the current will then pass through The opening 1 07 flows to the active layer 104. If a current above a predetermined threshold flows through the active layer 104, electrons and holes will recombine in the active layer 104, thereby generating laser light. At this time, since the n-type lower cladding layer 103, the first upper cladding layer 105, and the second upper cladding layer 108 have larger bond gaps than the active layer 104, the η-type lower cladding layer 103 The refractive index of the first upper cladding layer 105 and the second upper cladding layer iQg are smaller than the active layer 104, so the laser light is limited to the n-type lower cladding layer 103 and the first upper cladding layer 103. 105 and the second overwhelming sound of 108 night. .1 β ~ In addition, the key gap of the current blocking layer 10 is larger than that of the first upper covering layer 105 and the second upper covering layer 08, so the refraction of the current blocking layer 106 is larger. The rate is smaller than that of the first upper cladding layer 105 and the second upper cladding layer 108, so the horizontal and lateral diffusion of laser light is limited by the current blocking layer 106. Therefore, since it is constituted by a refractive index difference between the upper and lower sides and the left and right sides of the light emitting point of the laser light, the laser light becomes near the effective light point.句 L sentence IT, benevolence [the problem to be solved by the invention], because the semiconductor laser device 112 of the It is constituted as described above, it makes the following ^ growth quality and because of the 1: The mcvd method is 70 (rc to 75 (rc), so when the active layer 104 is formed, the upper cover layer 105 and the current blocking layer 106 of the wind first,

476176 V. Description of the invention (4) *-The word has diffused from the upper cover layer 05 to the active layer 104. Furthermore, the second epitaxial growth of the lamp is performed by &amp; at the same temperature, so zinc will diffuse from the upper cover layer 105 to the active layer. In order to realize the refractive index guided wave structure, in addition to the SAS type described in the above-mentioned conventional example, the embedded ridge peak type can also be used to realize it. However, according to recent data, it is known that the upper cladding layer 1 is used. The diffusion of zinc to the active layer 104 is more likely to occur than the ridge peak type, especially one of the SAS type. v 叉 一 'describes other zinc diffusion modes in Journal of Crystal Growth, voll45 (1994) ρ · 80 8-81 2 [Vol. 45 (1994), pp. 808-81 2] One. The diffusion mode of this term (Zη) is explained based on the laminated structure of n-type GaAs / Zn-doped AlGaAs / ge-doped AlGaAs. If this mode is followed, the inter-lattice Ga in Si-doped GaAs will increase with the increase of the carrier concentration of Si and diffuse into the Zn-doped AlGaAs. Because the inter-lattice Ga diffused out above, the η at the Ga position in the interchanged AlGaAs is squeezed out to become inter-lattice Zη, and will diffuse in the layer adjacent to this inter-lattice Zη. Let us consider the above-mentioned zinc diffusion mode in the case of the conventional semiconductor laser device 112. Let the current blocking layer 106 of the η-type A10 · 5Ιη0 · 5P have a function of preventing the 'flow of current' by using a pen layer generated by the ρη junction with the second upper cover layer 108. Therefore, high-concentration doped (@. Therefore, in the current blocking layer 106 of η-type A10 · 5Ιη0 · 5P, A1 or I η corresponding to the group III atom of G a between the lattices in the diffusion mode is considered Yes

2118-3546-PF.ptd Page 7 476176 V. Description of the invention (5) ^ Most of them exist between the crystal lattices, and the group III atoms between the lattices are diffused from the current blocking layer 106 to the p-type (person 10.70.80. 3) The first upper cladding layer 5 ′ of 0.51110.5. 5 and the Zn at the Ga position in the first upper cladding layer 5 is squeezed out, and the discharged inter-lattice Zn is considered to diffuse to Ga I nP / A i Ga ϊ nP MQW active layer 104. The present invention aims to overcome the above-mentioned problems, so its first purpose is to provide a semiconductor laser device with a low threshold current, high luminous efficiency, and high reliability, and its second purpose is to provide a simple and convenient method. Method for manufacturing a highly reliable semiconductor laser device. In addition to the conventional techniques described above, Japanese Patent Application Laid-Open No. 6 2-7 3 6 8 7 also discloses a S AS-type semiconductor laser using an A1 Ga As-based material. Also, in Japanese Patent Application Laid-Open No. 9-33 1 098, a self-excited semiconductor laser including a saturable absorbing layer having a bond gap approximately equal to that of an active layer in a cover layer is disclosed. Doping with oxygen in the saturable absorbing layer makes self-excitation letters easier. [Means to solve the problem] The semiconductor laser device of the present invention includes a GaAs semiconductor substrate of a first conductivity type, and a first cover layer of a first conductivity type, which is disposed on the semiconductor. On the substrate, and is composed of (AlxGai_x) 〇 · 5Ι_π〇 · 5P (0 &lt; χ φ &lt;1); an active layer, which is disposed on the first cover layer, and is bonded by a bond, Bond gap is made of a 1 Gal nP-based material that is smaller than the first cover layer; the first second cover layer of the second conductivity type is arranged on the active layer and is bonded by the bond The gap is larger than the active layer _

2118-3546-PF.ptd Page 8 476176 V. Description of the invention (s) ^ ---------- u) 〇 5 ϊη〇 5p (〇 &lt; u &lt;}); The current blocking means μ has a band-shaped opening that becomes a current path, which is arranged on the first 2 il 2 / benefit layer, and has a larger bond gap than the active layer and contains 1 χ

The oxygen atom of Cm ~ 5 X 1018cm_3 is constituted by (AlzGa ^ z) ^ H = (〇 <Z ^ 1); and a second type A of the second conductivity type & μ, which is an intermediate It is arranged on the first layer through the opening of the current blocking layer, and is composed of a bond gap ratio active layer ... AlC 丨 structure: from η, \ 5P &gt; * (G &lt; V <1, Z &gt; V) Made up. According to the λ of the above-mentioned knot; it can be used to block the thunder by making the current blocking layer contain oxygen atoms. 漭 = two ί group atoms between the lattices of the current blocking layer are reduced. Therefore, 2 ″ ^ 1 2 The dopant diffusion phenomenon of the cover layer is not easy to occur. In addition, the first conductive type is 11 type, the second conductive type is P type, the η type I is ^ X, and the ρ type dopant is zinc, so the above structure makes ϊι, brother 2 Diffusion of zinc overlying layers is unlikely to occur. Furthermore, 'Since the current blocking layer further includes silicon atoms or sulfur atoms having an impurity concentration of 1 X, 1017 cm 3 to 2 X 1 0i8 cm-3, the second structure is made conductive by the above structure. The dopants of the first and second cover layers of the type do not easily diffuse to the current blocking layer, and therefore, the phenomenon of leakage current is not easy to occur at the current blocking layer. In addition, the method for manufacturing a semiconductor laser device according to the present invention includes the step of disembarking: a step of forming a first tomb layer of the first conductivity type, which is formed on a GaAs semiconductor substrate of the first conductivity type by (AlxGai_x) | 〇 · 5ΙηΟ · 5ρ (〇 &lt; x &lt; 1), which is the first covering layer of conductive hair; a step of forming an active layer, which is formed on the first covering layer by Between keys

2118-3546-P? .Ptd Page 9 V. Description of the invention (7) AiGainP series material with a gap smaller than that of the first cover layer forms the second conductive type active layer; formally forms a bond gap ratio The step of the large active layer is the u ^ ^ ^ t ^ ^ ^ 2 νΛ5ίΩ〇 * Ϊΐ〇 &lt; The step of the flow barrier layer, which is at the top] layer / layer; , 2 contains a barrier layer with an impurity degree of lx ι ~ -5χ, and a current port composed of the above-mentioned thunder and glare <ζ ^ 1) · and a π Ϊ Ϊ layer has a current path. The shape-opening step is a step of the second second cover layer of the electro-ΪΪΓ conductive type, the key gate gap of which is opened and the first 21st cover layer is formed, and the bond gap is larger than that of the active layer ( AlvGaiv) (). 5in {). 5p (...... The second covering layer of the second conductivity type of Λ is constructed by the above method. With the anvil described above:? Η P can be manufactured by simple steps. The second conductivity type semiconductor laser device of the first and the cover 0 is difficult to diffuse. [Brief description of the drawings] Figure 1 is a cross-sectional view of the semiconductor laser device of the present invention. Sectional schematic diagram of the MQW active layer of the semiconductor laser device of the invention. Sections 30 (a) and (b) are sectional views of a semiconductor laser manufactured according to the manufacturing process of the semiconductor laser device of the invention. Section 4 Figure 5 is a cross-sectional view of a semiconductor laser device of the present invention. Figure 5 is a cross-sectional view of a conventional semiconductor laser device. [Notation] Bu semiconductor substrate; 3 ~ lower cover layer;

2118-3546-PFl.ptc Page 10 476176 V. Description of the invention (8) 4 ~ MQW active layer; 5 ~ first upper cover layer; 6 ~ current blocking layer; 7 ~ opening; 8 ~ second upper cover Layer; 21 ~ current blocking layer. [Inventive Embodiment] Embodiment 1 FIG. 1 is a sectional view of a semiconductor laser device according to an embodiment of the present invention. Here, as an example of data processing, a red semiconductor laser device of the SAS type with the same laser wavelength of 650 to 685 nm is described. In the first embodiment, the current blocking layer has no current blocking effect due to the empty layer bonded by ρη. Therefore, by doping oxygen atoms in the current blocking layer, it has a high current blocking effect. In this way, the η-type dopant is reduced, so that the diffusion from the first covering layer based on the 11-type dopant to the Zη of the active eyebrow is reduced. In FIG. 1, “1” is an η-type GaAs substrate with a (100) plane as the main surface, which is an off substrate that is inclined only by 100 in the [011] direction; 2 is set up on the above-mentioned GaAs substrate 1 The nsGaAs buffer layer has a layer thickness of 0.5 micron (#m); 3 is a cover layer under the ns (A10.7Ga0.) 0.5 · 1η0 · 5P established on the buffer layer 2 and has a layer thickness of 1 micron. The p-type dopant of the above layer is silicon (S i). ♦ 4 is a (^ 111 [) / 41 (^ 1 heart rate ¥ active layer) provided on the lower cover layer 3. Fig. 2 is a schematic sectional view of the MQW active layer 4 of the semiconductor laser device of the present invention.

Μ Page 11 2118-3546-PF.ptd 476176 V. Description of the invention (9)

In Figure 2, 41 is a light guide layer of (Al (K5Ga0.5) 0.5In0.5P), 42 is a well area layer of GalnP, and 43 is a barrier layer of (A10.5Ga0.5) 0.5In0.5P The above-mentioned MQW active layer 4 is provided with a light guide layer 41 on both sides, and a well zone layer 4 2 is provided by connecting to this light guide layer 41, and between this well zone layer 4 2 and another A structure in which a barrier layer 43 is interposed between one well zone layer 42 and a three-layer barrier layer 43 interposed between four well zone layers 42 constitutes a skewed multiple quantum well structure. —

V can also be seen from the first figure, 5 is the first upper cover layer of p-type (A10 · 7GaO · 3) 0 · 5ΙηΟ · 5P〆, and its layer thickness is 0 · 15 microns; 6 is undoped A 1〇β 5ΙηΟ · 5P current blocking layer, so that its doping concentration as an impurity is ιχ · 1 017cm-3 to 5 X 1 018cnr3 (hereinafter, for example, 1 X 1 〇17 is expressed as 1 ε 1 7 v) Oxygen atom.

The concentration of the oxygen atoms doped here needs to be above 1E1 7 c nr3 in order to have a current blocking effect, and it is necessary to be below 5E18cnr3 in order to reduce the absorption of laser light from the active layer 4 and reduce the reduction in laser characteristics. . V The more preferable range of the above-mentioned oxygen concentration is 5E17cnr3 ~ 1E18cdt3. This is because if the oxygen concentration is too low, Z η will diffuse from the first upper cover layer 5 to the electrically added barrier layer 6 and cause leakage to occur in the current barrier layer 6; the possibility of ^ will easily occur; if If the oxygen concentration is too high, the possibility of light absorption loss will easily occur. Therefore, it is difficult to control the concentration of oxygen generated in the above situation. However, if the above-mentioned level of oxygen is used, In the concentration range, even the slight increase or decrease in the oxygen concentration of the sheath can reduce the error of laser characteristics. The layer thickness of the current blocking layer 6 is 0.7 μm. ,

4/01 / D V. Description of the invention (ίο) 7 is to become a current culvert% (A10. ㈣ of electricity ,: the opening of the barrier layer 6, 8 is the opening 7 of the p-type current blocking layer, and the upper cover layer 'its The buried layer 5 is connected, and it is opened. 07 = '"From this, the opening σ and the first upper cover further cover the electrical part and the electrical contact c, and the degree is 1 micron. 9 is Dl} GaA Ί = Department of the upper cover layer on top of the thick layer 8. Shangcheng go ί touch layer, 'It is arranged on the second cover of the second @ Q 少 Υ I type of knowledge and quality. 1 〇 is ohm The side electrode '11 which is in contact with the contact layer 9 is the η side hail electrode which is in ohmic contact with the inner side of the substrate 1. 12 is the semiconductor laser of the present invention. ^ '' On the semiconductor laser device} The manufacturing method of 2 will be described. Fig. 3 is a cross-sectional view of a semiconductor laser manufactured according to the manufacturing steps of the semiconductor laser device of the present invention. Refer to Fig. 3 (a). First, by the Lizhou MOCVD method, etc. The first telecrystal growth of the crystal growth method is sequentially formed on the n sGaAs substrate 1: an n-type GaAs layer that constitutes a buffer layer 2 and an n-type (A10 · 7Ga (K 3) 0) that constitutes a lower cladding layer 3. · 5ίη0 · 5P layer, GalnP / AlGalnP MQW layer constituting active layer 4, p-type (A10 · 7GaO · 3) 0 · 5ΙηΟ · 5P layer and n-type A1 constituting current blocking layer 6 0 · 5 I η0 · 5P layer. In terms of dopants at this time, ^ -type dopants are used to make silicon, and P-type dopants are used. ~ The epitaxial growth of each layer is set to 700. ° C ~ 7 0 0 ° C, and by switching the source gas to perform. In the formation of the η-type A10 · 5 Ιη0 · 5P layer constituting the current blocking layer 6, the growth temperature is set as follows Low 7 0 0 ° C, V / I ί I ratio is set as a lower level of 1000, and

2118-3546-PF.ptd Page 13 476176 Five 'invention description (11) Doping oxygen atoms from the background At this time, as the impurity ^: Agronomy can be controlled by the growth temperature and y / III ratio, Then, the oxygen concentration as the lambda quality is controlled within the range of 1E17cnr3 to 5E18cnf3 'or even better 5E17cnr3 to iE18cm_3. The results of the above steps are shown in Figure 3 (a). Next, referring to Fig. 3 (b), a strip-shaped opening 7 constituting a current path is formed on the current blocking layer 6 by photoengraving and wet etching. The results of the above steps are shown in Figure 3 (b). 'Second' By using the second epitaxial growth of a crystal growth method such as MOCVD, the first upper cover layer ^ is formed through the opening 7). The 0 · 5Ιη0 · 5P layer is embedded to form the first 2 top cover 8 type 0

Ui.7GaO.3). 5Iη0. 5P layer, and a p-type GaAs layer constituting the contact layer 9 is further formed. Further, ', a p 铡 clad electrode 10 is formed on the surface of the P-type GaAs layer constituting the contact layer 9, and an n-side electrode 11 is formed on the inner surface of the n-type GaAs substrate 1. The result is a semiconductor laser device as shown in FIG. f times, the operation of the semiconductor laser device 12 will be described. Soil = A forward voltage is applied between the osmium electrode 11 and the 9-side electrode 10, and the sale &gt; Chuan · Barrier 6 will increase the impedance due to the nasal loosener M ^ 4 li ^ horse seed mixed with oxygen atoms and therefore has The current blocking effect, so Iridium Mountain, ^ ^ ^ This is the current blocking layer 6 to prevent the flow of current and if there are two or two in the active layer 4 to make the current flow to the active layer 4 more efficiently. The hole will flow through the current on the active layer 4! =, And the shell, J electron, and the hollow core will efficiently recombine from ‘i, and thereby generate laser light. Because of this, Ding Shunjin, —r makes the bottom layer 3, the first upper cover layer 5 and the second

2118-3546-PF.ptd Page 14 V. Description of the invention (12) __ ^ 3 'P !: The upper layer is covered with a key gap larger than the layer, so the n-type lower cover layer is the active layer 4, so the laser beam is emitted. The refractive index of the upper cladding layer 8 of 2 is smaller than that of the upper cladding layer. In particular, the refractive index of the upper cladding layer 8 is limited to between the n-type lower cladding layer 3 and the first cladding layer = the layer 5 and the upper cladding layer 8 of the brother 2. &quot; No. 1 and No.? \ The outer key gap of the current-consuming barrier layer 6 is also larger than the first upper cover M, yield ratio 綮 'The upper key gap of the first 1 layer 8 is larger, so the current barrier layer eV fold = + than the upper cover of the 苐 1 ® 5 LV Ώ _ 1 uses up the refraction of 0. Therefore, the refractive index of the upper cover layer 8 of the laser light 2 is still small. "The diffusion is limited by the current blocking layer 6", because J: Sun, ν, has a refractive index difference to construct the upper and lower and left and right sides of the Γ emission luminous point. The light from Wen Lei will become efficient Confined to the semiconductor laser that is used because the current blocking layer 6 has milk atoms and has a current blocking effect, so in the snow current blocking sound, from the lattice of the current blocking layer 6 to the i-th atom The upper diffusion layer 5 ^ will have less diffusion, and due to the interatomic group atoms, the Zn at the Ga position in the f layer 5 will be squeezed out. Therefore, the brother will also be less. As a result, the diffusion of Zη to the active layer 4 becomes very small. That is, in a semiconductor laser with a conventional structure, a current blocking layer of η-type A10. 51 ηΟ. The empty layer generated by the ρη junction between the second upper cladding layers ι08 prevents current flow, so the current blocking layer 106 is doped with a high concentration of Si.

2118-3546 ^ PF.ptd Page 15

I 476176 V. Description of the invention (13) Therefore, in the current blocking layer 106 of η-type A10 · 5InO. 5P, the A 丨 or 丨 n of ijn group atoms which increase as the Si concentration increases is considered to be the majority Exist in the inter-lattice, the inter-lattice I 11 group atoms will diffuse to the p-type (M 0 · 7GaO · 3) 0 „5ϊη0 · 5P, the first upper cover layer 1 05, and the first The Zη row at the Ga position in the overlying ytterbium layer 105 is extruded, and the discharged inter-lattice Zη is considered to diffuse into the GalnP / AlGalnP MQW active layer 104. Regarding this, the semiconductor laser in Embodiment 1 2 However, since the current blocking layer 6 is doped with oxygen atoms having an impurity concentration of about 1E17cm-3 to 5E18cm_3 to have a current blocking effect, Si as an n-type dopant does not need to be contained at a high concentration. Therefore, With the concentration of Si as an impurity, the group 111 atoms such as A1 and In, which are increased by ^, are considered to be absent. Η Because most of the π group atoms in the intercrystalline lattice in the current blocking layer 6 do not exist, | Therefore, the amount of zeta extruded from the Ga position in the upper cover layer 5 adjacent to the i-th upper barrier layer 6 is also reduced. In the war of Japan and Japan, even if the active layer 4 is formed, Zhijun 'uses the 700 750 C as the growth temperature to form the first upper cover layer 0 and the current blocking layer 6, because The amount of the extruded Zί1 in the cover layer 5 is not large, so that the diffusion to the active layer 4 is changed. Therefore, in the semiconductor laser 12, the light efficiency is reduced. Moreover, the semiconductor laser can be reduced. It can reduce the threshold current and improve the power-on degradation of Tinanfa.

Section of the Semiconductor Laser Device

I V. Description of the invention (14) ------------- Surface view. In the second embodiment, 5 ^ and the ocean bucket-a, ★ '., The machine barrier layer is no current blocking effect field due to the pn junction of the empty layer ~ early and Miangan θ female middle school + Wen%' so by Oxygen is doped into the current blocking layer so that it has a current blocking effect, and thereby reduces the n-type dopant, so as to make it worse than the n-type #quality of the flute. The diffusion of Zr, the first upper cladding layer to the Zri of the active layer becomes 挟% ^ i is the same as in Example 1, except that in the current blocking layer, ΓΓ: Λι is further advanced-doped into several si, so that the diffusion of Zn from the upper cladding layer of Φ1 to φ, ^ / ^ P ^ current blocking layer is reduced. In Figure 4, 20 氐 &amp; and # amα. Is a thousand-conductor laser, and 21 is a current blocking layer. The same symbols as in Example 1 & + _ ^ b are different or equivalent. The flow barrier layer 21 has an oxygen concentration as an impurity and is in accordance with the embodiments. In order to have a current blocking effect, it needs to be above E i 7cm_3, and to reduce the absorption of laser light from the active layer 4 and reduce it. The reduction in laser characteristics is therefore below 5E1 8cm 3. The silicon concentration as an impurity is in the range of 1E17cnr3 to 2E18cnr3. ^ In the current blocking layer 21, by doping Si, the diffusion from the first upper cladding layer 5 to the current blocking layer 21 2: n can be reduced, and leakage at the current blocking layer 21 can be reduced. The possibility of current. Therefore, the oxygen / degree of the current blocking layer 2 can be in the range of 1E1 7 c nr3 to 1E1 8 c nr3, and can also be lower than the range of the first embodiment. In addition, the concentration of silicon as an impurity is in the range of 1E17cnr3 ~ 5E18cm_3 in order to enable it to be on the safer side of the effect on the diffusion of Z η to the active layer described in the Zn diffusion mode. The range is better. In the second embodiment, since the current blocking layer 21 is doped with Si as an impurity, it is possible to prevent the current from passing from the first upper cover layer 5 to the current blocking drawer ^^

476176 May 1st-Description of the Invention 05) Diffusion, that is, the impurity layer, so then, the oxygen concentration is lower than that of the impurity: as above,% can prevent the flow, so it can be more capacitive. Semiconductors are also qualitative, but with a sulfur-like effect. Furthermore, it is made of a material represented by -X S 1) on each of the solid layer 4, the first layer, or the 21 layers. However, if the key gap is larger than the lower overlying layer 3 and the gap is larger, it becomes simpler. In addition, although there is a little diffusion current blocking layer 21, it will not become p-type, which can prevent the flow in f The leakage current of the barrier layer 21 is a. The current blocking layer 6 of Example 1 only contains oxygen as a ratio. Since the current blocking layer 2 of Example 2 can be worked, the possibility of absorption loss of light can be reduced. : By doping oxygen atoms in the current blocking layer 21 and the light absorption loss of the current blocking layer 21 and preventing leakage, the ground is formed with a low threshold current, high luminous efficiency, and poor thunder radiation. In addition, errors in laser characteristics can be reduced. In the known example 2, although s! Is used as the current blocking layer 2 and the ^ -type doped S) is used as the doped semiconductor laser, the same effect can be exerted on the lower cover layer 3 and MQW as described in 1 and 2 ^. Second, the layer 2 and the upper cover layer 8 of the system 2 and the current blocking layer 6 The second and the second system are the materials whose specific aluminum composition ratio is represented by (Aljah) 0.51ηΟ · 5P (0 \ —general formula) In the above-mentioned materials, the MQW active layer is always because the key gap of the current blocking layer 6 or 2 is the key of the upper cover layer 5 of the first and the upper cover layer 8 of the second The material section of each layer can be set relatively freely. A cool barrier layer 'When using the AlInPB strip material, the adjustment will be 0v / ^, A and the semiconductor laser described in Example 1 and 2 are

苐 Page 18 476176 V. Description of the invention (i6) SAS type, but other forms of Zn doped or n-type current blocking layer are formed on top of the active layer. ; _ Tian She can also exert the same effect. [Effect of the invention] The semiconductor laser device of the present invention has such a structure, so it has the following effects. Because the semiconductor laser device of the present invention as described in the specification includes an AlGalnP-based material; a second conductive type &lt; a trinity active layer, the layer 'is disposed on the above active layer and is The second cover is (AiuGai_u) 0.5 In. 5 p (〇 &lt; u &lt;; [), a gap ratio active laminar barrier layer having a band-shaped opening formed as a current path; and an electrical The first and second covering layers mentioned above are beneficially composed of a bond gap ratio, = oxygen atoms arranged in the upper 1 X 1017cnr3 ~ 5 X lCPcnr3 as a heterolayer hole, and containing 5In0.5P ((XZU), Therefore, using the above \ AlzGa! _Z) 0. By making the current blocking layer contain oxygen atoms and breaking off the electricity i ',' Q structure 'can reduce the number of Π group atoms in the grid, and the second function of the second conductivity type 'So Be: Diffusion does not occur easily. At the same time, it can reduce the threshold current of the cover layer and improve the luminous efficiency. Protection, and the total power loss of the total τ conductor laser to improve reliability ^. Q can reduce the semiconductor laser even further. Since the dopant of the nth type "⑼ η is silicon and the dopant of ρ type is zinc, the 'V electric type is ρ type, and the first cover and layer of zinc The composition of the diffusion is not easy, so that the dopant of the type is silicon. The dopant of the P type is / this, which can reduce the current at η value and improve its luminous efficiency. It can also reduce the energization degradation of semiconductor lasers made of zinc (476), which are doped with 476176. (17) In order to improve the reliability. First, because the current blocking layer further contains impurities Silicon atom or sulfur atom with a concentration of i X 1 O17cm—3 to 2 X 1 018cnr3, so by the above-mentioned | composition, the dopant of the second covering layer of the second conductivity type is difficult to spread to the The hail current is a barrier, so it is not easy to cover the leakage current at the current blocking layer. By this, it can be more easily constituted to avoid the loss of light absorption at the current barrier and prevent the leakage of current there. The semiconductor laser device, in addition, can also reduce the error of laser characteristics. Tian π + %% w 卞 守 ... The device manufacturer Wababa · Steps: a step of forming an active layer, this active layer is composed of AiGainP system = material user: a step of forming the second cover layer of the i-th conductive type is active A layer 2 of the second conductivity type composed of the first conductive layer having a larger bond gap than that of the active layer is formed on the layer, and a current blocking layer is formed. ^ 2 The bond gap is formed on the cover layer. In a big step, the beer and human beer at the first degree is an oxygen atom layer of lx 1 (FCm-3 ~ 5x 1018cm-3). 3 There are impurities.

UlnO.SP (0 &lt; "&quot; constitutes an electrically isolated wide barrier layer which has a current path, a barrier layer, and the above-mentioned electricity: the second cover layer of the second type of electrical type, and T A second lead σ is formed, and the second cover layer 2 ^, ', and the second series of the first through the current blocking layer (AM ^ v) 0.5I'n0.5pe (^ 2 because the bond gap is larger than the active layer Of the second type of the second type of the electric type | The second step of the second step that is constituted to make the second step ?: Method C can use the simple-one-to-one coating of dopant is not easy to do

476176

2118-3546-PF.ptd Page 21

Claims (1)

476176 VI. Patent application scope 1. A semiconductor laser device, comprising: a GaAs semiconductor substrate of a first conductivity type; a first cover layer of a first conductivity type, which is disposed on the semiconductor substrate | It is composed of (AixGai_x) 0 · 5ίη0 · 5P (0 &lt; x &lt;1); I is an active layer, which is disposed on the first cover layer, and has a bond gap more than the above. The first cover layer is made of A i Gal ηΡ series material; a second cover layer of the second conductivity type is disposed on the active layer and has a bond gap ratio higher than the above active layer.大 之 （A luGa ^） I 0 · 5ίη0 · 5Ρ (0 &lt; ιι &lt;1); i a current blocking layer, which has a strip-shaped opening that becomes a current path, and is arranged in the first and second On the cover layer, it is composed of (A lzGa ^ z) 0 · 5ίη0 · 5Ρ (0 &lt; ζ $ 1) which has a larger bond gap than the above active layer and contains oxygen atoms of 1 X 1017cm_3 ~ .5 X 1018cm_3 as impurities. ; And a second second cover layer of the second conductivity type, which is disposed on the first second cover through the opening of the current blocking layer Above, and the key is the large gap (AivGaH) than the active layer 0 · 5ΙηΟ · 5P (0 &lt; v v &lt;; 1, z & gt) is constituted. 2. The semiconductor epitaxial device according to item 1 of the scope of patent application, wherein the first conductivity type is η-type, the second conductivity type is p-type, the n-type dopant is silicon, and the p 4 -type dopant is zinc. . 3. The semiconductor laser device according to item 2 of the 'Patent Scope of the Application', wherein the current blocking layer further includes silicon atoms or sulfur atoms having an impurity concentration of 1 X 1017cnr3 to 2 X 1018cnr3. 2118-3546-PF.ptd Page 22 476176 VI. Patent application scope 4 · A method for manufacturing a semiconductor laser device, including the following steps:-A step of forming a first cover layer of the first conductivity type, which is the first step The conductive type GaAs semiconductor substrate i forms a first cover layer of a first conductive type, which is composed of (AlxGabux) 0 · 5Ιη0 · 5P (0 &lt; X &lt;1); a step of forming an active layer, which is An active layer made of an A i Ga I η-based material having a smaller bond gap than the first cover layer is formed on the first cover layer; a step of forming the first second cover layer of the second conductivity type, which is A second covering layer of the second conductivity type is formed on the active layer with a larger bond gap (AluGa ^) 0 · 5Ιη0 · 5P (0 &lt; u &lt;l); a current blocking is formed; Step of the layer, which is formed on the first and second cover layer. The bond gap is larger than that of the active layer and contains an oxygen atom (ALGah) having an impurity concentration of 1 X 1017cm_3 to 5x 1018cm-3. 0 · 5ΙηΟ · 5P (0 &lt; ζ $ 1), and the current blocking layer has a band-shaped opening that becomes a current path And a step of forming the second second cover layer of the second conductivity type, which is formed on the first second cover layer through the opening of the current blocking layer, and the bond gap is larger than that of the active layer ( AkGah) 0 · 5ΙηΟ · 5P (0 &lt; v &lt; 1, z &gt; v) The second and second cover layer of the second conductivity type. 2118-3546-PF.ptd Page 23