JP2009302113A - Surface light emitting laser element and, method of manufacturing laser array, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a surface light emitting laser array (VCSEL) with high reliability, and an image forming apparatus that performs high-speed or high-resolution writing using the manufactured surface light emitting laser array. <P>SOLUTION: The surface light emitting laser single element (VCSEL single element) has DBRs (reflectors) 102 and 106 each made of an AlGaAs high-refractive-index layer and a low-refractive-index layer at least partially different in Al composition, and an active layer 103 sandwiched between the DBRs, and performs current constriction by a selectively oxidized layer 105, wherein a wiring width W2 of mesa-side wall portion wiring which is wiring for implanting a current into the VCSEL element and connects a mesa bottom portion from the upper portion of the mesa of the VCSEL element as a projection portion is wider than a wiring width W3 of wiring formed at the mesa bottom portion as a recessed portion. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a highly reliable two-dimensional surface-emitting laser element, a method for manufacturing a two-dimensional surface-emitting laser array, and an image forming apparatus capable of high-speed or high-resolution writing.

  A surface emitting laser (VCSEL) has a structure in which a laser resonator is formed in a direction perpendicular to a semiconductor substrate, and oscillation light is emitted in a direction perpendicular to the substrate. Specifically, a surface emitting laser (VCSEL) is provided with a pair of high-reflectivity mirrors facing the substrate side and the surface, and an active layer is provided between the pair of mirrors. It has a structure in which two upper and lower spacer layers are provided between the layer and the two reflecting mirrors.

Wiring is formed in one of the manufacturing steps of the VCSEL element. At this time, the P-side upper electrode for injecting current from the upper portion of the VCSEL mesa must be wired over a large step, and wiring step coverage is insufficient. Caused disconnection and poor reliability.
As a structure for eliminating this step coverage shortage, a structure in which the entire mesa side wall is covered with a P-side electrode wiring has been proposed (Japanese Patent Laid-Open No. 2008-34637 (see Patent Document 4)).

Further, as disclosed in Japanese Patent Application Laid-Open No. 2006-013366 (see Patent Document 2) and Japanese Patent Application Laid-Open No. 2007-150170 (see Patent Document 3), the step coverage is improved by making the mesa into a tapered shape. An example is proposed.
On the other hand, as disclosed in Japanese Patent Laid-Open No. 2005-191343 (see Patent Document 1), there is an example in which step coverage is improved by flattening with polyimide.
In addition, it is also possible to secure the metal coverage of the mesa side wall by performing vapor deposition by oblique incidence.

JP 2005-191343 A JP 2006-013366 A JP 2007-150170 A JP 2008-34637 A

As described above, various structures for solving the shortage of step coverage have been proposed.
However, when the P-side electrode wiring is formed on the entire mesa side wall as disclosed in Japanese Patent Application Laid-Open No. 2008-34637 (Patent Document 4), the internal stress of the wiring of the electrode itself acts on the VCSEL element to cause crystal defects. Triggered and caused poor reliability.
Further, as disclosed in Japanese Patent Application Laid-Open No. 2006-013366 (Patent Document 2) and Japanese Patent Application Laid-Open No. 2007-150170 (Patent Document 3), even when the mesa is tapered, the wiring coverage is insufficient. As a result, the film thickness on the mesa side wall is reduced, resulting in poor disconnection and reduced wiring reliability.

  In the case of the structure disclosed in Japanese Patent Application Laid-Open No. 2005-191343 (Patent Document 1), the number of steps for forming polyimide is increased and the cost is increased. In addition, internal stress acts on the VCSEL element, resulting in crystal defects. , Causing poor reliability. On the other hand, in the method of depositing wiring metal from an oblique direction and ensuring the coverage of the mesa side wall, burrs are generated at the end of the wiring formed in the mesa bottom region of the recess, and the wiring burrs become particles in the subsequent process. It caused a short circuit between wires.

(the purpose)
SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, provide a highly reliable surface-emitting laser array manufacturing method, and provide an image forming apparatus capable of high-speed or high-resolution writing using the manufactured surface-emitting laser array. Is to provide.

The above object is achieved by a VCSEL element, a VCSEL array element, an optical scanning device, and an image forming apparatus having the following structure.
1) The VCSEL device of the present invention has an active layer sandwiched between a DBR (reflecting mirror) and a DBR composed of an AlGaAs high-refractive index layer and a low-refractive index layer at least partially different in A1 composition, and a selective oxidation layer In a surface-emitting laser single element (VCSEL single element) that performs current confinement by a wiring, a mesa side wall that connects a mesa bottom to a mesa top of a VCSEL element that is a convex part, is a wiring for injecting current into the VCSEL element The wiring width is characterized in that it is wider than the wiring width formed at the bottom of the mesa that is a recess.
2) In the surface emitting laser single element (VCSEL single element) having the structure 1) above, it is a wiring for injecting a current into the VCSEL element, and the bonding pad region of the VCSEL element which is a convex portion and the mesa which is a concave portion. It is characterized in that the width between the side walls of the convex part connecting the bottom part is wider than the wiring width formed on the mesa bottom part which is a concave part.
3) Surface emission that has an active layer sandwiched between a DBR (reflecting mirror) and a DBR composed of an AlGaAs high-refractive index layer and a low-refractive index layer at least partially different in A1 composition, and performs current confinement by a selective oxidation layer In the laser array element, wiring for injecting current into the VCSEL element, the wiring width of the mesa side wall connecting the mesa bottom to the mesa bottom of the VCSEL element that is the convex part is formed in the mesa bottom part that is the concave part It is characterized by being wider than the wiring width.

4) The VCSEL array element of the present invention is a VCSEL element having the structure of 3) above, and DBR (reflecting mirror) and DBR comprising at least a part of AlGaAs high refractive index layer and low refractive index layer having different A1 compositions. A VCSEL element which is a wiring for injecting a current into a VCSEL element in a surface emitting laser array element (VCSEL array element) having an active layer sandwiched between and selectively confining current by a selective oxidation layer The wiring width of the side wall of the convex part connecting the bonding pad region and the mesa bottom part as the concave part is wider than the wiring width formed at the mesa bottom part as the concave part.
5) An optical scanning device of the present invention is an optical scanning device that scans a surface to be scanned with a light beam, the light source unit having the surface emitting laser array element having any one of the structures 1) and 2) above, It is characterized by comprising deflection means for deflecting the light beam from the light source unit, and a scanning optical system for condensing the deflected light beam on the surface to be scanned.
6) Further, a light source unit having the surface emitting laser array element of any one of the structures 1) and 2), deflecting means for deflecting a plurality of light beams from the light source unit, and a plurality of the stage deflected plural And a scanning optical system for condensing the light beam on the surface to be scanned.

7) At least one image carrier, at least one optical scanning device according to 3) that scans the at least one image carrier with a light beam containing image information, and the at least one image carrier. And a transfer unit that transfers an image formed on the body to a transfer object.
8) Further, at least one image carrier and at least one optical scanning device according to the above 4) that scans the at least one image carrier with a plurality of light beams including image information, and the at least one image carrier. And a transfer means for transferring an image formed on the image carrier to a transfer object.

According to the present invention, since the wiring width of the mesa side wall portion connecting the mesa top portion of the VCSEL element that is the convex portion to the mesa bottom portion is wider than the wiring width formed on the mesa bottom portion that is the concave portion, the step coverage is somewhat insufficient. Even when the film thickness of the wiring on the mesa side wall portion is thin, it is possible to provide a highly reliable wiring without disconnection and to widen the process margin of the wiring process.
Furthermore, a highly reliable optical scanning device can be provided, and a highly reliable image forming apparatus with a long light source life can be provided.

  Hereinafter, the detailed configuration and operation of the present invention will be described with reference to the drawings.

FIG. 1 is a cross-sectional view of an epitaxial growth substrate for producing a surface emitting laser element.
First, an epitaxial growth substrate as shown in FIG. 1 is prepared in order to produce a surface emitting laser element. An Al _0.6 Ga _0.4 As spacer including an active layer 103 made of an A1 _0.12 Ga _0.88 As quantum well layer / A _10.3 Ga _0.7 As obstacle layer on an n-GaAs substrate 101 A resonator region having a thickness of 1 wavelength composed of the layer 104 is 40.5 pairs of n-Al _0.3 Ga _0.7 As high refractive index layer / n-A _{10. An} n-DBR (lower reflector) 102 composed of a ₉ Ga _0.1 As low-refractive index layer and 24 pairs of p-Al _0.3 Ga _0.7 As high-refractive index layers 1061 / p-Al _0.9 Ga _A layer structure sandwiched between p-DBRs (upper reflecting mirrors) 106 composed of a _0.1 As low refractive index layer 1062 is formed.

  Furthermore, an AlAs selectively oxidized layer 105 is provided on the upper reflecting mirror 106 that is λ / 4 away from the resonator region. In addition, between each layer of a reflective mirror, the composition gradient layer from which a composition changes gradually for resistance reduction is included. These crystal growths can be performed using MOCVD or MBE.

Next, a mesa shape and a bonding pad region are simultaneously formed by dry etching.
FIG. 2A is a top view after dry etching, and a cross section taken along line XX ′ is shown in FIG.
In general, the etching surface of dry etching is etched into the n-DBR layer (lower reflecting mirror) 102.
Further, the AlAs selectively oxidized layer 105 whose side surface is exposed in the etching process is heat-treated in water vapor to oxidize from the end face of the mesa, and a current confinement layer that is an Al _x O _y insulator layer (FIG. 3B). (See 1051). That is, a current confinement structure is formed to limit the element drive current path only to the unoxidized AlAs region at the center.

FIG. 3A is a top view after the current confinement layer oxidation step, and FIG. 3B is a sectional view taken along line XX ′.
Subsequently, an interlayer insulating film such as SiO ₂ , SiN, or SiON is formed on the entire surface by plasma CVD.

4A is a top view after the interlayer insulating film forming step, and FIG. 4B is a cross-sectional view taken along the line XX ′.
Further, the p-side electrode contact layer 107 and the interlayer insulating layer 108 on the upper reflecting mirror 106 having the light emitting portion are removed by etching to form a contact hole (see 112 shown in FIG. 5B).

FIG. 5A is a top view after the contact hole forming step, and FIG. 5B is an XX ′ cross-sectional view thereof.
Next, the p-side wiring electrode is formed by a lift-off method.
At this time, the wiring width W2 of the mesa side wall is less than or equal to the wiring width W1 of the upper part of the mesa and is larger than the wiring width W3 of the bottom of the mesa. Further, the wiring width W4 formed at the step between the VCSEL formation region and the bonding pad region is equal to or smaller than the wiring width W5 of the bonding pad region and larger than the wiring width W3 at the bottom of the mesa. In this way, the n-side electrode 110 was formed on the back surface of the substrate.

Here, the reason why the wiring width W1 of the upper part of the mesa that is the convex part and the wiring width W5 of the bonding pad area are made larger than the wiring width W3 of the concave part is as follows.
1) The wiring capacity is reduced to enable high-speed operation.
2) In the case of an array element, the layout design margin of wiring increases when a large number of VCSEL elements are formed. For this reason, it becomes easy to array many VCSEL elements.

In the case of the present embodiment, as shown in FIGS. 2A and 2B, the mesa portion formed by the dry etching method becomes each surface emitting laser element. The method of forming the array arrangement of the present invention can be formed by forming a photomask along the array arrangement of the present invention, forming an etching mask by a normal photolithography process, and etching.
In this way, by forming a wiring having a wiring width at the mesa side wall wider than that at the bottom of the mesa, a p-side wiring having low resistance and high reliability can be formed.

  In this embodiment, an example in which the configuration of the present invention is applied to the VCSEL element mesa that emits light and the step formed between the VCSEL element mesa and the bonding pad region is shown, but the configuration is the same as the VCSEL element mesa that emits light. The present invention can also be applied to all the steps of the wiring that steps the dummy mesa that does not emit light.

FIG. 7 is a sectional structural view of a surface emitting laser device according to an embodiment of the present invention.
On the n-GaAs substrate 101 adjacent to the n-side electrode 110, an active layer 103 composed of an A1 _0.12 Ga _0.88 As quantum well layer / A _l0.3 Ga _0.7 As obstacle layer is provided, and Al _{0 .6} Ga _0.4 As spacer layer 104 and a one-wavelength-thickness resonator region, 40.5 pairs of n-Al _0.3 Ga _0.7 As high refractive index with an optical thickness of each layer λ / 4 Index layer / n-DBR (lower reflector) 102 made of n-A _10.9 Ga _0.1 As low-refractive index layer and 24 pairs of p-Al _0.3 Ga _0.7 As high-refractive index layer 1061 / P-Al _0.9 Ga _0.1 As A layer structure sandwiched between p-DBRs (upper reflecting mirrors) 106 composed of a low refractive index layer 1062 is formed.

An AlAs selectively oxidized layer 105 is provided on the upper reflecting mirror 106 that is λ / 4 away from the resonator region. A current confinement layer 1051, which is an Al _x O _y insulator layer, is formed therebelow. The light output is output from a light emitting portion 111 that is a contact hole 112 formed on the p-side electrode 109.

<Laser printer>
FIG. 8 is a schematic configuration diagram of a laser printer which is an image forming apparatus according to an embodiment of the present invention.
The laser printer 500 includes an optical scanning device 900, a photosensitive drum 901, a charging charger 902, a developing roller 903, a toner cartridge 904, a cleaning blade 905, a paper feeding tray 906, a paper feeding roller 907, a registration roller pair 908, and a transfer charger 911. , A static elimination unit 914, a fixing roller 909, a paper discharge roller 912, a discharge tray 910, and the like.

  The charging charger 902, the developing roller 903, the transfer charger 911, the charge removal unit 914, and the cleaning blade 905 are each disposed in the vicinity of the surface of the photosensitive drum 901. Then, with respect to the rotation direction of the photosensitive drum 901, the charging charger 902, the developing roller 903, the transfer charger 911, the static elimination unit 914, and the cleaning blade 905 are arranged in this order.

A photosensitive layer is formed on the surface of the photosensitive drum 901. Here, the photosensitive drum 901 rotates clockwise (in the direction of the arrow) within the plane in FIG.
The charging charger 902 uniformly charges the surface of the photosensitive drum 901.
The optical scanning device 900 irradiates the surface of the photosensitive drum 901 charged by the charging charger 902 with light modulated based on image information from a host device (for example, a personal computer). As a result, a latent image corresponding to the image information is formed on the surface of the photosensitive drum 901 on the surface of the photosensitive drum 901. The latent image formed here moves in the direction of the developing roller 903 as the photosensitive drum 901 rotates. The configuration of the optical scanning device 900 will be described later.

The toner cartridge 904 stores toner, and this toner is supplied to the developing roller 903.
The developing roller 903 causes the toner supplied from the toner cartridge 904 to adhere to the latent image formed on the surface of the photosensitive drum 901 to visualize the image information. Here, the latent image to which the toner is attached moves in the direction of the transfer charger 911 as the photosensitive drum 901 rotates.

  A recording sheet 913 is stored in the sheet feeding tray 906. A paper feed roller 907 is disposed in the vicinity of the paper feed tray 906, and the paper feed roller 907 takes out the recording paper 913 one by one from the paper feed tray 906 and conveys it to the registration roller pair 908. The registration roller pair 908 is disposed in the vicinity of the transfer roller 911, temporarily holds the recording paper 913 taken out by the paper feed roller 907, and the recording paper 913 is synchronized with the rotation of the photosensitive drum 901. It is sent out toward the gap between 901 and the transfer charger 911.

A voltage having a polarity opposite to that of the toner is applied to the transfer charger 911 in order to electrically attract the toner on the surface of the photosensitive drum 901 to the recording paper 913. With this voltage, the latent image on the surface of the photosensitive drum 901 is transferred to the recording paper 913. The recording sheet 913 transferred here is sent to the fixing roller 909.
In the fixing roller 909, heat and pressure are applied to the recording paper 913. As a result, the toner is fixed on the recording paper 913. The recording paper 913 fixed here is sent to the paper discharge tray 910 via the paper discharge roller 912 and sequentially stacked on the paper discharge tray 910.

The neutralization unit 914 neutralizes the surface of the photosensitive drum 901.
The cleaning blade 905 removes toner remaining on the surface of the photosensitive drum 901 (residual toner). The removed residual toner is used again. The surface of the photosensitive drum 901 from which the residual toner has been removed returns to the position of the charging charger 902 again.

<Optical scanning device>
FIG. 9 is an explanatory diagram of the configuration and operation of the optical scanning device (900) of FIG.
The optical scanning device 900 includes a light source unit 10 including the surface emitting laser array LA, a coupling lens 11, an aperture 12, a cylindrical lens 13, a polygon mirror 14, an fθ lens 15, a toroidal lens 16, and two mirrors (17, 18). ), And a main control device (not shown) for comprehensively controlling the above-described units.

The coupling lens 11 shapes the light beam emitted from the light source unit 10 into substantially parallel light.
The aperture 12 defines the beam diameter of the light beam that has passed through the coupling lens 11. The cylindrical lens 13 condenses the light beam that has passed through the aperture 12 on the reflecting surface of the polygon mirror 14 via the mirror 17.

  The polygon mirror 14 is formed of a regular hexagonal columnar member having a low height, and six deflection surfaces are formed on the side surface. A rotating mechanism (not shown) is rotated at a constant angular velocity in the direction of the arrow shown in FIG. Therefore, the light beam emitted from the light source unit 10 and condensed on the deflection surface of the polygon mirror 14 by the cylindrical lens 13 is deflected at a constant angular velocity by the rotation of the polygon mirror 14.

The fθ lens 15 has an image height proportional to the incident angle of the light beam from the polygon mirror 14, and the image plane of the light beam deflected by the polygon mirror 14 at a constant angular velocity is made constant with respect to the main scanning direction. Move.
The toroidal lens 16 forms an image of the light beam from the fθ lens 15 on the surface of the photosensitive drum 901 via the mirror 18.

FIG. 10 is a diagram for explaining the resolution when the surface emitting laser array is used.
In this case, if the surface emitting laser array LA is arranged as shown in FIG. 10, in the surface emitting laser array LA, a vertical line extends from the center of each surface emitting laser element (VCSEL) in a direction corresponding to the sub-scanning direction. Since the positional relationship between the surface emitting laser elements in the direction corresponding to the sub-scanning direction at the time of lowering is equal (interval d2), the sub-scanning is performed on the photosensitive drum 901 by adjusting the lighting timing. This can be regarded as the same configuration as when light sources are arranged at equal intervals in the direction. For example, if the pitch d1 of the surface emitting laser elements in the direction corresponding to the sub-scanning direction is 26.5 μm, the interval d2 is 2.65 μm. If the magnification of the optical system is doubled, writing dots can be formed on the photosensitive drum 901 at intervals of 5.3 μm in the sub-scanning direction. This corresponds to 4800 dpi (dots / inch). That is, high-density writing of 4800 dpi (dot / inch) can be performed. Of course, if the number of surface emitting lasers in the direction corresponding to the main scanning direction is increased, an array arrangement in which the distance d2 is further reduced with the pitch d1 interposed therebetween, or the magnification of the optical system is decreased, the higher the number of surface emitting lasers. Densification can be achieved, and higher quality printing becomes possible. Note that the writing interval in the main scanning direction can be easily controlled by the lighting timing of the light source.

  In this case, the laser printer 500 can perform printing without reducing the printing speed even if the writing dot density increases. Further, when the writing dot density is the same, the printing speed can be further increased.

  In the surface emitting laser array LA, since the wire disconnection defects on the mesa side wall, the dummy mesa side wall, and the bonding region side wall portion are reduced, a high yield and high reliability VCSEL array can be realized even if the array is formed. A high-definition image can be formed at high speed.

  As described above, according to the optical scanning device 900 according to the present embodiment, the light source unit 10 includes the surface emitting laser array LA, and thus can operate at a higher output than the conventional one. It becomes possible to scan the surface of the body drum 901 at high speed.

  Further, since the laser printer 500 according to the present embodiment includes the optical scanning device 900 including the surface emitting laser array LA, a high-definition image can be formed at high speed.

  Further, even an image forming apparatus that forms a color image can form a high-definition image at a high speed by using an optical scanning device corresponding to the color image.

  Further, the image forming apparatus may be a tandem color machine that corresponds to a color image and includes, for example, a photosensitive drum for black (K) and a photosensitive drum for cyan (C).

(Function)
1) Since the wiring width of the mesa side wall connecting the mesa top to the mesa bottom of the VCSEL element that is a convex part is wider than the wiring width formed on the mesa bottom part of the convex part, the step coverage is somewhat insufficient, and the mesa side wall Even when the thickness of the wiring in the portion is thin, it is possible to provide a highly reliable wiring without disconnection and to widen the process margin of the wiring process (claims 1 and 3). .

2) Since the wiring width of the side wall of the convex portion that connects the bonding pad region of the VCSEL element that is the convex portion and the mesa bottom portion that is the concave portion is wider than the wiring width formed on the mesa bottom portion that is the concave portion, the step coverage is somewhat Even when the film thickness of the wiring on the mesa side wall portion is insufficient, a highly reliable wiring without disconnection can be provided and the process margin of the wiring process can be widened. Item 2, 4).

3) Since the optical scanning device of the present invention uses a surface emitting laser array element, a highly reliable optical scanning device can be realized (claims 5 and 6).

4) Since the image forming apparatus of the present invention performs writing by an optical scanning device using a surface emitting laser array element, the life of the light source is long and the reliability is high (claims 7 and 8).

It is sectional drawing of the epitaxial growth board | substrate for producing a surface emitting laser element. It is the upper side figure after dry etching, and its X-X 'sectional drawing. It is the upper side figure after an electric current confinement layer oxidation process, and its X-X 'sectional drawing. It is the top view after an interlayer insulation film formation process, and its X-X 'sectional view. It is the upper side figure after a contact hole formation process, and its X-X 'sectional drawing. It is a figure which shows the dimension value of each part in FIG. 1 is a cross-sectional structure diagram of a surface emitting laser element according to an embodiment of the present invention. 1 is a schematic configuration diagram of a laser printer which is an image forming apparatus according to an embodiment of the present invention. It is explanatory drawing about a structure and effect | action of the optical scanning device of FIG. It is a figure for demonstrating the resolution when a surface emitting laser array is used.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Light source unit 11 Coupling lens 12 Aperture 13 Cylindrical lens 14 Polygon mirror 15 f (theta) lens 16 Toroidal lens 17 Light beam mirror 18 Light beam mirror
101 n-GaAs substrate 102 n-DBR (lower reflector)
103 Active layer 104 Spacer layer 105 AlAs selective oxidation layer (current injection part)
1051 AlxOy current confinement layer 1052 AlAs selective oxidation layer (current injection part)
106 p-DBR (upper reflector)
1061 AL _0.3 Ga _0.7 As
1062 Al _0.9 Ga _0.1 As
107 p-GaAs contact layer 108 Interlayer insulating layer 109 P-side electrode wiring 110 n-side electrode 111 Light emitting portion 112 Contact hole 500 Laser printer 900 Optical scanning device 901 Photosensitive drum (image carrier)
902 Charger 903 Developing roller (part of transfer means)
904 Toner cartridge 905 Cleaning blade 906 Paper feed tray 907 Paper feed roller 908 Registration roller pair 909 Fixing roller 910 Paper discharge tray 911 Transfer charger (part of transfer means)
912 Paper discharge roller 913 Recording paper 914 Static elimination unit LA Surface emitting laser array VCSEL Surface emitting laser element d1 Space between surface emitting laser elements d2 Positional relationship of surface emitting laser elements

Claims (9)

A surface-emitting laser unit that has a reflecting mirror composed of an AlGaAs high-refractive index layer and a low-refractive index layer having different A1 compositions and an active layer sandwiched between the reflecting mirrors, and that conducts current confinement with a selective oxidation layer. In the element
The wiring for injecting current into the surface emitting laser single element, the wiring width of the mesa side wall connecting the top of the mesa of the surface emitting laser single element, which is a convex portion, to the bottom of the mesa is the concave portion. A surface emitting laser single element characterized in that it is wider than a wiring width formed at the bottom of a mesa. In the surface emitting laser single element according to claim 1,
A wiring for injecting a current into the surface emitting laser single element, and a recess between the bonding pad region of the surface emitting laser single element that is a convex portion and the side wall of the convex portion that connects the mesa bottom portion that is a concave portion. A surface emitting laser single element characterized in that it is wider than a wiring width formed on a mesa bottom. A surface-emitting laser array element that has a reflecting mirror composed of an AlGaAs high-refractive index layer and a low-refractive index layer at least partially different in A1 composition and an active layer sandwiched between the reflecting mirrors, and performs current confinement by a selective oxidation layer In
Wiring for injecting current into the surface emitting laser single element, the wiring width of the mesa side wall connecting the mesa top to the bottom of the mesa of the surface emitting laser single element that is a convex part is formed at the bottom of the mesa that is a concave part A surface emitting laser array element characterized in that the surface emitting laser array element is wider than the formed wiring width. In the surface emitting laser array element according to claim 3,
A surface-emitting laser array element that has a reflecting mirror composed of an AlGaAs high-refractive index layer and a low-refractive index layer at least partially different in A1 composition and an active layer sandwiched between the reflecting mirrors, and performs current confinement by a selective oxidation layer In
The wiring for injecting current into the surface emitting laser array element, the wiring width of the side wall of the convex part connecting the bonding pad region of the surface emitting laser single element that is the convex part and the mesa bottom part that is the concave part, A surface-emitting laser array element characterized in that it is wider than the width of a wiring formed on the bottom of a mesa that is a recess. An optical scanning device that scans a surface to be scanned with a light beam,
A light source unit having the surface emitting laser array element according to claim 1, a deflecting unit for deflecting a light beam from the light source unit, and a surface to be scanned with the deflected light beam. An optical scanning device comprising: a scanning optical system that condenses the light. An optical scanning device that scans a scanning surface with a plurality of light beams,
3. A light source unit having the surface emitting laser array element according to claim 1; deflecting means for deflecting a plurality of light beams from the light source unit; and the deflected light beams. And a scanning optical system for condensing the light on the surface to be scanned. At least one image carrier and at least one optical scanning device according to claim 3 for scanning the at least one image carrier with a light beam including image information;
An image forming apparatus comprising: transfer means for transferring an image formed on the at least one image carrier to a transfer object. 5. The optical scanning device according to claim 4, wherein at least one image carrier, and at least one light scanning device that scans the at least one image carrier with a plurality of light beams including image information;
An image forming apparatus comprising: transfer means for transferring an image formed on the at least one image carrier to a transfer object. A surface-emitting laser array having a reflecting mirror composed of an AlGaAs high-refractive index layer and a low-refractive index layer having different A1 compositions and an active layer sandwiched between the reflecting mirrors and current confinement by a selective oxidation layer In the production method,
an active layer composed of an A1 _0.12 Ga _0.88 As quantum well layer / A _l0.3 Ga _0.7 As obstacle layer on an n-GaAs substrate, an Al _0.6 Ga _0.4 As spacer layer; A resonator region having a thickness of 1 wavelength is composed of 40.5 pairs of n-Al _0.3 Ga _0.7 As high-refractive index layers / n-A _l0.9 Ga with a _{lifespan of} each layer λ / 4. From a lower reflecting mirror composed of a _0.1 As low refractive index layer, and 24 pairs of p-Al _0.3 Ga _0.7 As high refractive index layer / p-Al _0.9 Ga _0.1 As low refractive index layer Form a layer structure sandwiched between upper reflectors,
Next, an AlAs selective oxidation layer is provided on the upper reflecting mirror that is λ / 4 away from the resonator region,
Next, the mesa shape and bonding pad region are simultaneously formed by dry etching,
In that case, the mesa sidewall wiring width connecting the mesa bottom from the mesa top of the surface emitting laser array element which is a convex part is formed wider than the wiring width formed on the mesa bottom part which is a concave part,
Further, the AlAs selectively oxidized layer whose side surface is exposed in the etching process is heat-treated in water vapor, the oxidation proceeds from the mesa end surface, and a current confinement layer that is an Al _x O _y insulator layer is formed.
Subsequently, an interlayer insulating film such as SiO ₂ , SiN, or SiON is formed on the entire surface by plasma CVD,
Further, a method of manufacturing a surface emitting laser array, wherein a contact hole is formed by removing an interlayer insulating layer on an upper reflecting mirror having a p-side electrode contact layer and a light emitting portion by etching.

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