KR20200011190A - A vertical-cavity surface-emitting laser device, a vertical-cavity surface-emitting laser package and light emitting device including the same - Google Patents

Abstract

A surface-emitting laser device capable of minimizing a divergence angle of a laser beam comprises: a first reflective layer; an active layer on the first reflective layer; an oxide layer on the active layer; a second reflective layer on the oxide layer, wherein the second reflective layer includes a plurality of first areas and a second area surrounding the first areas; a plurality of light guide members in contact with the first areas of the second reflective layer; and an electrode on the second area of the second reflective layer. A side of the light guide member may have a ruled surface perpendicular to an upper surface of the second reflective layer.

Description

Surface emitting laser device, surface emitting laser package, and light emitting device including the same {A VERTICAL-CAVITY SURFACE-EMITTING LASER DEVICE, A VERTICAL-CAVITY SURFACE-EMITTING LASER PACKAGE AND LIGHT EMITTING DEVICE INCLUDING THE SAME}

Embodiments relate to a surface emitting laser device, a surface emitting laser package, and a light emitting device including the same.

A semiconductor device including a compound such as GaAs or AlGaAs may emit light of various wavelength bands by using a wide and easy-to-adjust band gap energy, and thus may be variously used as a light emitting device, a light receiving device, and various diodes.

In particular, light emitting devices such as light emitting diodes or laser diodes using group 3-5 or 2-6 compound semiconductor materials have been developed using thin film growth technology and device materials. Various colors such as ultraviolet rays can be realized, and efficient white light can be realized by using fluorescent materials or combining colors.Low power consumption, semi-permanent life, fast response speed, It has the advantages of safety and environmental friendliness.

In addition, when a light receiving device such as a photodetector or a solar cell is manufactured by using a group 3-5 or group 2-6 compound semiconductor material, the development of device materials absorbs light in various wavelength bands, thereby generating a photocurrent. It can receive light in various wavelength bands, ranging from radio wavelength bands. In addition, semiconductor devices have the advantages of fast response speed, safety, environmental friendliness, and easy control of device materials, so that they can be easily adopted in power control or microwave circuits or communication modules.

Therefore, the semiconductor device may replace a transmission / reception module of an optical communication system, a light emitting unit that replaces a cold cathode fluorescent lamp (CCFL) constituting a backlight of a liquid crystal display (LCD), a fluorescent lamp, or an incandescent bulb. Applications are expanding to lighting devices such as white light emitting diodes, automotive headlights, traffic lights or sensors to detect gas or fire.

In addition, the semiconductor device may be extended to high frequency application circuits, other power control devices, and communication modules. For example, there is a surface-emitting laser (VCSEL) device as a semiconductor device. Surface emitting laser devices are used in optical communication, optical parallel processing, optical connection, and the like. On the other hand, the laser diode used in such a communication module is designed to be easy to operate at a low current.

Surface-emitting laser devices are being developed for communication and sensors. The surface emitting laser device for communication is applied to an optical communication system.

The surface emitting laser element for the sensor is applied to a 3D sensing camera that detects a person's face. For example, a 3D sensing camera is a camera capable of capturing depth information of an object, and has recently been in the spotlight in conjunction with augmented reality.

In surface emitting laser devices it is very important to minimize the divergence angel of the laser beam. The divergence angle of the laser beam may be represented by Equation 1 below.

[Equation 1]

Dag = dr / dz

Dag represents the divergence angle of the laser beam, r represents the radius of the laser beam, and z may represent the traveling direction z of the laser beam, that is, the z-axis direction.

From Equation 1, the divergence angle Dag is defined to the extent that the radius of the laser beam (for example, the radius r of the laser beam along the z direction) changes along the traveling direction z of the laser beam. For example, when the increase of the radius r of the laser beam along the advancing direction z of the laser beam is minimized, the divergence angle may also be minimized. Therefore, in order for the surface emitting laser device to be used for a sensor or optical communication, it is very important to minimize the divergence angle of the laser beam.

However, in the conventional surface emitting laser device, it is difficult to optimize the device due to poor design, poor process, and the like in the device such as an opening, and there are many difficulties in minimizing the divergence angle.

The laser beam emitted from the conventional surface emitting laser device has a divergence angle of 20 ° or more, and there is an urgent need for research and development to reduce the divergence angle.

In addition, the laser beam emitted from the conventional surface emitting laser device is emitted at a divergence angle of a predetermined angle or more, thereby reducing output characteristics compared to a minimized laser beam, that is, a focused laser beam.

The embodiment aims to solve the above and other problems.

Another object of the embodiment is to provide a surface emitting laser device having a novel structure, a surface emitting laser package, and a light emitting device including the same.

Another object of the embodiment to provide a surface emitting laser device, a surface emitting laser package and a light emitting device including the same that can minimize the divergence angle of the laser beam.

Still another object of the embodiment is to provide a surface emitting laser device having a high output beam, a surface emitting laser package, and a light emitting device including the same.

According to an aspect of an embodiment to achieve the above or another object, the surface emitting laser device, the first reflective layer; An active layer on the first reflective layer; An oxide layer on the active layer; A second reflective layer on the oxide layer, the second reflective layer including a plurality of first regions and a second region surrounding the first region; A plurality of light guide members in contact with the plurality of first regions of the second reflective layer; And an electrode on the second region of the second reflective layer. The side of the light guide member may have a straight surface perpendicular to the upper surface of the second reflective layer.

According to another aspect of an embodiment, a surface emitting laser package includes a substrate; A surface emitting laser device on the substrate; A housing surrounding the surface emitting laser element; And a diffusion part on the surface light emitting laser device. The surface emitting laser device may include a plurality of light guide members. The side of the light guide member may have a straight surface perpendicular to the upper surface of the second reflective layer, and the light guide member may be disposed adjacent to the diffusion part.

According to another aspect of the embodiment, the light emitting device comprises the surface light emitting laser element.

The effects of the surface emitting laser device, the surface emitting laser package, and the light emitting device including the same according to the embodiment will be described below.

According to at least one of the embodiments, the laser beam is further straightened by the light guide member disposed on the second reflective layer on the active layer such that there is no change in the divergence angle of the laser beam between the second reflective layer and the diffuser. There is an advantage that can be obtained.

According to at least one of the embodiments, by using the optical guide member can provide a laser beam with a minimum divergence angle to the diffuser, it can be widely adopted in applications that require a laser beam having a minimized divergence angle In addition, there is an advantage in that the output characteristic of the laser beam may be prevented from being lowered due to the light loss generated by spreading the laser beam.

According to at least one of the embodiments, the light guide member is attached not only to the upper surface of the first region of the second reflective layer but also to the inclined side surface of the second electrode, thereby increasing the attachment area of the light guide member to prevent the detachment of the light guide member. The advantage is that it can be prevented.

Further scope of the applicability of the embodiments will become apparent from the detailed description below. However, various changes and modifications within the spirit and scope of the embodiments can be clearly understood by those skilled in the art, and therefore, specific embodiments, such as the detailed description and the preferred embodiments, are to be understood as given by way of example only.

1 is a plan view of a surface emitting laser device according to a first embodiment.
FIG. 2 is an enlarged view of one region C1 of the surface emitting laser device according to the first embodiment shown in FIG. 1.
3 is a perspective view of the surface emitting laser device according to the first embodiment.
4A is a first cross-sectional view taken along line A1-A2 of the surface emitting laser device according to the first embodiment shown in FIG. 2.
FIG. 4B is a second cross-sectional view taken along line A3-A4 of the surface emitting laser device according to the first embodiment shown in FIG. 2.
5A and 5B show beam outputs of the surface emitting laser device according to the prior art and the first embodiment.
6 is a cross-sectional view of the surface emitting laser device according to the second embodiment.
7 to 12 illustrate a method of manufacturing a surface emitting laser device according to an embodiment.
13 is a cross-sectional view showing a surface emitting laser package according to the embodiment.
14 is a perspective view of a mobile terminal to which a surface emitting laser device is applied according to an embodiment.

DETAILED DESCRIPTION Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

In the description of the embodiments, when described as being formed on the "on or under" of each element, the on or under is It includes both the two elements are in direct contact with each other (directly) or one or more other elements are formed indirectly between the two (element). In addition, when expressed as "on" or "under", it may include the meaning of the downward direction as well as the upward direction based on one element.

(First embodiment)

1 is a plan view of a surface light emitting laser device according to a first embodiment, and FIG. 2 is an enlarged view of one region C1 of the surface light emitting laser device according to the first embodiment shown in FIG. 1. 3 is a perspective view of the surface emitting laser device according to the first embodiment. 4A is a first cross-sectional view taken along line A1-A2 of the surface emitting laser device according to the first embodiment shown in FIG. 2, and FIG. 4B is A3 of the surface emitting laser device according to the first embodiment shown in FIG. Second section along the line A4.

1 to 4B, the surface emitting laser device 201 according to the first embodiment may include a light emitting part E and a pad part P. FIG. As shown in FIG. 2, the light emitting unit E may be a region including a plurality of light emitting emitters E1, E2, and E3, and may emit a laser beam. For example, the light emitting unit E may include tens to hundreds of light emitting emitters. The pad part P may be a region that is not disposed in the light emitting emitters E1, E2, and E3.

The surface emitting laser device 201 according to the first embodiment may include a second electrode 282 defining an opening. That is, in each emission emitter E1, E2, or E3, the second electrode 282 may be disposed in the remaining regions except for the region corresponding to the opening 241. For example, the second electrode 282 may be disposed in the second region of the second reflective layer 250. The first region of the second reflective layer 250 is surrounded by the second region and may be equal to or larger than the size of the opening 241. Therefore, the beam generated in the emission layer 230 may pass through the opening 241 and be emitted to the outside through the opening defined by the second electrode 282.

The surface emitting laser device 201 according to the first embodiment includes a first electrode 215, a substrate 210, a first reflective layer 220, a light emitting layer 230, an oxide layer 240, a second reflective layer 250, One or more of the passivation layer 270 and the second electrode 282 may be included.

The oxide layer 240 may include an opening 241 and an insulating region 242. The opening 241 may be a passage area through which current flows. The insulating region 242 may be a blocking region that blocks the flow of current. The insulating region 242 may be referred to as an oxide layer or an oxide layer.

The oxide layer 240 may be referred to as a current confinement layer because it restricts the flow or density of the current to emit a more coherent laser beam.

The surface emitting laser device 201 according to the first embodiment may further include a pad electrode 280. The pad electrode 280 may be disposed in an area excluding the pad part P, that is, the light emitting part E. FIG. The pad electrode 280 may be electrically connected to the second electrode 282. The first electrode 282 and the pad electrode 280 may be formed integrally or separately.

Hereinafter, technical features of the surface emitting laser device 201 according to the first embodiment will be described with reference to FIGS. 1 to 4B. In the drawings of the embodiment, the direction of the x-axis may be a direction parallel to the longitudinal direction of the substrate 210, the y-axis may be a direction perpendicular to the x-axis.

<Substrate, first electrode>

The surface emitting laser device 201 according to the first embodiment provides a substrate 210. The substrate 210 may be a conductive substrate or a nonconductive substrate. As the conductive substrate, a metal having excellent electrical conductivity may be used. Since the heat generated during the operation of the surface emitting laser device 201 should be sufficiently dissipated, a GaAs substrate or a metal substrate having high thermal conductivity or a silicon (Si) substrate may be used as the conductive substrate. As the non-conductive substrate, an AlN substrate, a sapphire (Al ₂ O ₃ ) substrate, or a ceramic-based substrate may be used.

The surface emitting laser device 201 according to the first embodiment provides a first electrode 215. The first electrode 215 may be disposed under the substrate 210. The first electrode 215 may be disposed in a single layer or multiple layers of a conductive material. For example, the first electrode 215 may be a metal and include at least one of aluminum (Al), titanium (Ti), chromium (Cr), nickel (Ni), copper (Cu), and gold (Au). Therefore, it is formed in a single layer or a multi-layer structure, it is possible to improve the electrical characteristics to increase the light output.

<1st reflective layer>

The surface emitting laser device 201 according to the first embodiment provides a first reflective layer 220. The first reflective layer 220 may be disposed on the substrate 210. When the substrate 210 is omitted to reduce the thickness, the bottom surface of the first reflective layer 220 may contact the top surface of the first electrode 215.

The first reflective layer 220 may be doped with a first conductivity type dopant. For example, the first conductivity type dopant may include an n type dopant such as Si, Ge, Sn, Se, Te, or the like.

The first reflective layer 220 may include a gallium-based compound, for example, AlGaAs, but is not limited thereto. The first reflective layer 220 may be a distributed bragg reflector (DBR). For example, the first reflective layer 220 may have a structure in which a first layer and a second layer including materials having different refractive indices are alternately stacked at least once.

For example, the first reflective layer 220 may include a plurality of layers disposed on the substrate 210. Each layer may include a semiconductor material having a compositional formula of Al _x Ga _(1-x) As (0 <x <1), and as the Al in each layer increases, the refractive index of each layer decreases, and if Ga increases The refractive index of each layer can increase. The thickness of each layer may be λ / 4n, λ may be the wavelength of light generated in the light emitting layer 230, and n may be the refractive index of each layer for light of the above-described wavelength. Here, λ may be 650 to 980 nanometers (nm), and n may be the refractive index of each layer. The first reflective layer 220 having such a structure may have a reflectance of 99.999% for light having a wavelength of about 940 nanometers.

The thickness of the layer in each first reflective layer 220 may be determined according to the refractive index and the wavelength λ of the light emitted from the light emitting layer 230.

<Light emitting layer>

The surface emitting laser device 201 according to the first embodiment may include a light emitting layer 230. The light emitting layer 230 may be disposed on the first reflective layer 220. In detail, the emission layer 230 may be disposed on the first reflective layer 220. The light emitting layer 230 may be disposed between the first reflective layer 220 and the second reflective layer 250.

The light emitting layer 230 may include an active layer and at least one cavity. For example, the emission layer 230 may include an active layer, a first cavity disposed below the active layer, and a second cavity disposed above the active layer. The light emitting layer 230 of the embodiment may include both the first cavity and the second cavity, or may include only one of them.

The active layer may include any one of a single well structure, a multi well structure, a single quantum well structure, a multi quantum well (MQW) structure, a quantum dot structure, and a quantum line structure.

The active layer may include a quantum well layer and a quantum wall layer using a group 3-5 or group 2-6 compound semiconductor material. The quantum well layer may be formed of a material having an energy band gap smaller than the energy band gap of the quantum wall layer. The active layer may be formed of one to three pair structures such as InGaAs / AlxGaAs, AlGaInP / GaInP, AlGaAs / AlGaAs, AlGaAs / GaAs, GaAs / InGaAs, but is not limited thereto. The dopant may not be doped in the active layer.

The first cavity and the second cavity may be formed of Al _y Ga _(1-y) As (0 <y <1) material, but are not limited thereto. For example, the first cavity and the second cavity may each include a plurality of layers of Al _y Ga _(1-y) As.

<Oxide layer>

The surface emitting laser device 201 according to the first embodiment may provide the oxide layer 240. The oxide layer 240 may include an insulating region 242 and an opening 241. The insulating region 242 may surround the opening 241. For example, the opening 241 may be disposed on the first area (center area) of the light emitting layer 230, and the insulating area 242 may be disposed on the second area (edge area) of the light emitting layer 230. The second region may surround the first region.

The opening 241 may be a passage area through which current flows. The insulating region 242 may be a blocking region that blocks the flow of current. The insulating region 242 may be referred to as an oxide layer or an oxide layer.

The amount of current supplied from the second electrode 282 to the light emitting layer 230, that is, the current density may be determined by the size of the opening 241. The size of the opening 241 may be determined by the insulating region 242. As the size of the insulating region 242 increases, the size of the opening 241 may decrease, and thus the current density supplied to the light emitting layer 230 may increase. In addition, the opening 241 may be a passage through which the beam generated in the emission layer 230 travels in an upward direction, that is, in a direction of the second reflective layer 250. That is, the divergence angle of the beam of the light emitting layer 230 may vary according to the size of the opening 241.

The insulating region 242 may be formed of an insulating layer, for example, aluminum oxide (Al ₂ O ₃ ). For example, when the oxide layer 240 includes aluminum gallium arsenide (AlGaAs), the AlGaAs of the oxide layer 240 reacts with H ₂ O to change the edge to aluminum oxide (Al ₂ O ₃ ), thereby insulating the region 242. The central region, which is formed of H ₂ O and does not react with H ₂ O, may be an opening 241 including AlGaAs.

According to the embodiment, the light emitted from the light emitting layer 230 through the opening 241 may be emitted to the upper region, and the light transmittance of the opening 241 may be excellent compared to the insulating region 242.

The insulating region 242 may include a plurality of layers. For example, the insulating region 242 may be disposed between the first insulating region, the second insulating region disposed on the first insulating region, and the second insulating region. It may include a third insulating region. One insulating region of the first to third insulating regions may have the same thickness as the other insulating region or may have a different thickness. The first to third insulating regions may include at least an oxidation material. The first to third insulating regions may include at least a group 3-5 or a group 2-6 compound semiconductor material.

<Second reflective layer>

The surface emitting laser device 201 according to the first embodiment may include a second reflective layer 250. The second reflective layer 250 may be disposed on the oxide layer 240.

The second reflective layer 250 may include a gallium-based compound, for example, AlGaAs, and the second reflective layer 250 may be doped with a second conductive dopant. The second conductivity type dopant may be a p-type dopant such as Mg, Zn, Ca, Sr, Ba, or the like. Meanwhile, the first reflective layer 220 may be doped with a p-type dopant, and the second reflective layer 250 may be doped with an n-type dopant.

The second reflecting layer 250 may also be a distributed Bragg reflector (DBR). For example, the second reflective layer 250 may have a structure in which a plurality of layers including materials having different refractive indices are alternately stacked at least once.

Each layer of the second reflective layer 250 may include AlGaAs, and in detail, may be formed of a semiconductor material having a compositional formula of Al _x Ga _(1-x) As (0 <x <1). Herein, when Al increases, the refractive index of each layer may decrease, and when Ga increases, the refractive index of each layer may increase. Each layer of the second reflective layer 250 may have a thickness of λ / 4n, λ may be a wavelength of light emitted from the active layer, and n may be a refractive index of each layer with respect to light having the aforementioned wavelength.

The second reflective layer 250 having such a structure may have a reflectance of 99.9% for light having a wavelength of about 940 nanometers.

The second reflective layer 250 may be formed by alternately stacking layers, and the number of pairs of layers in the first reflective layer 220 may be greater than the number of pairs of layers in the second reflective layer 250. . As described above, the reflectance of the first reflective layer 220 may be 99.999%, which may be greater than 99.9% of the reflectance of the second reflective layer 250.

In the first embodiment, the second reflective layer 250 may include a plurality of layers disposed on the light emitting layer 230. Each layer may be formed of a single or a plurality of layers.

Passivation layer, second electrode

The surface emitting laser device 201 according to the first embodiment may provide a passivation layer 270. The passivation layer 270 may surround a portion of the light emitting structure. Some regions of the light emitting structure may include, for example, the light emitting layer 230, the oxide layer 240, and the second reflective layer 250. The passivation layer 270 may be disposed on the top surface of the first reflective layer 220. The passivation layer 270 may be disposed on an edge region of the second reflective layer 250. When the light emitting structure is partially mesa-etched, a portion of the upper surface of the first reflective layer 220 may be exposed, and a portion of the light emitting structure may be formed. The passivation layer 270 may be disposed on a circumference of a portion of the light emitting structure and on an upper surface of the exposed first reflective layer 220.

The passivation layer 270 may protect the light emitting structure from the outside and block electrical short between the first reflective layer 220 and the second reflective layer 250. The passivation layer 270 may be formed of an inorganic material such as SiO ₂ , but is not limited thereto.

The surface emitting laser device 201 according to the first embodiment may provide the second electrode 282. The second electrode 282 may be electrically connected to the pad electrode 280. The second electrode 282 may contact a portion of the top surface of the second reflective layer 250.

The second electrode 282 and the pad electrode 280 may be made of a conductive material. For example, the second electrode 282 and the pad electrode 280 may include platinum (Pt), aluminum (Al), titanium (Ti), chromium (Cr), nickel (Ni), tungsten (W), and copper (Cu). ), Gold (Au) may be formed in a single layer or a multi-layer structure.

<Optical guide member>

The surface emitting laser device 201 according to the first embodiment may provide the light guide member 310. For example, the light guide member 310 may be included in the surface emitting laser device 201. For example, the light guide member 310 may not be included in the surface emitting laser device 201 but may be configured separately.

The light guide member 310 may serve to guide the laser beam emitted from the active layer of the surface emitting laser device 201 according to the first embodiment to minimize the divergence angle of the laser beam.

As will be described later, when the surface light emitting laser device 201 according to the first embodiment is adopted in the surface light emitting laser package 400 of FIG. 13, the diffusion portion 440 may be disposed on the surface light emitting laser device 201. Can be. In this case, the light guide member 310 may serve to deliver the laser beam emitted from the active layer of the surface emitting laser device 201 to the diffuser 440 with a minimum.

The divergence angle of the laser beam is not increased from the second reflecting layer 250 of the surface emitting laser element 201 to the diffusion portion 440, and is not increased from the second reflecting layer 250 of the surface emitting laser element 201. The divergence angle of the laser beam on the upper surface may be maintained as it is adjacent to the diffuser 440. That is, the divergence angle of the laser beam in the second reflective layer 250 of the surface emitting laser device 201 and the divergence angle of the laser beam at a position (or region) adjacent to the diffusion part 440 may be the same.

For example, the lower surface of the light guide member 310 is in contact with the upper surface of the second reflective layer 250 of the surface light emitting laser element 201, the upper surface of the light guide member 310 is a predetermined distance from the lower surface of the diffuser 440. It may be spaced apart. The predetermined distance may be, for example, 0.5 times or less of the height of the light guide member 310. In this case, the lower surface of the light guide member 310 may be fixed to the upper surface of the second reflective layer 250.

For example, the lower surface of the light guide member 310 is in contact with the upper surface of the second reflective layer 250 of the surface light emitting laser element 201, and the upper surface of the light guide member 310 is in contact with the lower surface of the diffuser 440. Can be.

According to the first embodiment, the laser beam having a more straightness can be obtained by not changing the divergence angle of the laser beam between the second reflective layer 250 and the diffusion portion 440 by the light guide member 310. have.

According to the first embodiment, by minimizing the divergence angle of the laser beam between the second reflective layer 250 and the diffusion portion 440 by the light guide member 310, the laser beam due to the light loss generated by the laser beam spread It is possible to prevent the deterioration of the output characteristics.

1 to 3, a pad electrode 280 is disposed in the pad portion P, and each emitter E1, E2, E3 has a second region surrounding a first region (center region). The second electrode 282 may be disposed in the (edge region). The second reflective layer 250 may be exposed to the outside without the second electrode 282 disposed in the first region. The laser beam may be emitted upward through the first region of each emitter E1, E2, E3.

According to the first embodiment, the light guide member 310 may be disposed in each emitter (E1, E2, E3). Specifically, the light guide member 310 may be disposed on the second reflective layer 250 corresponding to the first region in each emitter E1, E2, or E3. The light guide members 310 disposed in the adjacent emitters E1, E2, and E3 may be spaced apart from each other. The separation distance of the light guide member 310 may vary depending on, for example, the distance between the center point of the first area of each emitter E1, E2, E3 and the radius of the first area of each emitter E1, E2, E3. have. For example, as the distance between the center points of the first regions of the emitters E1, E2, and E3 is closer and the radius is smaller, the separation distance between the light guide members 310 may be larger.

For convenience, it is described that one light guide member 310 is disposed on the first area of each emitter E1, E2, E3. However, two light guide members 310 are disposed on the first area of each emitter E1, E2, E3. More than one light guide member 310 may be disposed.

As shown in FIGS. 4A and 4B, the second reflective layer 250 may have a first region and a second region surrounding the first region. The second electrode 282 may be disposed on the second region of the second reflective layer 250.

The light guide member 310 may be disposed on the first region of the second reflective layer 250. For example, the light guide member 310 may contact the top surface of the first region of the second reflective layer 250.

The light guide member 310 may vary depending on the shape of the first region of the second reflective layer 250. When viewed from above, for example, when the first region of the second reflective layer 250 is circular, the light guide member 310 may also be circular, but is not limited thereto. In this case, the light guide member 310 may have a cylindrical three-dimensional shape. That is, each of the lower surface (incident surface) and the upper surface (emission surface) of the light guide member 310 may have a flat surface, and the side surface of the light guide member 310 may have a round shape. For example, the side surface of the light guide member 310 may have a straight surface perpendicular to the top surface of the second reflective layer 250. That is, the side surface of the light guide member 310 may have a straight surface in the upper direction from the upper surface of the second reflective layer 250. The side surface of the incident surface of the light guide member 310 also has a straight surface perpendicular to the top surface of the second reflective layer 250, and the side surface of the exit surface of the optical guide member 310 is also perpendicular to the upper surface of the second reflective layer 250. It may have a straight surface.

The lower surface of the light guide member 310 is an area in contact with the second reflective layer 250, and the upper surface may extend from the lower surface to be away from the upper surface of the second reflective layer 250. In this case, the entrance face and the exit face may have the same diameter D1. The incident surface may be an incident surface to which a laser beam generated in the active layer is incident, and the exit surface may be an exit surface from which the laser beam is emitted.

The emission surface of the light guide member 310 may be spaced apart from the lower surface of the diffusion portion 440 of FIG. 13. As another example, the exit surface of the light guide member 310 may be in contact with the bottom surface of the diffusion portion 440 of FIG. 13.

The light guide member 310 may include a transparent material so that laser light can be easily transmitted.

The light guide member 310 may be formed of a material capable of total reflection of the light emitted from the active layer. Since the light guide member 310 is exposed to air, the light guide member 310 may be formed of a semiconductor material having a refractive index larger than that of air.

The refractive index of the light guide member 310 may be the same as or similar to the refractive index of the second reflective layer 250 in order to transfer the laser beam from the second reflective layer 250 to the light guide member 310. For example, the ratio of the refractive index of the second reflective layer 250 and the refractive index of the light guide member 310 may be about 1: 0.95 to about 1: 1.1. For example, when the second reflective layer 250 includes GaAs, the refractive index of the second reflective layer 250 may be 1.95. For example, when the light guide member 310 includes ZnO, the refractive index of the light guide member 310 may be 1.9. Therefore, since the light guide member 310 is formed of a material having the same or similar refractive index as that of the second reflective layer 250, the laser beam generated in the active layer is passed through the second reflective layer 250. It can be delivered well to minimize light loss.

The light guide member 310 may be formed of a semiconductor material which may have a critical angle capable of total reflection. For example, the light guide member 310 may include zinc oxide (ZnO), but is not limited thereto. For example, the critical angle may be at least 27 degrees. For example, the critical angle may be approximately 30.9 °, but is not limited thereto.

Since the refractive index of the light guide member 310 has a 1.9 that is larger than that of air, the laser beam is totally reflected by the light guide member 310 so that the light guide member 310 leaves the light guide member 310 and does not proceed to air. The angle may be transmitted to the diffusion part 440 of FIG. 13 while being maintained in the entire area of the light guide member 310.

The height T of the light guide member 310 may be larger than the diameter D of the light guide member 310. For example, the ratio of the diameter of the light guide member 310 and the height of the light guide member 310 may be about 1: 6.7 to about 1: 100. For example, the light guide member 310 may have a diameter of about 5㎛ to about 15㎛. For example, the light guide member 310 may have a diameter of about 5㎛ to about 10㎛. For example, the light guide member 310 may have a height of about 100 μm to about 500 μm. For example, the light guide member 310 may have a height of about 100 μm to about 300 μm.

In this way, by increasing the height than the diameter of the light guide member 310, it can be made to proceed to the total reflection of the laser beam.

The light guide member 310 may have a diameter at least greater than the diameter of the opening 241 of the oxide layer 240. For example, the light guide member 310 may have a diameter of about 0.5 μm to about 3 μm larger than the diameter of the opening 241 of the oxide layer 240. For example, the light guide member 310 may have a diameter of about 0.5 μm to about 2 μm larger than the diameter of the opening 241 of the oxide layer 240.

5A and 5B show beam outputs of the surface emitting laser device according to the prior art and the first embodiment.

As shown in FIG. 5A, conventionally, the surface emitting laser device 100 and the diffusion part 120 are spaced apart, so that the laser beam emitted from the surface emitting laser device 100 proceeds to the diffusion 120 part. As the beam spreads, the divergence angle can be increased.

As shown in FIG. 5B, in the surface light emitting laser device 201 according to the first embodiment, since the light guide member 310 is in contact with the diffuser 440 or the position adjacent to the diffuser 440, the surface luminescent laser device 201 is used. Since the light emitted from the laser device 201 is totally reflected by the light guide member 310 and proceeds to enter the pattern 445 of the diffusion part 440, the divergence angle of the laser beam passing through the light guide member 310 is maintained as it is. It may be incident to the diffusion portion 440 while being maintained.

Therefore, since the incident angle of the light guide member 310 in contact with the second reflective layer 250 of the surface light emitting laser element 201 and the emission angle of the light exiting surface of the optical guide member 310 are the same, the second reflective layer ( A laser beam equal to the size of the first region of 250 may be transmitted to the diffuser 440 as it is. Even if the emission surface of the light guide member 310 is spaced apart from the diffusion portion 440, the divergence angle of the laser beam is hardly increased, and thus the degree of increase of the divergence angle may be ignored.

According to the first exemplary embodiment, the light guide member 310 may be used to provide a laser beam having a minimized divergence angle to the diffusion unit 440, so that a laser beam having a minimized divergence angle is required. It can be widely adopted, and the degradation of the output characteristics of the laser beam due to the light loss generated by spreading the laser beam can be prevented.

(2nd Example)

6 is a cross-sectional view of the surface emitting laser device according to the second embodiment.

The second embodiment is the same as the first embodiment except for the light guide member 310. In the second embodiment, components having the same function, shape, or structure as those of the first embodiment will be denoted by the same reference numerals and detailed description thereof will be omitted.

In the following, description of components having the same function, shape, and structure as in the first embodiment will be omitted in order to avoid duplication of description.

Referring to FIG. 6, the surface emitting laser device 201A according to the second embodiment may provide a second reflective layer 250.

The second reflective layer 250 may include a first region and a second region surrounding the first region. In this case, a second electrode 282 electrically connected to the pad electrode 280 may be disposed on the second region of the second reflective layer 250. That is, it may be in contact with the top surface of the second region of the second reflective layer 250 of the partial region of the second electrode 282. The second electrode 282 is not disposed on the first region of the second reflective layer 250.

Due to the thickness or forming process of the second electrode 282, an end of the second electrode 282 in contact with the first region of the second reflective layer 250 may have an inclined side surface 285. The angle of the inclined side surface 285 may vary depending on the thickness or forming process of the second electrode 282.

As another example, an end of the second electrode 282 may have a side surface perpendicular to the second reflective layer 250, but is not limited thereto.

The surface emitting laser device 201A according to the second embodiment may provide the light guide member 310.

The incident surface of the light guide member 310 may contact the upper surface of the first region of the second reflective layer 250. A portion of the side surface of the light guide member 310 may contact the inner side surface of the second electrode 282, that is, the inclined side surface 285.

According to the second embodiment, since the light guide member 310 is attached not only to the upper surface of the first region of the second reflective layer 250 but also to the inclined side surface of the second electrode 282, the light guide member 310 is attached. The area of the light guide member 310 can be prevented from increasing by increasing the area.

(Manufacturing method)

Hereinafter, a method of manufacturing the surface emitting laser device according to the embodiment will be described with reference to FIGS. 7 to 12. On the other hand, the following manufacturing method can be applied to the manufacturing method of the surface emitting laser device 201, 201A according to the first and second embodiments.

First, as shown in FIG. 7, a light emitting structure including a first reflective layer 220, a light emitting layer 230, and a second reflective layer 250 is formed on a substrate 210.

The substrate 210 may be formed of a material suitable for growth of a semiconductor material or a carrier wafer, may be formed of a material having excellent thermal conductivity, and may include a conductive substrate or an insulating substrate.

For example, when the substrate 210 is a conductive substrate, a metal having excellent electrical conductivity may be used, and GaAs having high thermal conductivity may be used because it must be able to sufficiently dissipate heat generated when the surface emitting laser devices 201 and 201A operate. A substrate, a metal substrate, or a silicon (Si) substrate may be used.

In addition, when the substrate 210 is a non-conductive substrate, an AlN substrate, a sapphire (Al ₂ O ₃ ) substrate, or a ceramic substrate may be used.

In addition, in the exemplary embodiment, a substrate of the same type as the first reflective layer 220 may be used as the substrate 210. For example, when the substrate 210 is a GaAs substrate of the same type as the first reflective layer 220, the lattice constant coincides with the first reflective layer 210, so that a defect such as lattice mismatch does not occur in the first reflective layer 220. Can be.

Next, the first reflective layer 220 may be formed on the substrate 210.

The first reflective layer 220 may be grown using a chemical vapor deposition method (CVD) or a molecular beam epitaxy (MBE) or a sputtering or hydroxide vapor phase epitaxy (HVPE).

The first reflective layer 220 may be doped with a first conductivity type. For example, the first conductivity type dopant may include an n type dopant such as Si, Ge, Sn, Se, Te, or the like.

The first reflective layer 220 may include a gallium-based compound, for example, AlGaAs, but is not limited thereto. The first reflecting layer 220 may be a distributed bragg reflector (DBR). For example, the first reflective layer 220 may have a structure in which layers including materials having different refractive indices are alternately stacked at least once.

For example, as shown in FIG. 7, the first reflective layer 220 is the first group first reflective layer 221 disposed on the substrate 210 and the second group disposed on the first group first reflective layer 221. It may include a first reflective layer 222.

The first group first reflecting layer 221 and the second group first reflecting layer 222 include a plurality of layers including a semiconductor material having a compositional formula of Al _x Ga _(1-x) As (0 <x <1). If the Al in each layer increases, the refractive index of each layer may decrease, and if Ga increases, the refractive index of each layer may increase.

In addition, as shown in FIG. 7, the first group first reflective layer 221 and the second group first reflective layer 222 may also be formed of a single layer or a plurality of layers, respectively. For example, the first group first reflective layer 221 may include about 30-40 pairs of the first group first-first layer 221a and the first group first-second layer 221b. have. In addition, the second group first reflective layer 222 may also include about 5 to 15 pairs of the second group first-first layer 222a and the second group first-second layer 222b.

Next, the light emitting layer 230 may be formed on the first reflective layer 220.

As illustrated in FIG. 7, the emission layer 230 may include an active layer 232, a first cavity 231 disposed under the active layer 232, and a second cavity 233 disposed above the active layer 232. The light emitting layer 230 of the embodiment may include both the first cavity 231 and the second cavity 233, or may include only one of the two.

 The active layer 232 may include a quantum well layer 232a and a quantum wall layer 232b using a compound semiconductor material of group III-V elements. The active layer 232 may be formed in a 1 to 3 pair structure such as InGaAs / AlxGaAs, AlGaInP / GaInP, AlGaAs / AlGaAs, AlGaAs / GaAs, GaAs / InGaAs, but is not limited thereto. Dopants may not be doped in the active layer 232.

The first cavity 231 and the second cavity 233 may be formed of Al _y Ga _(1-y) As (0 <y <1) material, but are not limited thereto. For example, the first cavity 231 and the second cavity 233 may each include a plurality of layers made of Al _y Ga _(1-y) As.

For example, the first cavity 231 may include a first-first cavity layer 231a and a first-second cavity layer 231b. In addition, the second cavity 233 may include a 2-1 cavity layer 233a and a 2-2 cavity layer 233b.

Next, a plurality of semiconductor films 240a, 240b, and 240c for forming the oxide layer 240 may be formed on the emission layer 230. The semiconductor layers 240a, 240b, and 240c may include an AlGa-based material.

Next, a second reflective layer 250 may be formed on the semiconductor film 240c.

The second reflective layer 250 may include a gallium-based compound, for example AlGaAs. For example, each layer of the second reflective layer 250 may include AlGaAs, and in detail, may be formed of a semiconductor material having a compositional formula of Al _x Ga _(1-x) As (0 <x <1). .

The second reflective layer 250 may be doped with a second conductivity type dopant. For example, the second conductivity type dopant may be a p-type dopant such as Mg, Zn, Ca, Sr, Ba, or the like. Meanwhile, the first reflective layer 220 may be doped with a p-type dopant, and the second reflective layer 250 may be doped with an n-type dopant.

The second reflecting layer 250 may also be a distributed Bragg reflector (DBR). For example, the second reflective layer 250 may have a structure in which a plurality of layers including materials having different refractive indices are alternately stacked at least one or more times.

For example, the second reflective layer 250 may be disposed to be spaced apart from the first group second reflective layer 251 and the first group second reflective layer 251 disposed adjacent to the light emitting layer 230. The group second reflective layer 252 may be included.

In addition, the first group second reflection layer 251 and the second group second reflection layer 252 may also be formed of a single layer or a plurality of layers, respectively. For example, the first group second reflective layer 251 may include about 1 to 5 pairs of the first group 2-1 layer 251a and the first group 2-2 layer 251b. In addition, the second group second reflective layer 252 may also include about 5 to 15 pairs of the second group 2-1 layer 252a and the second group 2-2 layer 252b. .

Next, FIG. 8A is an enlarged view of a region C1 of the surface light emitting laser device according to the embodiment, and FIG. 8B is a cross-sectional view taken along line A1-A2 of the surface light emitting laser device according to the embodiment shown in FIG. 8A.

8B, the light emitting structure may be etched using a predetermined mask 300 to form the mesa region M. Referring to FIG. In this case, the mesa may be etched from the second reflective layer 250 to the oxide layer 240 and the light emitting layer 230, and may be mesa etched to a part of the first reflective layer 220. In mesa etching, the oxide layer 240 and the light emitting layer 230 may be removed from the second reflective layer 250 in the peripheral region by an inductively-coupled plasma (ICP) etching method, and the mesa etching region may be etched with the inclined side. Can be. By such mesa etching, the light emitting structures of the light emitting emitters E1, E2, and E3 may be formed.

 Next, FIG. 9A is an enlarged view of a region C1 of the surface light emitting laser device according to the embodiment, and FIG. 9B is a cross-sectional view taken along line A1-A2 of the surface light emitting laser device according to the embodiment shown in FIG. 9A.

In an embodiment, as illustrated in FIG. 9B, an insulating region 242 including first to third insulating regions changed in response to H ₂ O in a plurality of semiconductor films 240a, 240b, and 240c of the oxide layer 240 by a wet oxidation process. ) And an opening 241 including first to third semiconductor regions that do not react with H ₂ O and include a semiconductor material as it is. Insulating region 242 is included in the semiconductor films 240a, 240b, and 240c of the oxide layer 240 by H ₂ O penetrating therein from the outer surfaces of the plurality of semiconductor films 240a, 240b, and 240c of the oxide layer 240. It may include a modified aluminum oxide (Al ₂ O ₃ ) by reacting with the Al. Opening H ₂ O is an area that can not be penetrated into the interior of the plurality of semiconductor films (240a, 240b, 240c) of the oxide layer (240), H ₂ O is not react with Al, so a semiconductor material, that is AlGa-based material can do.

In addition, the embodiment may change the edge region of the AlGa series layer into the insulating region 242 through ion implantation, but is not limited thereto. During ion implantation, photons may be supplied with energy of 300 keV or more.

After the reaction process described above, a conductive opening 241 may be disposed in the central region of the oxide layer 240, and a non-conductive insulating region 242 may be disposed in the edge region.

Next, FIG. 10A is an enlarged view of a region C1 of the surface light emitting laser device according to the embodiment, and FIG. 10B is a cross-sectional view taken along line A1-A2 of the surface light emitting laser device according to the embodiment shown in FIG. 10A.

As shown in FIG. 10B, a passivation layer 270 may be formed on an upper surface of the light emitting structure. The passivation layer 270 may include at least one of polymide, silica (SiO ₂ ), or silicon nitride (Si ₃ N ₄ ).

The passivation layer 270 may expose a portion of the second reflective layer 250 to be electrically connected to the second electrode 282 formed thereafter.

Next, FIG. 11A is an enlarged view of a first region portion C1 of the surface light emitting laser device according to the embodiment, and FIG. 11B is a cross-sectional view along the lines A1-A2 of the surface light emitting laser device according to the embodiment shown in FIG. 11A. .

In example embodiments, the second electrode 282 may be formed on the second reflective layer 250. A pad electrode 280 electrically connected to the second electrode 282 may also be formed. The pad electrode 280 may be formed between each emitter E1, E2, E3. The pad electrode 280 may be formed on the passivation layer 270.

For example, the second electrode 282 may be formed only in a portion of the second reflective layer 250. For example, the second reflective layer 250 may have a first region and a second region surrounding the first region. In this case, the second electrode 282 may be formed on the second region of the second reflective layer 250. Since the second electrode 282 is not formed in the first region of the second reflective layer 250, the first region of the second reflective layer 250 may be exposed to the outside. The first region of the second reflective layer 250 may have a size larger than the size of the opening 241 of the oxide layer 240.

The second electrode 282 and the pad electrode 280 may be made of a conductive material. For example, the second electrode 282 and the pad electrode 280 may include at least one of aluminum (Al), titanium (Ti), chromium (Cr), nickel (Ni), copper (Cu), and gold (Au). It may be formed in a single layer or a multi-layer structure.

Next, the first electrode 215 may be disposed under the substrate 210. Before disposing the first electrode 215, a portion of the bottom surface of the substrate 210 may be removed through a predetermined grinding process to improve heat dissipation efficiency. The first electrode 215 may be made of a conductive material, for example, metal. For example, the first electrode 215 may include at least one of aluminum (Al), titanium (Ti), chromium (Cr), nickel (Ni), copper (Cu), and gold (Au). It can be formed as.

Meanwhile, the seed layer 310a may be formed on the first region of the second reflective layer 250. The seed layer 310 may serve as a seed for easily growing the optical guide member 310 (FIG. 12) to be formed later.

12 is a cross-sectional view of the surface emitting laser device according to the embodiment.

The light guide member 310 may be grown using the seed layer 310 as a seed. The light guide member 310 may be deposited on the seed layer 310 using deposition equipment such as MOCVD.

The light guide member 310 may be formed of the same material as the seed layer 310, but is not limited thereto. For example, the light guide member 310 may include ZnO.

Although one light guide member 310 is formed in FIG. 12 for convenience of description, a plurality of light guide members 310 may be formed on the second reflective layer 250 of the surface emitting laser device 201. .

The semiconductor device including the surface-emitting laser device described above may be a laser diode, and the two reflective layers may act as a resonator. At this time, holes and a second carrier, that is, electrons, are supplied to the active layer from the first reflective layer 220 of the first conductivity type and the second reflective layer 250 of the second conductivity type, and the light emitted from the emission layer 230 is resonator. When reflected and amplified therein and reaches a threshold current, the light may be emitted to the outside through the opening 241 described above.

The light emitted from the surface emitting laser device according to the embodiment may be light of a single wavelength and a single phase, and a single wavelength region may vary according to the composition of the first reflective layer 220, the second reflective layer 250, and the light emitting layer 230. Can be.

Surface Emitting Laser Package

13 is a cross-sectional view showing a surface emitting laser package according to the embodiment.

Referring to FIG. 13, the surface emitting laser package 400 according to the embodiment may provide a substrate 410.

Substrate 410 may support all components disposed on substrate 410. For example, the substrate 410 may support the surface emitting laser device 201, the housing 430, and the diffuser 440 disposed thereon. The surface emitting laser device 201, the housing 430, the diffuser 440, and the substrate 410 may be modular modules. One or more such modules may be mounted on the circuit board 460.

 The substrate 410 may include a material having high thermal conductivity. The substrate 410 may be made of a material having a good heat dissipation property so as to efficiently discharge heat generated from the surface emitting laser device 201 to the outside. The substrate 410 may include an insulating material.

For example, the substrate 410 may include a ceramic material. The substrate 410 may include a low temperature co-fired ceramic (LTCC) or a high temperature co-fired ceramic (HTCC) that is co-fired.

In addition, the substrate 410 may include a metal compound. The substrate 410 may include a metal oxide having a thermal conductivity of 140 W / mK or more. For example, the substrate 410 may include aluminum nitride (AlN) or alumina (Al 2 O 3).

As another example, the substrate 410 may include a resin-based insulating material. The substrate 410 may be made of a silicone resin, an epoxy resin, a thermosetting resin including a plastic material, or a high heat resistant material.

The substrate 410 may include a conductive material. When the substrate 410 is made of a conductive material, such as a metal, an insulating layer 27 for electrical insulation between the substrate 410 and the surface emitting laser element 201 may be provided.

The surface emitting laser package 400 according to the embodiment may provide the surface emitting laser device 201.

The surface emitting laser device 201 may be disposed on the substrate 410. The surface emitting laser device 201 may generate a laser beam and emit the laser beam in a direction perpendicular to the upper surface of the surface emitting laser device 201.

An optical guide member 310 may be disposed above the surface emitting laser device to guide the laser beam using total reflection.

The surface emitting laser device 201 may advance a laser beam having a diverging angle of, for example, 15 ° to 25 ° by the light guide member 310. The surface emitting laser device 201 may include a plurality of emitters (E1, E2, E3, and E4 in FIG. 2) that emit circular beams.

The surface emitting laser package 400 according to the embodiment may provide the first electrode portion 481 and the second electrode portion 482.

The first electrode portion 481 and the second electrode portion 482 may be disposed on the substrate 410. The first electrode portion 481 and the second electrode portion 482 may be spaced apart from each other on the substrate 410.

One electrode of the first electrode portion 481 and the second electrode portion 482 may be disposed around the surface light emitting laser element 201.

The surface emitting laser device 201 may be disposed on the first electrode portion 481. In this case, the second electrode part 482 may be disposed around the surface light emitting laser element 201.

The surface emitting laser device 201 may be provided on the first electrode portion 481 by, for example, a die bonding method. The surface emitting laser device 201 may be electrically connected to the second electrode part 482. For example, the surface emitting laser device 201 and the second electrode part 482 may be electrically connected by the wire 491. The surface emitting laser device 201 may be electrically connected to the second electrode part 482 by a plurality of wires. The surface emitting laser device 201 may be electrically connected to the second electrode part 482 by a wire 491.

The number and connection positions of the wires connecting the surface emitting laser element 201 and the second electrode part 482 are determined by the size of the surface emitting laser element 201 or the degree of current diffusion required in the surface emitting laser element 201. Can be selected.

The surface emitting laser package 400 according to the embodiment may provide a first bonding portion 483 and a second bonding portion 484.

The first bonding portion 483 and the second bonding portion 484 may be disposed under the substrate 410. For example, first and second recesses spaced apart from each other are formed on a bottom surface of the substrate 410, a first bonding portion 483 is disposed in the first recess, and a second bonding portion 185 is disposed in the second recess. Can be deployed

For example, the bottom surface of the first bonding portion 483 and the bottom surface of the second bonding portion 484 may be in surface contact with a signal line (not shown) of the circuit board 460 to be electrically connected to each other. The substrate 410 may be referred to as a first substrate, and the circuit board 460 may be referred to as a second substrate.

The first bonding portion 483 and the second bonding portion 484 may be spaced apart from each other under the substrate 410. The first bonding portion 483 and the second bonding portion 484 may have circular pads, but are not limited thereto.

The first bonding portion 483 may be disposed on the bottom surface of the substrate 410. The first bonding portion 483 may be electrically connected to the first electrode portion 481. The first bonding part 483 may be electrically connected to the first electrode part 481 through the first connection line 485. For example, the first connection line 485 may be disposed in the first via hole provided in the substrate 410. The first bonding portion 483 and the first connection wiring 485 may be integrally formed using the same metal material.

The second bonding part 484 may be disposed on the bottom surface of the substrate 410. The second bonding part 484 may be electrically connected to the second electrode part 482. The second bonding part 484 may be electrically connected to the second electrode part 482 through the second connection line 486. For example, the second connection line 486 may be disposed in the second via hole provided in the substrate 410. The second bonding part 484 and the second connection wiring 486 may be integrally formed using the same metal material.

For example, the first connection line 485 and the second connection line 486 may include tungsten (W), but are not limited thereto. Tungsten (W) may be melted at a high temperature of 1000 ° C. or more, injected into the first and second via holes, and cured to form a first connection line 485 and a second connection line 486. A portion of the tungsten (W) may be cured under the substrate 410 to be formed of the first and second bonding portions 183 and 184, but is not limited thereto.

According to the embodiment, the driving power may be provided to the surface emitting laser device 201 through the circuit board 460.

In the surface light emitting laser package 400 according to the above-described embodiment, the surface light emitting laser element 201 is connected in a die bonding manner to the first electrode portion 481 and in a wire bonding manner to the second electrode portion 482. It is explained on the basis of the connection.

However, the driving power is supplied to the surface emitting laser device 201 may be variously modified. For example, the surface emitting laser device 201 may be electrically connected to the first electrode portion 481 and the second electrode portion 482 by a flip chip bonding method. In addition, the surface emitting laser device 201 may be electrically connected to both the first electrode portion 481 and the second electrode portion 482 by a wire bonding method.

The surface emitting laser package 400 according to the embodiment may provide a housing 430. The housing 430 may be disposed on the substrate 410. The housing 430 may be disposed along a peripheral area of the substrate 100. For example, the substrate 410 may include a first region (center region) and a second region (peripheral region) surrounding the first region. In this case, the surface emitting laser device 201 may be disposed on a portion of the first region of the substrate 410, and the housing 430 may be disposed on the second region of the substrate 120. The second electrode part 482 may be positioned between the first electrode part 481 and the housing 430 on the substrate 410. The housing 430 may be disposed around the surface light emitting laser element 201. The outer surface of the housing 430 may coincide with the outer surface of the substrate 410 in a vertical line.

The height of the housing 430 may be greater than the height of the surface emitting laser device 201. The housing 430 may include a material having high thermal conductivity. The housing 430 may be made of a material having a good heat dissipation property so as to efficiently discharge heat generated from the surface emitting laser device 201 to the outside. The housing 430 may include an insulating material.

For example, the housing 430 may include a ceramic material. The housing 430 may include a low temperature co-fired ceramic (LTCC) or a high temperature co-fired ceramic (HTCC) that is co-fired.

For example, the housing 430 may include a metal compound. The housing 430 may include a metal oxide having a thermal conductivity of 140 W / mK or more. For example, the housing 430 may include aluminum nitride (AlN) or alumina (Al 2 O 3).

For example, the housing 430 may include a resin-based insulating material. Specifically, the housing 430 may be made of a silicone resin, an epoxy resin, a thermosetting resin including a plastic material, or a high heat resistant material.

The housing 430 may be made of a conductive material such as metal.

For example, the housing 430 may include the same material as the substrate 410. When the housing 430 is formed of the same material as the substrate 410, the housing 430 may be integrally formed with the substrate 410.

In addition, the housing 430 may be formed of a material different from that of the substrate 410. Substrate 410 may be referred to as a housing. In this case, the substrate 410 may be referred to as a first housing, and the housing 430 may be referred to as a second housing. Alternatively, the housing 430 may be referred to as a substrate. In this case, the substrate 410 may be referred to as a first substrate, and the housing 430 may be referred to as a second substrate.

According to an embodiment, the substrate 410 and the housing 430 may be provided with a material having excellent heat radiation characteristics. Accordingly, heat generated in the surface emitting laser device 201 can be effectively released to the outside.

According to an embodiment, when the substrate 410 and the housing 430 are provided and coupled as separate components, an adhesive layer may be provided between the substrate 410 and the housing 430.

For example, the adhesive layer may include an organic material. The adhesive layer may include an epoxy-based resin. In addition, the adhesive layer may include a silicone-based resin.

On the other hand, a step may be provided in contact with the inner side in the upper region of the housing 430. For example, a recessed region 142 may be provided in an upper region of the housing 430. By way of example, the width and / or depth of the recessed area 142 may be provided in hundreds of micrometers.

The surface emitting laser package 400 according to the embodiment may provide a diffuser 440.

The diffuser 440 may be disposed on the surface emitting laser device 201. The diffuser 440 may be spaced apart from the surface emitting laser device 201. The diffusion 440 may be disposed in the recessed region 142 of the housing 430. The diffusion part 440 may be supported by the recess region 142 of the housing 430.

An adhesive layer (not shown) may be provided between the diffusion portion 440 and the recess region 142 of the housing 430. For example, the adhesive layer may be provided on the bottom surface and the side surface of the diffusion 440 in contact with the inner surface of the recess region 142. For example, the adhesive layer may include an organic material. The adhesive layer may include an epoxy-based resin. Alternatively, the adhesive layer may include a silicone resin.

The diffuser 440 may extend the angle of view of the laser beam emitted from the surface emitting laser device 201.

The diffuser 440 may include an anti-reflective function. For example, the diffusion part 440 may include an anti-reflective layer disposed on one surface of the diffusion light emitting laser device 201. The antireflective layer may be formed separately from the diffusion portion 440. The diffuser 440 may include an antireflective layer disposed on a bottom surface of the diffuser laser device 201. The antireflective layer may prevent the laser beam incident from the surface emitting laser device 201 from being reflected at the surface of the diffuser 440 and transmit the light into the diffuser 440 to improve light loss due to reflection.

The antireflective layer may be formed of, for example, an antireflective coating film and adhered to the surface of the diffuser 440. The antireflective layer may be formed on the surface of the diffusion part 440 through spin coating or spray coating. For example, the antireflective layer may be formed of a single layer or multiple layers including at least one of a group containing TiO 2, SiO 2, Al 2 O 3, Ta 2 O 3, ZrO 2, MgF 2.

The surface emitting laser package 400 according to the embodiment may provide a circuit board 460 including at least one signal line. The substrate 410 including the surface emitting laser device 201 may be mounted on the circuit board 460. For example, the circuit board 180 may include first and second signal lines. In this case, the first bonding portion 483 disposed under the substrate 100 is electrically connected to the first signal line of the circuit board 460, and is disposed under the substrate 100 so as to be connected to the first bonding portion 483. The second bonding part 484 spaced in the horizontal direction may be electrically connected to the second signal line of the circuit board 460.

According to the embodiment, since there is no step between the outer surface of the substrate 410 and the outer surface of the housing 430, the defect that occurs damage due to moisture permeation, external friction, etc. due to the step structure in the conventional surface light emitting laser package. It can be prevented.

(Mobile terminal)

14 is a perspective view of a mobile terminal to which a surface emitting laser device is applied according to an embodiment.

The vertical surface emitting laser device and the flip surface emitting laser device shown in FIG. 15 according to the first and second embodiments may be applied to the mobile terminal shown in FIG.

As shown in FIG. 14, the mobile terminal 1500 of the embodiment may include a camera module 1520, a flash module 1530, and an auto focusing device 1510 provided at a rear surface thereof. Here, the auto focus device 1510 may include one of a package of the surface emitting laser device according to the above-described embodiment as a light emitting layer.

The flash module 1530 may include a light emitting device that emits light therein. The flash module 1530 may be operated by camera operation of a mobile terminal or control of a user.

The camera module 1520 may include an image capturing function and an auto focus function. For example, the camera module 1520 may include an auto focus function using an image.

The auto focus device 1510 may include an auto focus function using a laser. The auto focus device 1510 may be mainly used in a condition in which the auto focus function using the image of the camera module 1520 is degraded, for example, a proximity or a dark environment of 10 m or less. The auto focus device 1510 may include a light emitting layer including the surface emitting laser device of the above-described embodiment, and a light receiving unit for converting light energy such as a photodiode into electrical energy.

The foregoing detailed description should not be construed as limiting in all respects, but should be considered as illustrative. The scope of the embodiments should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the embodiments are included in the scope of the embodiments.

201: surface emitting laser device
210: substrate
215: first electrode
280: pad electrode
220: first reflective layer
230: light emitting layer
240: oxide layer
241: opening
242: insulation area
250: second reflective layer
270: passivation layer
282: second electrode
285: slope
310: light guide member
400: surface emitting laser package
410: substrate
430: housing
440: diffusion
445 pattern
460: circuit board
481 and 482: electrode section
483, 484: bonding section
485, 486: connection wiring
491: wire
E: light emitting layer
E1, E2, E3: Emitter
M: mesa area
P: Pad part

Claims (18)

A first reflective layer;
An active layer on the first reflective layer;
An oxide layer on the active layer;
A second reflective layer on the oxide layer, the second reflective layer including a plurality of first regions and a second region surrounding the first region;
A plurality of light guide members in contact with the plurality of first regions of the second reflective layer; And
An electrode on the second region of the second reflective layer;
And a side surface of the light guide member having a straight surface perpendicular to the top surface of the second reflective layer. The method of claim 1,
The optical guide member has an entrance surface in contact with the second reflective surface and an exit surface extending away from an upper surface of the second reflective layer,
And the incident surface and the exit surface have the same diameter. The method of claim 1,
The ratio of the refractive index of the second reflective layer and the refractive index of the optical guide member is 1: 0.95 to 1: 1.1 surface emitting laser device. The method of claim 3,
The light guide member is a surface light emitting device comprising a transparent semiconductor material. The method of claim 4, wherein
The light guide member is a surface light emitting laser device comprising zinc oxide (ZnO). The method of claim 1,
The side surface of the light guide member is in contact with air to totally reflect the laser beam generated in the active layer to advance in the upper direction laser device. The method of claim 1,
The light guide member has a diameter larger than the diameter of the aperture (aperture) of the oxide layer. The method of claim 7, wherein
The light guide member is a surface emitting laser device having a diameter of 0.5㎛ 3㎛ larger than the diameter of the opening. The method of claim 7, wherein
The light guide member is a surface emitting laser device having a diameter of 5㎛ 15㎛. The method of claim 1,
The ratio of the diameter of the optical guide member to the height of the optical guide member is 1: 6.7 to 1: 100 surface emitting laser device. The method of claim 10,
The light guide member is a surface emitting laser device having a height of 100㎛ to 500㎛. The method of claim 1,
An end of the second electrode positioned on the second reflective layer has an inclined side surface,
A portion of the side surface of the light guide member is in contact with the inclined side surface of the second electrode. Board;
A surface emitting laser device on the substrate;
A housing surrounding the surface emitting laser element; And
And a diffusion part on the surface light emitting laser device.
The surface emitting laser device,
Including a plurality of optical guide members,
The side surface of the optical guide member has a straight surface perpendicular to the upper surface of the second reflective layer,
The light guide member is a surface light emitting laser package disposed adjacent to the diffusion portion. The method of claim 13,
The upper surface of the light guide member is in contact with the lower surface of the diffuser laser package. The method of claim 13,
The upper surface of the light guide member is a surface emitting laser package spaced apart from the lower surface of the diffusion portion by a predetermined distance. The method of claim 15,
The predetermined distance is less than 0.5 times the height of the light guide member surface emitting laser package. The method of claim 13,
The surface emitting laser device,
A first reflective layer on the substrate;
An active layer on the first reflective layer;
An oxide layer on the active layer; And
A second reflective layer on the oxide layer, the second reflective layer including a plurality of first regions and a second region surrounding the first region; And
An electrode on the second region of the second reflective layer;
And the light guide member is in contact with the plurality of first regions of the second reflective layer. A light emitting device comprising the surface emitting laser device according to any one of claims 1 to 17.

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