CN115603176A

CN115603176A - Light-emitting module

Info

Publication number: CN115603176A
Application number: CN202110721316.XA
Authority: CN
Inventors: 刘嵩; 梁栋; 张�成; 翁玮呈
Original assignee: Vertilite Co Ltd
Current assignee: Vertilite Co Ltd
Priority date: 2021-06-28
Filing date: 2021-06-28
Publication date: 2023-01-13

Abstract

The invention provides a light emitting module, comprising: the substrate at least comprises a first substrate and a second substrate, and the first substrate is positioned on the second substrate; a plurality of positive electrode pads arranged on the first substrate at intervals; the negative electrode bonding pad is arranged on the first substrate and is positioned on one side of the positive electrode bonding pad; the positive electrode connecting pads are arranged on the first substrate or the second substrate at intervals, and each positive electrode connecting pad is connected with each positive electrode pad; the negative electrode connecting pad is arranged on the same side of the positive electrode connecting pad and is connected with the negative electrode pad; and the light-emitting chip is arranged on the first substrate in an inverted mode and comprises a plurality of light-emitting units and at least one negative pole. The light-emitting module provided by the invention can independently control each light-emitting unit.

Description

Light-emitting module

Technical Field

The invention relates to the technical field of lasers, in particular to a light-emitting module.

Background

Vertical Cavity Surface Emitting Lasers (VCSELs) are developed on the basis of compound semiconductor materials, are different from other light sources such as LEDs (light Emitting diodes) and LDs (Laser diodes), have the advantages of small volume, circular output light spots, single longitudinal mode output, small threshold current, low price, easy integration into large-area arrays and the like, and are widely applied to the fields of optical communication, optical interconnection, optical storage and the like.

The vcsel array is widely used in three-dimensional sensing technology, but it is also limited, for example, the conventional vcsel is affected by the photon generation rate of the active region, and thus the power density of the vcsel array is limited. For example, the VCSEL with high power density is widely used in applications such as infrared illumination and laser radar, and in these application scenarios, the VCSEL usually generates a larger power density under a driving condition of a short pulse and a large current, and in some application conditions, different interested areas need to be respectively irradiated with laser light to improve efficiency and reduce interference, but the current structure cannot independently control each light-emitting area or unit.

Disclosure of Invention

In view of the above-mentioned drawbacks of the prior art, the present invention provides a light emitting module, which can independently control each light emitting unit and ensure that the light emitting unit has a higher power density.

To achieve the above and other objects, the present invention provides a light emitting module, including:

the substrate at least comprises a first substrate and a second substrate, wherein the first substrate is positioned on the second substrate;

a plurality of positive electrode pads arranged on the first substrate at intervals;

the negative electrode bonding pad is arranged on the first substrate and is positioned on one side of the positive electrode bonding pad;

the positive electrode connecting pads are arranged on the first substrate or the second substrate at intervals, and each positive electrode connecting pad is connected with each positive electrode pad;

the negative electrode connecting pad is arranged on the same side of the positive electrode connecting pad and is connected with the negative electrode pad;

the light-emitting chip is arranged on the first substrate in an inverted mode and comprises a plurality of light-emitting units and at least one negative pole;

the driving chip is arranged on the first substrate or the second substrate, an anode pin of the driving chip is connected with the anode connecting pad, and a cathode pin of the driving chip is connected with the cathode connecting pad;

each light-emitting unit is arranged on the positive electrode bonding pad, and the negative electrode column is arranged on the negative electrode bonding pad;

the light emitting unit comprises at least two active layers, and a tunnel junction is arranged between the at least two active layers.

Further, when the positive electrode connection pad is disposed on the second substrate, the driving chip is disposed on the second substrate.

Furthermore, a plurality of first metal columns are arranged in the first substrate, the first metal columns penetrate through the first substrate, and the positive bonding pad and the negative bonding pad are respectively located on the first metal columns.

Furthermore, a plurality of first metal layers are arranged on the surface, contacting the first substrate, of the second substrate, the plurality of first metal layers are insulated from one another, and the first metal layers are connected with the positive electrode bonding pad through the first metal columns.

Furthermore, a plurality of second metal columns are arranged in the second substrate, the second metal columns penetrate through the second substrate, part of the second metal columns are used for connecting the first metal layer and the anode connecting pad, and part of the second metal columns are connected with the first metal columns and the cathode connecting pad.

Further, when the positive electrode connecting pad is arranged on the first surface, the driving chip is arranged on the first substrate, the driving chip is fixed on the first substrate through the negative electrode connecting pad, and the positive electrode connecting pad is located on the first metal column.

Furthermore, the substrate further comprises a third substrate, the second substrate is located on the third substrate, a second metal layer is arranged on a contact surface of the second substrate and the third substrate, and the second metal layer is further connected with the second metal column.

Further, the negative electrode connection pad is connected to the second metal layer through a third metal column, and the third metal column penetrates through the first substrate and the second substrate.

Further, the oxide aperture of the light emitting unit is 10-50 micrometers.

Further, the height of the negative pole is flush with the height of the light emitting unit.

In summary, the present invention provides a light emitting module, in which the substrate may include a first substrate and a second substrate, and the substrate may be an insulating substrate. The first substrate is provided with a positive electrode bonding pad and a negative electrode bonding pad, and the positive electrode bonding pad and the negative electrode bonding pad are respectively connected with a light-emitting unit and a negative electrode post of the light-emitting chip. The second substrate is provided with a positive electrode connecting pad and a negative electrode connecting pad, the contact surfaces of the first substrate and the second substrate are provided with a first metal layer, and the first substrate and the second substrate are respectively provided with a metal column, so that each positive electrode connecting pad is connected with each positive electrode pad, and each negative electrode connecting pad can be connected with each negative electrode pad. Therefore, when each positive electrode pin of the driving chip is connected with each positive electrode connecting pad, the negative electrode pin of the driving unit is connected with the negative electrode connecting pad, and therefore, each light-emitting unit is independently controlled. And the light-emitting unit comprises at least two active layers which are connected in series through a tunnel junction, so that the power density of the light-emitting unit can be improved.

In summary, in the present invention, the substrate may further include a third substrate, and the second substrate is located on the third substrate, so that the negative electrode connection pad may be disposed on the first substrate, and the driving chip is disposed on the negative electrode connection pad, and meanwhile, the positive electrode connection pad is disposed on the first substrate, so that the driving chip and the light emitting chip are located on the same surface of the substrate. The cathode connection pad and the cathode connection pad are then connected by the metal posts, thereby enabling the driving chip to individually control each light emitting cell.

In summary, the driving chip and the light emitting chip are directly disposed on the substrate, so that the length of the metal wire can be reduced, the influence of the inductor on the light emitting chip can be reduced, and the performance of the light emitting module can be improved. Of course, the present invention may also dispose the light emitting chip on the substrate, and then connect the substrate and the driving chip through the circuit board.

Drawings

FIG. 1: the structure of the light-emitting chip is shown schematically.

FIG. 2 is a schematic diagram: schematic illustration of the epitaxial structure in the present invention.

FIG. 3: another schematic diagram of a light emitting chip in the present invention.

FIG. 4 is a schematic view of: the substrate of the present invention is schematically illustrated.

FIG. 5: the first substrate of fig. 4 is a plan view of the present invention.

FIG. 6: the second substrate of fig. 4 is a plan view of the present invention.

FIG. 7 is a schematic view of: the second substrate of fig. 4 is a bottom view of the present invention.

FIG. 8: another structure diagram of the substrate of the invention.

FIG. 9: the top view of the first substrate of fig. 8 in the present invention.

FIG. 10: the second substrate of fig. 8 is a plan view of the present invention.

FIG. 11: the third substrate of fig. 8 according to the present invention is a plan view.

FIG. 12: the invention discloses a schematic diagram of a light-emitting module.

FIG. 13 is a schematic view of: another schematic diagram of the light emitting module of the present invention.

Detailed Description

The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention.

It should be noted that the drawings provided in the present embodiment are only for illustrating the basic idea of the present invention, and the components related to the present invention are only shown in the drawings rather than drawn according to the number, shape and size of the components in actual implementation, and the type, quantity and proportion of the components in actual implementation may be changed freely, and the layout of the components may be more complicated.

As shown in fig. 1, the present embodiment provides a light emitting chip 200, and the light emitting chip 200 may be a vertical cavity surface emitting laser, such as a back surface emitting laser. The light emitting chip 200 may include at least one negative electrode tab 201 and at least one light emitting unit 202. Of course, the light emitting chip 200 may further include a plurality of light emitting arrays, each of which includes at least one light emitting unit 202 therein. The light emitting unit 202 is used for emitting laser beams, the negative pole 201 can also play a supporting role, and the height of the negative pole 201 is the same as that of the positive pole on the light emitting unit 202.

As shown in fig. 1, the light emitting chip 200 may include a substrate 210, and the substrate 210 may be any material suitable for forming a vertical cavity surface emitting laser, such as a substrate of gallium arsenide (GaAs) or other semiconductor material. The substrate 210 may be an N-type doped semiconductor substrate, a P-type doped semiconductor substrate, or a semi-insulating substrate, and the doping may reduce the contact resistance of the ohmic contact between the subsequently formed ohmic metal electrode and the semiconductor substrate, in this embodiment, the substrate 210 is, for example, an N-type doped semiconductor substrate (conductive substrate).

As shown in fig. 1-2, three epitaxial structures 220 are formed on the substrate 210, the three epitaxial structures 220 have the same structure, and the three epitaxial structures 220 can be used to form the negative electrode pillar 201 and the light emitting unit 202.

As shown in fig. 2, fig. 2 is a schematic structural diagram of the epitaxial structure 220. The epitaxial structure 220 may include a first reflective layer 221, at least two active layers 222, a tunnel junction 223 and a second reflective layer 224 from bottom to top. The first reflective layer 221 may be formed of, for example, a stack of two materials having different refractive indices, including AlGaAs and GaAs, or AlGaAs of a high aluminum composition and AlGaAs of a low aluminum composition, the first reflective layer 221 may be an N-type mirror, and the first reflective layer 221 may be an N-type bragg mirror. The second reflective layer 224 may include a stack of two materials having different refractive indexes, i.e., alGaAs and GaAs, or AlGaAs having a high aluminum composition and AlGaAs having a low aluminum composition, the second reflective layer 224 may be a P-type mirror, and the second reflective layer 224 may be a P-type bragg mirror.

As shown in fig. 2, in the present embodiment, two active layers 222 are formed on the first reflective layer 221, and a tunnel junction 223 is formed in the two active layers 222, that is, the two active layers 222 are separated by the two tunnel junctions 223, that is, the active layers 222 are connected in series by the tunnel junction 223. The active layer 222 includes a first semiconductor layer 2221, an active region 2222, and a second semiconductor layer 2223, and the active region 2222 is located between the first semiconductor layer 2221 and the second semiconductor layer 2223. In fig. 10, the first semiconductor layer 2221 and the second semiconductor layer 2223 include one single material layer, but each of the first semiconductor layer 2221 and the second semiconductor layer 2223 may include more than one layer. The first semiconductor layer 2221 and the second semiconductor layer 2223 may comprise GaAs, where the first semiconductor layer 2221 may be lightly N-type doped and the second semiconductor layer 2223 may be P-type doped. In some embodiments, the first semiconductor layer 2221 and the second semiconductor layer 2223 may also include other materials, which may be specifically configured with different dopings. In this embodiment, the active region 2222 may also be referred to as an active region, and the active region 2222 includes a plurality of quantum structure layers therein, the quantum structure layers having a bandgap wavelength, and each of the quantum structure layers emitting light at an operating wavelength.

As shown in fig. 2, in some embodiments, three, four or more active layers 222 may be further formed between the first and second

reflective layers

221 and 224, and the active layers 222 are connected in series by tunnel junctions 223,

as shown in fig. 2, in the present embodiment, a tunnel junction 223 is further formed between the two active layers 222, the tunnel junction 223 may be, for example, a GaAs homogeneous tunnel junction, the absorption loss of photons may be reduced by using the ultra-thin layer of the tunnel junction 223, and the tunnel junction 223 may be placed at a standing wave node of an optical resonant cavity of the vcsel, so that the interaction between the tunnel junction 223 and an optical field may be reduced, and the effect of reducing the loss is also achieved. In the embodiment, the tunnel junctions 223 are located between the active layers 222, so that the plurality of active layers 222 form a series structure, and carriers can be recycled, thereby increasing the light intensity of each light emitting unit 202 without increasing the current, and thus increasing the power density of the light emitting unit 202.

As shown in fig. 1, a first electrode 211 is further formed on the epitaxial structure 220, and the first electrode 211 is located on the top of the epitaxial structure 220. An insulating layer 213 is also provided on the first electrode 211. The insulating layer 213 completely covers the epitaxial structure 220 forming the negative pillar 201, that is, the insulating layer 213 extends from the top of the epitaxial structure 220 along the sidewalls of the epitaxial structure 220 onto the substrate 210. The insulating layer 213 does not completely cover the epitaxial structure 220 forming the light emitting unit 202, i.e., the insulating layer 213 forms an opening on the top of the epitaxial structure 220, and thus does not completely cover the top of the epitaxial structure 220, i.e., may expose a portion of the first electrode 211. An insulating layer 213 is also formed between the two light emitting cells 202, and thus the two light emitting cells 202 can be prevented from contacting each other.

As shown in fig. 1, a plating metal layer 214 is further disposed on each epitaxial structure 220, and a solder layer may be further included on the plating metal layer 214, where the plating metal layer 214 is, for example, titanium gold. The solder layer is, for example, silver-tin alloy. Since the insulating layer 213 completely covers the epitaxial structure 220 forming the negative electrode post 201, the plating metal layer 214 cannot be connected to the first electrode 211. Since the insulating layer 213 does not completely cover the epitaxial structure 220 forming the light emitting unit 202, the plated metal layer 214 may be connected to the first electrode 211, and thus current may enter the epitaxial structure 220 through the first electrode 211, thereby emitting a laser beam. Since the insulating layer 213 is provided between the metal layers 214, when a current is applied to the middle light emitting cell 202, the current cannot flow into the right light emitting cell 202.

As shown in fig. 1, a second electrode 212 is further disposed between the left-side epitaxial structure 220 and the middle epitaxial structure 220, the second electrode 212 is located on the substrate 210, an insulating layer 213 is disposed between the second electrode 212 and the left-side epitaxial structure 220, an insulating layer 213 is disposed between the second electrode 212 and the middle epitaxial structure 220, and the second electrode 212 is further connected to the plating metal layer 214. In the present embodiment, the two light emitting units 202 are disposed in a manner of sharing a cathode and an anode, and the metal layer 214 between the two light emitting units 202 is disconnected, so that independent control between the two light emitting units 202 can be realized. Meanwhile, since only the negative electrode is included on the negative electrode pillar 201, and the positive electrode is not included, the epitaxial structure in the negative electrode pillar 201 cannot emit a laser beam.

As shown in fig. 1-2, a current confinement layer 215 is further formed in each epitaxial structure 220, and the current confinement layer 215 may be located in the first reflective layer 221 or, of course, in the second reflective layer 224. The current confinement layer 215 can form a light emitting hole in the epitaxial structure 220, the diameter of the light emitting hole is in the range of 10-50 microns, that is, the range of the oxide aperture is in the range of 10-50 microns, wherein preferably, the diameter of the light emitting hole can be larger than 20 microns, that is, the oxide aperture is larger than 20 microns, which is beneficial to generating larger power, and simultaneously, as the effective light emitting area is increased, the filling rate is increased, and the same power can be generated, so that the chip area can be saved. The current confinement layer 215 includes one of an air pillar type current confinement structure, an ion implantation type current confinement structure, a buried heterojunction type current confinement structure, and an oxidation confinement type current confinement structure, and the oxidation confinement type current confinement structure is used in this embodiment.

As shown in fig. 3, the present embodiment further provides another light emitting chip 200, and the difference between fig. 3 and fig. 9 is that the substrate 210 in fig. 3 is a semi-insulating substrate, and the substrate 210 may be a sapphire substrate or other material substrate, or at least the top surface of the substrate 210 is composed of one of silicon, gallium arsenide, silicon carbide, aluminum nitride, and gallium nitride. An N-type conductive layer 211 is further formed on the substrate 210, and the epitaxial structures 220 are all located on the N-type conductive layer 211, so as to realize the circulation of current.

As shown in fig. 4, the present embodiment provides a substrate 100, and the substrate 100 may include a first substrate 110 and a second substrate 120. The first substrate 110 is positioned on the second substrate 120. The thickness of the first substrate 110 may be equal to the thickness of the second substrate 120. Of course, the first substrate 110 and the second substrate 120 may also be a two-layer structure in the same substrate. Of course, the substrate 100 may further include a third substrate or a fourth substrate. The substrate 100 may be an insulating substrate, such as AlN, beO, or the like. Therefore, the first substrate 110 and the second substrate 120 can be insulating substrates, and when metal wires or metal pillars are disposed on the first substrate 110 or the second substrate 120, the first substrate 110 and the second substrate 120 can perform an insulating function, thereby preventing a short circuit phenomenon.

As shown in fig. 4-5, fig. 5 is a top view of the first substrate 110. The cross-sectional view of the substrate 100 in fig. 4 can be obtained from the cross-sectional view along the directionbase:Sub>A-base:Sub>A in fig. 5. A plurality of positive electrode pads 111 and a plurality of negative electrode pads 112 are provided on the surface of the first substrate 110 remote from the second substrate 120, and in order to distinguish the positive electrode pads 111 from the negative electrode pads 112, the negative electrode pads 112 are indicated by dotted lines, and the positive electrode pads 111 are indicated by solid lines. In the present embodiment, the negative electrode pads 112 are located on one side of the positive electrode pads 111, the positive electrode pads 111 and the negative electrode pads 112 are disposed at intervals, and the positive electrode pads 111 and the negative electrode pads 112 are arranged in a matrix, for example. In the present embodiment, one negative electrode pad 112 and two positive electrode pads 111 are defined asbase:Sub>A pad group in thebase:Sub>A-base:Sub>A direction, so that three pad groups, each of which can be connected tobase:Sub>A light emitting array, can be shown in fig. 2. When an arbitrary pad group is driven, an arbitrary light emitting array can be driven accordingly. The positive electrode pad 111 is used for connecting the light-emitting units in the light-emitting array, and the negative electrode pad 112 is used for connecting the negative poles in the light-emitting array; therefore, current can be supplied to the light emitting cell through the positive electrode pad 111 and the negative electrode pad 112, thereby activating the light emitting cell. The positive electrode pad 111 and the negative electrode pad 112 may be made of a conductive material, such as Ti, ni, au, sn, or the like. The areas of the positive electrode pad 111 and the negative electrode pad 112 may be the same.

As shown in fig. 4 to 5, a plurality of first metal posts 113 are disposed on the first substrate 110, and the first metal posts 113 penetrate the first substrate 110. The first metal columns 113 are respectively located below the positive electrode bonding pads 111 and the negative electrode bonding pads 112, that is, one first metal column 113 is connected to each positive electrode bonding pad 111 and each negative electrode bonding pad 112, and since the first substrate 110 is an insulating substrate, a short circuit phenomenon does not occur between the plurality of first metal columns 113. The first metal pillar 113 may be formed by forming a first via hole in the first substrate 110 by a sintering process (including, but not limited to, design-specific modification), and then depositing a metal layer into the first via hole. As can be seen from fig. 5, in order to show the first metal pillar 113, the first metal pillar 113 is indicated by a solid line. The area of the first metal pillar 113 may be smaller than the area of the positive electrode pad 111, that is, when a light emitting chip is directly mounted (die bonding) through the positive electrode pad 111, a wire bonding process between the light emitting chip and the pad is omitted, so that the resistance may be reduced, and the inductance may be reduced. In this embodiment, the area of the positive electrode pad 111 refers to the area of the top view of the positive electrode pad 111 in fig. 5, and the area of the first metal pillar 113 refers to the area of the top view of the first metal pillar 113 in fig. 5.

As shown in fig. 4 and 6, fig. 6 is a top view of the second substrate 120. A plurality of second metal pillars 121 are disposed on the second substrate 120, and a portion of the plurality of second metal pillars 121 may be directly connected to the first metal pillars 113, that is, the second metal pillars 121 are located below the first metal pillars 113. For example, the three second metal posts 121 on the left side in fig. 6 connect the three first metal posts 113 on the left side in fig. 4. A portion of the plurality of second metal pillars 121 may be located on one side of the second substrate 120, that is, on one side of the first metal pillars 113, for example, the 6 second metal pillars 121 on the right side in fig. 6 are respectively connected to each first metal pillar 113 through the first metal layer 122. The first metal layers 122 are disposed at intervals, and since the second substrate 120 is an insulating substrate, a short circuit phenomenon does not occur between the first metal layers 122. The material of the first metal layer 122 may be Cu or Au. In this embodiment, the second metal pillar 121 penetrates the second substrate 120, and the second metal pillar 121 is directly or indirectly connected to the first metal pillar 113, so that the positive pad 111 and the negative pad 112 on the first substrate 110 can extend downward through the first metal pillar 113, the second metal pillar 121 and the first metal layer 122, and are connected to the positive connection pad 123 and the negative connection pad 124, respectively. The first metal layer 122 is located on the second substrate 120, but may be disposed on the contact surface of the first substrate 110 and the second substrate 120. Note that, in order to show the connection relationship between the first metal pillar 113 and the second metal pillar 121, the first metal pillar 113 is shown in fig. 6.

As shown in fig. 4-7, fig. 7 is shown as a bottom view of second substrate 120. A plurality of positive electrode connection pads 123 and one negative electrode connection pad 124 are disposed on the second substrate 120. The positive connection pad 123 is located on the right side of the second substrate 120, and the negative connection pad 124 is located on the left side of the second substrate 120, for example, six positive connection pads 123 are disposed on the second substrate 120, the positive connection pads 123 are spaced apart from each other, and the second substrate 120 is an insulating substrate, so that a short circuit phenomenon does not occur. In the present embodiment, each positive connection pad 123 connects each second metal pillar 121, and the negative connection pad 124 connects a plurality of second metal pillars 121, that is, the plurality of second metal pillars 121 share one negative connection pad 124. In the present embodiment, the positive connection pad 123 is connected to the positive pad 111 through the second metal pillar 121, the first metal layer 122, the first metal pillar 113, and the negative connection pad 124 is connected to the negative pad 112 through the second metal pillar 121, and the first metal pillar 113, that is, each positive connection pad 123 is connected to each positive pad 111. The negative connection pad 124 is connected to the plurality of negative pads 112.

As shown in fig. 4 to 7, in the present embodiment, by designing the first substrate 110 and the second substrate 120, and both the first substrate 110 and the second substrate 120 are made of insulating materials, when the first metal pillar 113, the positive electrode pad 111, or the negative electrode pad 112, or other metal materials are disposed in the first substrate 110 and the second substrate 120, it can be ensured that no short circuit occurs between the metal materials.

As shown in fig. 8, the present embodiment also provides another substrate 100, and the substrate 100 may include a first substrate 110, a second substrate 120, and a third substrate 130. The second substrate 120 is positioned on the third substrate 130, and the first substrate 110 is positioned on the second substrate 120. The first substrate 110 to the third substrate 130 may be insulating ceramic substrates.

As shown in fig. 8-9, fig. 9 isbase:Sub>A top view of fig. 8, and fig. 8 isbase:Sub>A cross-sectional view of fig. 9 in the directionbase:Sub>A-base:Sub>A. A plurality of positive electrode pads 111 and a plurality of negative electrode pads 112 are provided on the first substrate 110. The positive electrode pads 111 and the negative electrode pads 112 may be arranged at intervals, for example, in a matrix manner. A plurality of first metal pillars 113 are further disposed in the first substrate 110, and the first metal pillars 113 penetrate through the first substrate 110. A negative electrode connection pad 124 is further provided on the first substrate 110, and the negative electrode connection pad 124 is used for connecting a driving chip. A plurality of positive connection pads 123 are further disposed on the first substrate 110, and the positive connection pads 123 are disposed at intervals, that is, the positive pads 111, the negative pads 112, the negative connection pads 124 and the positive connection pads 123 are located on the same surface of the first substrate 110. The first metal pillar 113 is also located under the positive electrode pad 111, the negative electrode pad 112, and the positive electrode connection pad 123, and the first metal pillar 113 is connected to these pads, respectively. Since the first substrate 110 is made of an insulating material, a short circuit phenomenon does not occur between the pads.

As shown in fig. 8 and 10, fig. 10 is a top view of the second substrate 120. A plurality of second metal pillars 121 are disposed on the second substrate 120, the second metal pillars 121 penetrate through the second substrate 120, and the second metal pillars 121 are located below the first metal pillars 113, that is, the first metal pillars 113 and the second metal pillars 121 are directly connected. For example, the second metal pillar 121 on the left side in fig. 10 is directly connected to the first metal pillar 113 on the left side in fig. 8, that is, the second metal pillar 121 is connected to the first metal pillar 113 under the negative electrode pad 112. A plurality of first metal layers 122 are further disposed on the second substrate 120, the first metal layers 122 are spaced from each other, and the first metal layers 122 enable the positive electrode bonding pad 111 to be connected to the positive electrode connection bonding pad 123, so that the positive electrode bonding pad 111 and the positive electrode connection bonding pad 123 are in a one-to-one correspondence relationship. Of course, in some embodiments, the first metal layers 122 may also be located on the contact surfaces of the first substrate 110 and the second substrate 120.

As shown in fig. 8 and 11, fig. 11 is a top view of the third substrate 130. The second metal layer 131 is located on the contact surface of the third substrate 130 and the second substrate 120, and the second metal layer 131 is used for connecting the second metal pillar 121 and the third metal pillar 132. Since the second metal pillar 121 is connected to the first metal pillar 113, the first metal pillar 113 is connected to the negative electrode pad 112. The third metal pillar 132 penetrates through the first substrate 110 and the second substrate 120, and the third metal pillar 132 is located below the negative connection pad 124, so that the second metal layer 131 can be connected to the driving chip through the third metal pillar 132, and therefore, the connection between the negative pin of the driving chip and the second metal layer 131 can be achieved. It should be noted that, a plurality of cathode pads 112 are connected through a second metal layer 131, and the area of the second metal layer 131 is larger, so that the contact resistance can be reduced, and the performance of the light emitting module can be improved. Meanwhile, since the cathode pads 112 are arranged at intervals, the process of forming the second metal layer 131 is simpler by connecting a plurality of cathode pads 112 through one second metal layer 131.

As shown in fig. 8, when the light emitting chips are disposed on the positive electrode pad 111 and the negative electrode pad 112, and the driving chip is disposed on the negative electrode connection pad 124, each positive electrode pin in the driving chip is then connected to each positive electrode connection pad 123, and the negative electrode pin in the driving chip 300 is connected to the third metal pillar 132, so that each light emitting cell can be driven by the driving chip, thereby independently controlling each light emitting cell. Since the driving chip is directly fixed on the substrate 100, a gold wire between the light emitting chips can be omitted, inductance generated by a metal wire is reduced, and performance of the light emitting module is improved.

As shown in fig. 5, in the present embodiment, the first metal layer 122 is located on the second substrate 120, and of course, a portion of the first metal layer 122 may also be disposed on the second substrate 120, and a portion of the first metal layer 122 is disposed on the third substrate 130, so that when the light emitting module 10 operates, the heat dissipation of the first metal layer 122 is facilitated.

In some embodiments, the substrate 100 may also include more sub-substrates, such as four or more sub-substrates. And these sub-substrates may be insulating substrates.

As shown in fig. 12, the present embodiment further provides a light emitting module 10, and the light emitting module 10 may include a substrate 100, a light emitting chip 200 and a driving chip 300. The light emitting chip 200 and the driving chip 300 are disposed at opposite sides of the substrate 100. The structure of the light emitting chip 200 may refer to fig. 1, and the structure of the substrate 100 may refer to fig. 5. Both the light emitting chip 200 and the driving chip 300 may be directly disposed on the substrate 100. Of course, the light emitting chip 200 may be disposed on the substrate 100, and then the substrate 100 and the driving chip 300 are connected through a circuit board. In this embodiment, the light emitting chip 200 may be a light emitting diode chip, a vertical cavity surface emitting laser.

As shown in fig. 12, in the present embodiment, the light emitting chip 200 is disposed on the first substrate 110, that is, the negative electrode pillar 201 in the light emitting chip 200 is connected to the negative electrode pad 112, and the light emitting unit 202 is connected to the positive electrode pad 111. The driving chip is disposed on the second substrate 120, that is, the positive electrode pin 301 of the driving chip 300 is connected to the positive electrode connection pad 123, and the negative electrode pin 302 is connected to the negative electrode connection pad 124. When the driving chip 300 drives the middle light emitting unit 202, the current enters the middle light emitting unit 202 from the positive pin 301, the second metal pillar 121, the first metal layer 122, the first metal pillar 113 and the positive pad 111, and the current cannot enter the right light emitting unit 202 because the positive pin 301 and the positive pad 111 are in a one-to-one relationship. After the current flows into the middle light emitting unit 202, it enters the negative electrode pad 112 through the substrate 210 and the negative electrode post 201, and then enters the driving chip 300 through the first metal post 113, the second metal post 121, the negative electrode connection pad 124 and the negative electrode pin 302, so that the middle light emitting unit 202 emits a laser beam. When a current enters the negative electrode post 201, the negative electrode post 201 cannot emit a laser beam because the epitaxial structure inside the negative electrode post 201 includes only a negative electrode and does not include a positive electrode. By configuring the positive electrode pin 301 of the driving chip 300 and the light emitting units 202 in the light emitting chip 200 to have a one-to-one correspondence relationship, the driving chip 300 can independently control each light emitting unit 202. Meanwhile, the issue unit 202 has a plurality of active layers connected in series through tunnel junctions, so that the power density of the light emitting unit 202 can be increased, and the performance of the light emitting module 10 can be improved.

As shown in fig. 13, the present embodiment further provides a light emitting module 10, where the light emitting module 10 includes a substrate 100, a light emitting chip 200 and a driving chip 300. The light emitting chip 200 and the driving chip 300 are both disposed on the first substrate 110, that is, the light emitting chip 200 and the driving chip 300 are disposed on the same side.

As shown in fig. 8 and 13, the structure of the substrate 100 may refer to fig. 8, and the structure of the light emitting chip 200 may refer to fig. 1. The light emitting unit 202 in the light emitting chip 200 is connected to the positive electrode pad 111, and the negative electrode post 201 in the light emitting chip 200 is connected to the negative electrode pad 112. The positive terminal 301 of the driving chip 300 is connected to the positive connection pad 123, and the negative terminal 302 of the driving chip 300 is connected to the negative connection pad 124. Since the positive electrode connection pad 123 is connected to the positive electrode pad 111 and the negative electrode connection pad 124 is connected to the negative electrode pad 112, it is possible to realize that the driving chip 300 drives the light emitting chip 200. The process of the driving chip 300 independently controlling each light emitting unit 202 may refer to the above description.

In summary, the present invention provides a light emitting module, in which the substrate may include a first substrate and a second substrate, and the substrate may be an insulating substrate. The first substrate is provided with a positive electrode bonding pad and a negative electrode bonding pad, and the positive electrode bonding pad and the negative electrode bonding pad are respectively connected with a light-emitting unit and a negative electrode post of the light-emitting chip. The second substrate is provided with a positive electrode connecting pad and a negative electrode connecting pad, the contact surfaces of the first substrate and the second substrate are provided with a first metal layer, and the first substrate and the second substrate are respectively provided with metal columns, so that each positive electrode connecting pad is connected with each positive electrode pad, and each negative electrode connecting pad can be connected with each negative electrode pad. Therefore, when each positive electrode pin of the driving chip is connected with each positive electrode connecting pad, the negative electrode pin of the driving unit is connected with the negative electrode connecting pad, and therefore, each light-emitting unit is independently controlled. And the light-emitting unit comprises at least two active layers which are connected in series through a tunnel junction, so that the power density of the light-emitting unit can be improved.

In summary, in the present invention, the substrate may further include a third substrate, and the second substrate is located on the third substrate, so that the negative connection pad may be disposed on the first substrate, and the driving chip is disposed on the negative connection pad, and the positive connection pad is disposed on the first substrate, so that the driving chip and the light emitting chip are located on the same surface of the substrate. The cathode connection pad and the cathode connection pad are then connected by the metal posts, thereby enabling the driving chip to individually control each light emitting cell.

In summary, the driving chip and the light emitting chip are directly disposed on the substrate, so that the length of the metal wire can be reduced, the influence of the inductor on the light emitting chip can be reduced, and the performance of the light emitting module can be improved. Of course, the invention can also arrange the light emitting chip on the substrate, and then connect the substrate and the driving chip through the circuit board.

The above description is only a preferred embodiment of the present application and a description of the applied technical principle, and it should be understood by those skilled in the art that the scope of the present invention related to the present application is not limited to the technical solution of the specific combination of the above technical features, and also covers other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept, for example, the technical solutions formed by mutually replacing the above features with (but not limited to) technical features having similar functions disclosed in the present application.

Other technical features than those described in the specification are known to those skilled in the art, and are not described herein in detail in order to highlight the innovative features of the present invention.

Claims

1. A light emitting module, comprising:

2. The light emitting module of claim 1, wherein the driving chip is disposed on the second substrate when the positive connection pad is disposed on the second substrate.

3. The illumination module as recited in claim 1 wherein a plurality of first metal posts are disposed within the first substrate, the first metal posts extend through the first substrate, and the positive bonding pad and the negative bonding pad are respectively disposed on the first metal posts.

4. The light emitting module of claim 3, wherein a plurality of first metal layers are disposed on a surface of the second substrate contacting the first substrate, the plurality of first metal layers are insulated from each other, and the first metal layers are connected to the positive electrode pad through the first metal posts.

5. The lighting module of claim 4, wherein a plurality of second metal posts are disposed in the second substrate, the second metal posts extend through the second substrate, a portion of the second metal posts are used for connecting the first metal layer and the positive connection pad, and a portion of the second metal posts are used for connecting the first metal posts and the negative connection pad.

6. The illumination module as recited in claim 4 wherein when the positive connection pad is disposed on the first surface, the driver chip is disposed on the first substrate, the driver chip is fixed on the first substrate by the negative connection pad, and the positive connection pad is disposed on the first metal post.

7. The illumination module as recited in claim 4, wherein the substrate further comprises a third substrate, the second substrate is disposed on the third substrate, a second metal layer is disposed on a contact surface of the second substrate and the third substrate, and the second metal layer is further connected to the second metal pillar.

8. The lighting module of claim 7, wherein the negative connection pad is connected to the second metal layer by a third metal pillar, the third metal pillar penetrating the first substrate and the second substrate.

9. The lighting module of claim 1, wherein the oxide aperture of the light emitting unit is 10-50 μm.

10. The light emitting module of claim 1, wherein the height of the negative pole is flush with the height of the light emitting unit.