CN111934193B

CN111934193B - LD chip inorganic packaging structure and preparation method thereof

Info

Publication number: CN111934193B
Application number: CN202011093259.7A
Authority: CN
Inventors: 席庆男; 邓群雄; 覃志伟; 李志�
Original assignee: Shandong Novoshine Optoelectronics Co ltd
Current assignee: Yuanxu Semiconductor Technology (Beijing) Co.,Ltd.
Priority date: 2020-10-14
Filing date: 2020-10-14
Publication date: 2021-01-05
Anticipated expiration: 2040-10-14
Also published as: CN111934193A

Abstract

The invention belongs to the technical field of semiconductors, and provides an LD chip inorganic packaging structure and a preparation method thereof, wherein the LD chip inorganic packaging structure comprises a ceramic substrate, two surfaces of the ceramic substrate are plated with first metal layers, the first metal layers of electrode areas on the two surfaces of the ceramic substrate are connected, an LD chip is arranged on the first metal layer of a heat dissipation area on one surface, and the anode and the cathode of the LD chip are respectively connected with the first metal layers of the electrode areas on the same surface; the light-emitting side of the LD chip is sequentially provided with an optical fiber and a reflector, a light source of the LD chip penetrates through the center of the optical fiber, and one side of the reflector, which is close to the optical fiber, is an inclined reflecting surface; one side of the ceramic substrate is also provided with an outer frame, the top of the outer frame is matched and covered with a fluorescent cover plate, and the fluorescent cover plate is of a diaphragm structure. The invention realizes the inorganic packaging in the true sense, the LD chip can not contact the water vapor and the organic components, the service life is greatly prolonged, and the packaging structure has smaller volume, greatly improved heat dissipation effect and simpler and more convenient installation and use.

Description

LD chip inorganic packaging structure and preparation method thereof

Technical Field

The invention relates to the technical field of semiconductors, in particular to an LD chip inorganic packaging structure and a preparation method thereof.

Background

An LD (semiconductor laser) is a laser using a semiconductor material as a working substance, has many advantages such as simple fabrication, low cost, high efficiency, long life, good beam quality, and light weight, has been rapidly developed in recent years, and has become a research focus of much interest in the laser field in the world today. In three aspects of manufacturing of LD chips, die (module) packaging and product application, packaging process and equipment are closer to the market, and the promotion effect on the industry is more direct. The LD chip package technology is a package of a light emitting chip, and has a great difference compared with an integrated circuit package, the function of the package is to provide sufficient protection for the chip, prevent the chip from being exposed in the air for a long time or being damaged mechanically to fail, to improve the stability of the chip, and also need to have good light extraction efficiency and good heat dissipation, and the good package can make the chip have better light emitting efficiency and heat dissipation environment, thereby improving the service life.

At present, the encapsulation of laser chip is mostly the TO encapsulation, and conventional module is the chip of TO encapsulation and uses in addition lens, becomes the light parallel light with the light. Because of the structure of the TO package, the LD chip is easy TO contact with water vapor and organic components, thereby greatly reducing the service life of the LD chip, meanwhile, the TO package has large volume, cannot be used in a small module, is installed in an insertion way, is inconvenient TO install, has high power of the LD chip, generates large heat, has poor heat dissipation effect of the TO package, further influences the performance and the service life of the chip, in addition, the ceramic package adopting ceramic as a heat sink at present, although the heat dissipation effect of a ceramic substrate is good, welding materials used for bonding the chip are limited, adhesives such as silver glue and the like are generally needed for bonding the chip TO the ceramic heat sink, but the heat conductivity of a cured layer formed by the adhesives is poor, can obstruct the heat conduction between the chip and the ceramic heat sink, the heat dissipation effect is TO be further improved, in addition, the bonding strength of the cured layer formed by the adhesives is easy TO, separation between the chip and the ceramic heat sink may even occur. Therefore, the development of an inorganic packaging structure of an LD chip and a preparation method thereof not only has urgent research value, but also has good economic benefit and industrial application potential, which is the basis and the impetus for the invention to be completed.

Disclosure of Invention

The present inventors have conducted intensive studies to overcome the above-identified drawbacks of the prior art, and as a result, have completed the present invention after having made a great deal of creative efforts.

Specifically, the technical problems to be solved by the present invention are: the inorganic packaging structure of the LD chip and the preparation method thereof are provided to solve the technical problems that the LD chip of the existing laser chip packaging device is easy to contact with water vapor and organic components, the service life is shortened, and the size is large and the heat dissipation effect is poor.

In order to solve the technical problems, the technical scheme of the invention is as follows:

an inorganic packaging structure of an LD chip comprises a ceramic substrate, wherein two sides of the ceramic substrate are plated with first metal layers, each first metal layer comprises a heat dissipation area and an electrode area, the first metal layers of the electrode areas on the two sides of the ceramic substrate are connected, the first metal layer of one heat dissipation area is provided with the LD chip, and the positive electrode and the negative electrode of the LD chip are respectively connected with the first metal layer of the electrode area on the same side;

the light-emitting side of the LD chip is sequentially provided with an optical fiber and a reflector, the optical fiber is arranged corresponding to the light-emitting point of the LD chip, and one side of the reflector close to the optical fiber is an inclined reflecting surface;

one side of the ceramic substrate is also provided with an outer frame, a fluorescent cover plate is covered on the top of the outer frame in a matching manner, the fluorescent cover plate is of a diaphragm structure, and the ceramic substrate, the outer frame and the fluorescent cover plate form a packaging area for accommodating an internal light path device.

As an improved technical scheme, through holes are formed in two end portions of the ceramic substrate, and the first metal layers in the electrode areas on the two sides of the ceramic substrate are connected through the through holes respectively.

As an improved technical solution, the first metal layer on one side of the ceramic substrate further includes a peripheral region, the peripheral region surrounds the heat dissipation region and the electrode region, and the outer frame is disposed on the first metal layer in the peripheral region.

As an improved technical scheme, the LD chip is welded and fixed on the first metal layer in the heat dissipation area through a soldering lug, and the positive and negative electrodes of the LD chip are connected with the first metal layer in the same electrode area by using metal wires, respectively.

As an improved technical scheme, both ends of the optical fiber are provided with positioning pieces, the positioning pieces are U-shaped structures matched with the outer diameters of the optical fiber, mounting holes matched with the bottoms of the positioning pieces are formed in the first metal layer, the positioning pieces are inserted into the mounting holes, and the positioning pieces are fixedly bonded with the first metal layer by utilizing nano tin paste.

As an improved technical scheme, the bottom of the reflector is fixedly arranged on the first metal layer through die bond glue.

As an improved technical scheme, the front surface of the fluorescent cover plate is provided with a fluorescent powder layer, the edge position of the back surface of the fluorescent cover plate is provided with a second metal layer, the middle position of the back surface of the fluorescent cover plate is provided with a circular light-transmitting area formed by the second metal layer in a surrounding mode, and the fluorescent cover plate is fixedly bonded with the outer frame through the second metal layer by utilizing nano tin paste.

The invention also discloses a preparation method of the inorganic packaging structure of the LD chip, which comprises the following steps:

s1, providing a ceramic substrate, and forming a through hole on the ceramic substrate to obtain a structure I;

s2, preparing first metal layers on two sides of the structure I respectively to obtain a structure II;

s3, cutting the structure II into a plurality of heat sink units, wherein the first metal layers on two sides of each heat sink unit comprise a heat dissipation area and an electrode area, and one side of each heat sink unit further comprises a peripheral area surrounding the heat dissipation area and the electrode area;

s4, preparing an outer frame at the position of the first metal layer in the peripheral area of the heat sink unit in a welding installation or electroplating mode to obtain a structure III;

s5, mounting an LD chip on one surface of the heat sink unit with the outer frame, welding the LD chip on the first metal layer of the heat dissipation area by using a soldering lug, then routing, and respectively connecting the anode and the cathode of the LD chip with the first metal layer of the same surface electrode area by using a metal wire to obtain a structure IV;

s6, sequentially arranging an optical fiber and a reflector on the light-emitting side of the LD chip to obtain a structure V;

and S7, providing a fluorescent cover plate with a circular light-transmitting area, and covering the fluorescent cover plate on the top of the outer frame.

As a modified solution, in step S2, the preparing the first metal layers on the two sides of the structure I respectively includes:

forming a photoresist layer on one surface of the structure I, patterning the photoresist layer through exposure and development processes, and then performing evaporation or electroplating on one surface of the ceramic substrate with the patterned photoresist layer to plate a first metal layer;

the other side of the structure I is also provided with a patterned photoresist and then is plated with a first metal layer to obtain a structure with the two sides plated with the first metal layers, and the first metal layers at the positions of the through holes are connected through the through holes;

and stripping the photoresist through a photoresist stripping process, and removing the photoresist layer to obtain a structure II.

As a modified solution, in step S5, the soldering the LD chip to the first metal layer of the heat dissipation area by using a solder pad includes:

and placing the soldering lug between the LD chip and the first metal layer of the heat dissipation area, melting the soldering lug under the conditions of 280-320 ℃ and 5-30s by using a reflow soldering technology and nitrogen as protective gas, and then achieving the bonding effect in a slow cooling mode to realize the welding fixation of the LD chip on the first metal layer.

As a modified solution, in step S6, the sequentially disposing an optical fiber and a reflector on the light emitting side of the LD chip includes:

fixing two ends of the optical fiber by using positioning parts with U-shaped structures respectively, wherein the positioning parts are clamped at the two ends of the optical fiber respectively, the bottom of each positioning part is inserted onto the first metal layer and is bonded and fixed with the first metal layer by using nano tin paste, so that the optical fiber is positioned and installed, and a light source of the LD chip passes through the center of the optical fiber after installation;

and placing one side of the reflector with the inclined reflecting surface close to the optical fiber, and fixedly installing the reflector on the first metal layer by using die bond adhesive.

As a modified solution, in step S7, providing a fluorescent cover plate having a circular light-transmitting area, and covering the fluorescent cover plate on the top of the outer frame includes:

plating a second metal layer on the edge of the back of the fluorescent cover plate, making the fluorescent cover plate into a diaphragm pattern with a circular light-transmitting area, covering one side of the fluorescent cover plate with the second metal layer on the top of an outer frame in a matching manner, and bonding and fixing the second metal layer and the outer frame by using nano tin paste.

After the technical scheme is adopted, the invention has the beneficial effects that:

(1) according to the inorganic packaging structure of the LD chip, the LD chip is horizontally placed, and laser is shaped into parallel light through an optical fiber after being emitted through the side face of the LD chip, and then the parallel light is incident on a reflector and is reflected to a fluorescent cover plate at the top through the reflector to excite the fluorescent cover plate to emit white light; compare traditional TO packaging structure, the place that laser can shine all does not have organic glue, has realized the most genuine inorganic encapsulation, and the LD chip can not contact steam and organic composition, and life prolongs greatly, and this packaging structure volume is littleer, can use in the small-size module.

(2) The positive and negative electrodes of the LD chip are converted to the back surface of the ceramic substrate through the routing and the first metal layer of the electrode area, and the LD chip can be used through surface mount welding, so that the LD chip is simpler and more convenient to install and use.

(3) Through preparation first metal level on ceramic substrate to utilize the soldering lug to realize that the bonding of LD chip on first metal level is fixed, the bonding is firm reliable, and the soldering lug replaces traditional silver-colored glue, and the heat conductivity is good, makes whole chip packaging structure's radiating effect improve greatly, and then effectively improves the performance and the life of LD chip.

(4) The optical fiber is fixed by the positioning piece, the positioning piece is inserted into the first metal layer through the mounting hole in a positioning mode, the nano tin paste is bonded and fixed with the first metal layer, the optical fiber is simple and convenient to install and fix, the optical fiber can be accurately positioned and installed, and reliable guarantee is provided for effective shaping of light emitted by an LD chip.

(5) The light diaphragm structure pattern's that is equipped with this fluorescence apron, the second metal level utilize nanometer tin cream and frame bonding fixed, not only be convenient for realize that the lid on the frame closes fixedly, and the circular printing opacity district that forms can play the effect of integer light, covers the miscellaneous light outside the main facula, and the phosphor layer that fluorescence apron has adopts fluorescence functional material to convert monochromatic laser into white light and sends.

(6) The preparation method of the inorganic packaging structure of the LD chip can realize the high-efficiency preparation of the heat sink unit and the high-efficiency and orderly packaging of the LD chip, and the preparation method is simple.

Drawings

In order to more clearly illustrate the detailed description of the invention or the technical solutions in the prior art, the drawings that are needed in the detailed description of the invention or the prior art will be briefly described below. Throughout the drawings, like elements or portions are generally identified by like reference numerals. In the drawings, elements or portions are not necessarily drawn to scale.

FIG. 1 is a schematic structural view of structure I of the present invention;

FIG. 2 is a schematic structural view of structure II of the present invention;

FIG. 3 is a schematic structural diagram of a heat sink unit according to the present invention;

FIG. 4 is a schematic structural view of structure III of the present invention;

FIG. 5 is a schematic diagram of structure IV of the present invention;

FIG. 6 is a schematic structural view of structure V of the present invention;

FIG. 7 is a schematic view of the structure of the fluorescent cover plate of the present invention;

FIG. 8 is a schematic structural diagram of an inorganic package of an LD chip according to the present invention;

FIG. 9 is a schematic view of the internal structure of the inorganic package of the LD chip according to the present invention;

FIG. 10 is a schematic cross-sectional view of an inorganic package for an LD chip according to the present invention;

FIG. 11 is a flow chart of the method for manufacturing the inorganic package of the LD chip according to the present invention;

reference numerals: 1-a ceramic substrate; 101-a through hole; 2-a first metal layer; 201-bar-shaped identification holes; 202-mounting holes; 3-an outer frame; 4-LD chip; 5-a metal wire; 6-an optical fiber; 7-a positioning member; 8-a mirror; 9-fluorescent cover plate; 901-a phosphor layer; 902-a second metal layer; 903-circular light-transmitting area.

Detailed Description

The invention is further illustrated by the following specific examples. The use and purpose of these exemplary embodiments are to illustrate the present invention, not to limit the actual scope of the present invention in any way, and not to limit the scope of the present invention in any way.

As shown in fig. 1 to 10, the present embodiment provides an inorganic package structure of an LD chip, including a ceramic substrate 1, wherein both sides of the ceramic substrate 1 are plated with first metal layers 2, each first metal layer 2 includes a heat dissipation area and an electrode area, and the first metal layers 2 of the electrode areas on both sides of the ceramic substrate 1 are connected, wherein an LD chip 4 is mounted on the first metal layer 2 of one heat dissipation area, and the positive and negative electrodes of the LD chip 4 are respectively connected to the first metal layers 2 of the same electrode area.

The light-emitting side of the LD chip 4 is sequentially provided with an optical fiber 6 and a reflector 8, the optical fiber 6 corresponds to the light source emitting point of the LD chip 4, and one side of the reflector 8 close to the optical fiber 6 is an inclined reflecting surface.

One side of the ceramic substrate 1 is also provided with an outer frame 3, a fluorescent cover plate 9 is covered on the top of the outer frame 3 in a matching way, the fluorescent cover plate 9 is of a diaphragm structure, and the ceramic substrate 1, the outer frame 3 and the fluorescent cover plate 9 form a packaging area for accommodating an internal light path device.

In this embodiment, the ceramic substrate 1 is an AlN-based ceramic substrate, which has better thermal conductivity and better heat dissipation than alumina, and the ceramic substrate 11 has a thickness of 200-500 μm.

In order to realize the connection between the first metal layers 2 of the electrode areas on the two sides of the ceramic substrate 1, through holes 101 are formed at both ends of the ceramic substrate 1, and the first metal layers 2 of the electrode areas on the two sides of the ceramic substrate 1 are connected through the through holes 101 respectively.

In this embodiment, the through holes 101 are formed in a plurality to ensure effective connection between the first metal layers 2.

In this embodiment, the bar-shaped identification hole 201 is formed at one end of the first metal layer 2 connected to the negative electrode of the LD chip 4, so that the positive and negative electrodes can be distinguished when the chip with the package structure is used.

The first metal layer 2 on one surface of the ceramic substrate 1 further comprises a peripheral area, the peripheral area surrounds the heat dissipation area and the electrode area, and the outer frame 3 is arranged on the first metal layer 2 in the peripheral area; in this embodiment, the outer frame 3 is prepared on the first metal layer 2 in the peripheral region by electroplating, and has good sealing performance.

In this embodiment, the first metal layer 2 of the heat dissipation region on one side of the ceramic substrate 1 and the first metal layer 2 of the electrode region for connecting with the anode of the LD chip 4 are integrally connected.

In this embodiment, the LD chip 4 is soldered and fixed on the first metal layer 2 in the heat dissipation area by solder bumps, which are pre-formed Au80% and Sn20% solder bumps.

In this embodiment, when the LD chip 4 is mounted on the first metal layer 2 in the heat dissipation area, the side edge is flush with the edge of the first metal layer 2, so as to realize the positioning and mounting of the LD chip 4, and ensure the accuracy of the mounting position of the LD chip 4.

In this embodiment, the positive electrode and the negative electrode of the LD chip 4 are respectively connected to the first metal layer 2 in the electrode area on the same side by the metal wire 5, the metal wire 5 is a gold wire of 40-60 μm, the positive electrode and the negative electrode of the LD chip 4 are connected to the first metal layer 2 on the same side by the metal wire 5, and the positive electrode and the negative electrode of the LD chip 4 are respectively transferred to the first metal layer 2 in the electrode area on the other side, which is convenient for pasting.

In order to realize the installation and fixation of the optical fiber 6 and ensure that the light source of the LD chip 4 passes through the center of the optical fiber 6 after installation, positioning pieces 7 are arranged at two ends of the optical fiber 6, the positioning pieces 7 are U-shaped structures matched with the outer diameter of the optical fiber 6, an installation hole 202 matched with the bottom of the positioning piece 7 is formed in the first metal layer 2, and the positioning piece 7 is inserted into the installation hole 202 and is fixedly bonded with the first metal layer 2 by utilizing nano tin paste; the optical fiber 6 is fixedly installed by the positioning piece 7, the positioning piece 7 is inserted into the first metal layer 2 through the installation hole 202 in a positioning mode and is fixedly bonded with the first metal layer 2 by the aid of the nano solder paste, the optical fiber 6 is easily and conveniently installed and fixed, accurate positioning installation can be achieved, and reliable guarantee is provided for effective shaping of light emitted by the LD chip 4.

In this embodiment, the bottom of the reflector 8 is fixedly mounted on the first metal layer 2 through a die bond, the reflector 8 is a silicon base with an inclined surface, and a layer of DBR is prepared on the inclined surface to form a reflecting surface.

The front surface of the fluorescent cover plate 9 is provided with a fluorescent powder layer 901, the edge position of the back surface of the fluorescent cover plate 9 is provided with a second metal layer 902, the middle position of the back surface of the fluorescent cover plate 9 is provided with a circular light-transmitting area 903 formed by the second metal layer 902 in a surrounding mode, and the fluorescent cover plate 9 is fixedly bonded with the outer frame 3 through the second metal layer 902 by utilizing nano tin paste; the fluorescent cover plate 9 with the diaphragm structure and the second metal layer 902 are bonded and fixed with the outer frame 3 by using the nano tin paste, so that the cover on the outer frame 3 is convenient to cover and fix, the formed circular light-transmitting area 903 can play a role of shaping light, stray light outside a main light spot is shielded, and a fluorescent powder layer 901 of the fluorescent cover plate 9 adopts a fluorescent functional material to convert monochromatic laser into white light to emit the white light.

In this embodiment, the first metal layer 2 and the second metal layer 902 are both a composite structure of Cr, Al, Ti, Pt, Au or Ni, Al, Ti, Pt, Au, and the thickness of the metal layers is 40-60 μm.

The embodiment also discloses a preparation method of the inorganic encapsulation structure of the LD chip, as shown in fig. 11, including the following steps:

step S1: providing a ceramic substrate 1, and forming a through hole 101 in the ceramic substrate 1 to obtain a structure I, as shown in FIG. 1;

in this step, the apparatus and the opening process for opening the ceramic substrate 1 are well known to those skilled in the art and will not be described herein.

Step S2: respectively preparing first metal layers 2 on two sides of the structure I to obtain a structure II, as shown in FIG. 2;

in the step, firstly, a photoresist layer is formed on one surface of the structure I, the photoresist layer is patterned through exposure and development processes, then the surface of the ceramic substrate 1 with the patterned photoresist layer is subjected to evaporation or electroplating, a first metal layer 2 is plated, and the patterned photoresist is a conventional process and is not described in detail herein;

then, patterning photoresist is made on the other surface of the structure I, and then a first metal layer 2 is plated to obtain a structure with two surfaces plated with the first metal layer 2, wherein the first metal layers 2 at the positions of the through holes 101 are connected through the through holes 101; during the metal layer plating process, metal is plated in the through holes 101, so that the metal layers on two sides of the ceramic substrate 1 are connected;

and finally, carrying out photoresist stripping by a photoresist stripping process to remove the photoresist layer, wherein when the photoresist is stripped, the metal layer plated on the photoresist is removed along with the photoresist stripping, and the metal layer plated on the ceramic substrate 1 is left to obtain a structure II.

Step S3: cutting the structure II into a plurality of heat sink units, wherein the first metal layers 2 on two sides of each heat sink unit respectively comprise a heat dissipation area and an electrode area, and one side of each heat sink unit also comprises a peripheral area surrounding the heat dissipation area and the electrode area, as shown in FIG. 3;

in this step, it is well known to those skilled in the art that a cutting device is used to cut the ceramic substrate 1, and details are not described herein, the cut single heat sink unit is used to implement the encapsulation of the LD chip 4, and the heat dissipation area in the middle of the heat sink unit is the most thick area of the metal layer to implement effective heat conduction and heat dissipation.

Step S4: preparing an outer frame 3 at the position of the first metal layer 2 in the peripheral area of the heat sink unit by welding or electroplating to obtain a structure III, as shown in FIG. 4;

in this step, the outer frame 3 is directly prepared on the first metal layer 2 in the peripheral area by electroplating, and the firmness and the sealing performance are better compared with the mode of bonding on the first metal layer 2.

Step S5: mounting an LD chip 4 on one surface of the heat sink unit with the outer frame 3, welding the LD chip 4 on the first metal layer 2 of the heat dissipation area by using a soldering lug, then routing, and respectively connecting the positive and negative electrodes of the LD chip 4 with the first metal layer 2 of the same surface electrode area by using a metal wire 5 to obtain a structure IV, as shown in FIG. 5;

in the step, the soldering lug is placed between the LD chip 4 and the first metal layer 2 of the heat dissipation area, the soldering lug is melted under the conditions of 280 plus materials and 320 ℃ for 5-30s by using a reflow soldering technology and using nitrogen as protective gas, and then the bonding effect is achieved by slowly cooling, so that the welding and fixing of the LD chip 4 on the first metal layer 2 are realized;

in this embodiment, the temperature for welding the LD chip 4 is controlled to be about 300 ℃, the heating time is 25s, the gold-tin soldering sheet can be effectively melted, and the efficient welding of the LD chip 4 is realized.

Step S6: an optical fiber 6 and a reflector 8 are sequentially arranged on the light emitting side of the LD chip 4 to obtain a structure V, as shown in fig. 6;

in the step, two ends of an optical fiber 6 are respectively fixed by using a positioning piece 7 with a U-shaped structure, the positioning pieces 7 are respectively clamped at two ends of the optical fiber 6, the bottom of the positioning piece 7 is inserted onto the first metal layer 2 and is fixedly bonded with the first metal layer 2 by using nano tin paste, so that the positioning and the installation of the optical fiber 6 are realized, and the light source of the LD chip 4 passes through the center of the optical fiber 6 after the installation;

one side of the reflector 8 with the inclined reflecting surface is arranged close to the optical fiber 6, and the reflector 8 is fixedly arranged on the first metal layer 2 by utilizing die bond glue.

Step S7: a fluorescent cover plate 9 having a circular transparent area 903 is provided, and the fluorescent cover plate 9 is covered on the top of the outer frame 3, as shown in fig. 7 to 10 together.

In the step, a second metal layer 902 is plated on the edge of the back of the fluorescent cover plate 9, the fluorescent cover plate 9 is made into a diaphragm type with a circular light-transmitting area 903, one side of the fluorescent cover plate 9 with the second metal layer 902 is adapted to cover the top of the outer frame 3, and the second metal layer 902 and the outer frame 3 are bonded and fixed by using nano tin paste.

The preparation method of the LD chip 4 inorganic packaging structure based on the steps can realize the high-efficiency preparation of the heat sink unit and the high-efficiency and orderly packaging of the LD chip 4, the preparation method is simple, the prepared LD chip 4 inorganic packaging structure is characterized in that the LD chip 4 is horizontally placed, laser is shaped into parallel light through the optical fiber 6 after being emitted from the side surface of the LD chip 4, the parallel light is emitted to the reflector 8, and the parallel light is reflected to the fluorescent cover plate 9 at the top through the reflector 8 to excite the emitting of white light; compare traditional TO packaging structure, the place that laser can shine does not all have organic glue, has realized the most genuine inorganic encapsulation, and LD chip 4 can not contact steam and organic composition, and life prolongs greatly, and this packaging structure volume is littleer, can use in the small-size module.

In addition, the anode and the cathode of the LD chip 4 are converted to the back of the ceramic substrate 1 through the routing and the first metal layer 2 in the electrode area, and the LD chip can be used through surface mount welding, so that the LD chip is simpler and more convenient to install and use; through preparing first metal level 2 on ceramic substrate 1 to utilize the soldering lug to realize that the bonding of LD chip 4 on first metal level 2 is fixed, the bonding is firm reliable, and the soldering lug replaces traditional silver-colored glue, and the heat conductivity is good, makes 4 packaging structure's of whole chip radiating effect improve greatly, and then effectively improves LD chip 4's performance and life.

It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should also be understood that various alterations, modifications and/or variations can be made to the present invention by those skilled in the art after reading the technical content of the present invention, and all such equivalents fall within the protective scope defined by the claims of the present application.

Claims

1. An inorganic packaging structure of an LD chip is characterized by comprising a ceramic substrate, wherein two sides of the ceramic substrate are plated with first metal layers, each first metal layer comprises a heat dissipation area and an electrode area, the first metal layers of the electrode areas on the two sides of the ceramic substrate are connected, an LD chip is mounted on the first metal layer of the heat dissipation area on one side, the LD chip is fixedly welded on the first metal layer of the heat dissipation area through a soldering lug, the soldering lug adopts preformed gold-tin soldering lugs of Au80% and Sn20%, and the anode and the cathode of the LD chip are respectively connected with the first metal layers of the electrode areas on the same side through metal wires;

the LED chip comprises an LD chip and is characterized in that an optical fiber and a reflector are sequentially arranged on the light-emitting side of the LD chip, positioning parts are arranged at two ends of the optical fiber, the positioning parts are of U-shaped structures matched with the outer diameter of the optical fiber, mounting holes matched with the bottoms of the positioning parts are formed in a first metal layer, the positioning parts are inserted into the mounting holes and are fixedly bonded with the first metal layer by using nano tin paste, the optical fiber and a light source emitting point of the LD chip are correspondingly arranged, an inclined reflecting surface is arranged at one side of the reflector close to the optical fiber, and the bottom of the reflector is fixedly mounted on the first metal layer through crystal fixing glue;

2. The LD chip inorganic package structure of claim 1, wherein: through holes are formed in two end parts of the ceramic substrate, and the first metal layers in the electrode areas on the two sides of the ceramic substrate are connected through the through holes respectively;

the first metal layer on one surface of the ceramic substrate further comprises a peripheral area, the peripheral area surrounds the heat dissipation area and the electrode area, and the outer frame is arranged on the first metal layer in the peripheral area.

3. The LD chip inorganic package structure of claim 2, wherein: the front surface of the fluorescent cover plate is provided with a fluorescent powder layer, the edge position of the back surface of the fluorescent cover plate is provided with a second metal layer, the middle position of the back surface of the fluorescent cover plate is provided with a circular light-transmitting area formed by the second metal layer in a surrounding mode, and the fluorescent cover plate is fixedly bonded with the outer frame through the second metal layer by means of nano tin paste.

4. The preparation method of the inorganic package structure of the LD chip based on claim 1, characterized by comprising the following steps:

5. The method for preparing an inorganic package structure of an LD chip as claimed in claim 4, wherein the step S2, the step of preparing the first metal layers on both sides of the structure I respectively comprises:

6. The method for preparing an inorganic package structure of LD chip according to claim 5, wherein the step S5, the soldering the LD chip to the first metal layer of the heat dissipation area with the solder pad includes:

7. The method for preparing an inorganic package structure of an LD chip as claimed in claim 6, wherein the step S6 of disposing an optical fiber and a reflector in order on the light emitting side of the LD chip comprises:

8. The method for preparing an inorganic package structure of LD chip as claimed in claim 7, wherein in step S7, providing a fluorescent cover plate with a circular transparent area, and covering the fluorescent cover plate on top of the outer frame comprises: