TWI556361B - Laser chip package structure - Google Patents

Description

Laser chip package structure

The present invention relates to a chip package structure, and more particularly to a laser chip package structure.

At present, the application of laser is more and more widely used in the future. It will be widely used in laser projection systems and optical communication transmission systems. The output power of laser is controlled by input current. The output power of laser will increase with the increase of temperature. small. When the electronic components are operated, the temperature will be higher and higher, so that when the input current is constant, the laser output optical power will decrease as the temperature increases. When laser is used in optical communication, as the temperature rises, the output power becomes smaller, which causes an increase in the bit error rate.

In view of this, it is necessary to provide a laser chip package structure that can improve the heat dissipation effect of the laser wafer.

A laser chip package structure comprising:

a circuit substrate;

a pad formed on the circuit substrate having a bearing surface facing away from the circuit substrate;

a double-sided adhesive film includes a first rubber surface adhered to the bearing surface, and a second rubber surface opposite to the first rubber surface;

a laser wafer attached to the second adhesive surface of the double-sided adhesive film, the laser wafer having a light-emitting surface, the light-emitting surface facing away from the second rubber surface of the double-sided adhesive film;

a heat dissipating gel coated on the bearing surface of the liner and adhered around the laser wafer and the double-sided adhesive film, the heat-dissipating gel facing away from the top surface of the liner is lower than the laser wafer The light emitting surface exposes a light emitting surface of the laser wafer, and the heat dissipating gel is silver paste.

In contrast to the prior art, the heat dissipating gel is coated on the surface of the pad and adhered around the laser wafer and the double-sided adhesive film, and the heat dissipating gel has a good heat dissipation effect. The laser wafer can accelerate the heat dissipation speed through the heat dissipating gel.

The technical solution will be further described in detail below with reference to the accompanying drawings and embodiments.

Referring to FIG. 1 , a laser chip package structure 100 according to an embodiment of the present invention includes a circuit substrate 10 , a gasket 20 , a double-sided adhesive film 30 , a laser wafer 40 , and a heat dissipation gel 50 .

The laser wafer 40 is a laser diode (LD), which is applied to an optical fiber connection transmission system. The laser wafer 40 is a microchip, and a common size is about 200 um in length and width. The laser wafer 40 has a light emitting surface 42 for emitting laser light. In the embodiment, the light emitting surface 42 is located on one of the top surfaces of the laser wafer 40.

The circuit substrate 10 is used to drive and control the operation of the laser wafer 40. The circuit board 10 can be made of a material such as glass fiber, reinforced plastic or ceramic.

The pad 20 is formed at a position where the circuit substrate 10 is to be packaged with the laser wafer 40, and the area of the pad 20 is larger than the area of the laser wafer 40. The spacer 20 is made of a conductive metallic material such as copper, nickel, gold, silver or an alloy thereof, and can be formed on the circuit substrate 10 by soldering. The gasket 20 has a bearing surface 22 facing away from the circuit substrate 10. The laser wafer 40 can be wire bonded to the carrying surface 22 of the gasket 20 and electrically connected to the circuit substrate 10 through the gasket 20.

The double-sided adhesive film 30 includes a first adhesive surface 32 adhered to the bearing surface 22 of the liner 20, and a second adhesive surface 34 opposite the first adhesive surface 32. The length dimension of the double-sided adhesive film 30 is not less than the length dimension of the laser wafer 40, and the two are equivalent, that is, substantially equal to. The laser wafer 40 is attached to the second rubber surface 34 of the double-sided adhesive film 30. The top surface of the light-emitting surface 42 of the laser wafer 40 is facing upward, that is, facing away from the double-sided adhesive film 30.

The heat dissipating gel 50 is coated on the bearing surface 22 of the gasket 20 and adhered around the laser wafer 40 and the double-sided adhesive film 30. In the embodiment, the heat dissipating gel 50 surrounds the laser wafer 40 and the double-sided adhesive film 30 around 360 degrees. The top surface 52 of the heat dissipating gel 50 facing away from the spacer 20 is lower than the light emitting surface 42 of the laser wafer 40 to expose the light emitting surface 42 of the laser wafer 40. In this embodiment, the height of the heat dissipating gel 50 in the direction perpendicular to the bearing surface 22 is greater than the height of the double-sided adhesive film 30 and less than the height of the double-sided adhesive film 30 and the height of the laser wafer 40. with.

In the embodiment, the double-sided adhesive film 30 and the heat dissipation colloid 50 are both silver paste.

In other embodiments, only the heat dissipating gel 50 may be made of silver glue, and the double-sided adhesive film 30 may be made of epoxy resin or other adhesive material.

The heat dissipation colloid of the laser chip package structure 100 provided by the present invention is coated on the surface of the pad and adhered around the laser wafer and the double-sided adhesive film, and the heat dissipating gel has good silver paste. The heat dissipation effect of the laser wafer can be accelerated by the heat dissipating gel.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

100. . . Laser chip package structure

10. . . Circuit substrate

20. . . pad

30. . . Double-sided adhesive film

40. . . Laser chip

50. . . Heat sink

42. . . Luminous surface

twenty two. . . Bearing surface

32. . . First rubber surface

34. . . Second rubber surface

52. . . Top surface of the heat sink

1 is a cross-sectional view showing a laser chip package structure according to an embodiment of the present invention.

100. . . Laser chip package structure

10. . . Circuit substrate

20. . . pad

30. . . Double-sided adhesive film

40. . . Laser chip

50. . . Heat sink

42. . . Luminous surface

twenty two. . . Bearing surface

32. . . First rubber surface

34. . . Second rubber surface

52. . . Top surface of the heat sink

Claims (6)

A laser chip package structure comprising:
a circuit substrate;
a pad formed on the circuit substrate having a bearing surface facing away from the circuit substrate;
a double-sided adhesive film includes a first rubber surface adhered to the bearing surface, and a second rubber surface opposite to the first rubber surface;
a laser wafer is attached to the second rubber surface of the double-sided adhesive film, the laser wafer has a light-emitting surface for emitting laser light, the light-emitting surface faces away from the second rubber surface of the double-sided adhesive film; and a heat dissipation a colloid is coated on the bearing surface of the liner and adhered around the laser wafer and the double-sided adhesive film, and a top surface of the heat-dissipating gel facing away from the liner is lower than a light emission of the laser wafer The surface is exposed to expose a light emitting surface of the laser chip, and the heat dissipating gel is a silver paste. The laser chip package structure of claim 1, wherein the material of the spacer is selected from the group consisting of copper, nickel, gold, silver or alloys thereof. The laser chip package structure of claim 1, wherein: the height of the heat dissipating gel along the vertical bearing surface is less than the sum of the height of the double-sided adhesive film and the height of the wafer. The laser chip package structure of claim 1, wherein: the double-sided adhesive film has a length dimension equivalent to a length dimension of the wafer. The laser chip package structure of claim 1, wherein the double-sided adhesive film is silver paste. The laser chip package structure of claim 1, wherein: the area of the pad is larger than an area of the laser chip.