TWI423483B - Optical diode package structure - Google Patents

Description

Photodiode package structure

The present invention is a photodiode package structure, especially an optical diode package structure applied to a photodiode die.

Light Emitting Diode (LED) is a kind of light-emitting device that can directly convert electrical energy into visible light and radiant energy. The principle of light-emitting is to apply voltage to the two terminals of the positive and negative electrodes in the semiconductor. When the current passes, the electron is passed. When combined with a hole, the remaining energy is released in the form of light. Depending on the material used, the level of the energy level causes the photon energy to produce light of different wavelengths. Therefore, the light-emitting diode (LED) usually has an operating voltage. Low performance, low power consumption, high luminous efficiency, short response time, pure light color, firm structure, impact resistance, vibration resistance, stable and reliable performance, light weight, small size and low cost. The development can be said to be leaps and bounds, and it is now able to mass produce high-brightness, high-performance products of various colors in the entire visible spectrum. The production process of light-emitting diodes (LEDs) in the industry can be mainly divided into the production of light-emitting diode (LED) substrate wafers and substrates, and the midstream industry is the design and manufacture of light-emitting diode (LED) chips. The downstream is the LED package and test. The package of the LED is an important key technology that affects whether the finished LED is excellent.

The light emitting diode package structure is a single or multiple light emitting diodes (LED) is fixed on the support or the substrate, and the positive and negative electrodes of the light-emitting diode (LED) are connected to the electrodes on the bracket or the substrate by wire bonding or eutectic, and the method of dispensing or molding is used. The light emitting diode (LED) is encapsulated with epoxy or silicone. Please refer to the first figure, which is a schematic diagram of a light-emitting diode package structure having a lens structure. As can be clearly seen from the figure, the LED package structure 1 includes a package base 10 and a lens structure 11 , wherein the package base 10 has a bearing space 12 for carrying a light-emitting diode. The lens structure 11 is bonded to the light-emitting surface 101 of the package base 10 through an adhesive 13 (for example, Silicone or Epoxy). However, when the lens structure 11 and the package base 10 are joined by the light-emitting diode package structure 1 having a lens structure, it often happens that the lens structure 11 cannot accurately align the light-emitting surface 101 of the package base 10. The center point (as indicated by the triangle symbol in the figure) causes an offset between the lens structure 11 and the package base 10, or the adhesive 13 is applied during the bonding process. The unevenness causes a situation in which the lens structure 11 and the package base 10 are inclined.

As shown in the second figure (a), (b) and (c), the lens structure 11 is bonded to the package base 10 to generate an offset or tilt diagram. As shown in the second figure (a) (b), during the bonding of the lens structure 11 to the package base 10, as shown in the second figure (a), the lens structure 11 cannot accurately align the package. When the center point of the light-emitting surface 101 of the susceptor 10 (marked by the triangular symbol), as shown in the second figure (b), the lens structure 11 is generated to be unidirectional with respect to the light-emitting surface 101 of the package base 10. Linear offset (in the X direction) or in both directions (X direction and Y direction). As shown in the second figure (c), when joined During the process, the bonding adhesive 13 is deformed due to uneven application, and the lens structure 11 is caused to have a skew angle with respect to the light-emitting surface 101 of the package base 10. When the lens structure 11 and the package base 10 are not properly bonded during the bonding process, the relative positional deviation between the LED die 100 and the lens structure 11 is excessively large, resulting in a decrease in luminous efficiency and light. Type change. In addition, after the lens structure 11 is bonded to the package base 10, the following situation occurs. As shown in the second figure (d), it can be clearly seen that the lens structure 11 is inscribed in When the package base 10 is rounded in four sides, the lens structure 11 cannot cover the package base 10 (the four corners of the package base are exposed outside the lens structure 11 as shown). The area of the package base 10 is wasted; another case is a top view shown in FIG. 2(e), in order to enable the lens structure 11 to completely cover the package base 10, thereby increasing the lens structure 11 The area of the lens structure 11 is wasted by the fact that a portion of the lens structure 11 is beyond the package base 10. Both of the above cases will result in an increase in production costs.

In order to improve the alignment and the cost of manufacturing due to the relative displacement between the lens structure and the package base, a micro lens optical system that can be formed in combination with a plurality of optical elements has been developed. As shown in the third (a) to (e), the spherical lens 200 is first formed by a Reflow process (Fig. 3(a)); then a polymer material 201 is cast (Cast) at The spherical lens in the third figure (a) (third figure (b)); after curing, a polymer material mold 202 is obtained (third figure (c)); and the microlens array is fabricated by spin coating. The material of 203 is coated on the polymer material mold 202 obtained in the third figure (c). (Fig. 3(d)); finally, after performing a stripping process, a microlens array 203 having elasticity is obtained. After the description of the microlens array 203 is described above, it can be clearly seen that the conventional microlens array 203 has to be additionally fabricated through a series of casting processes, and then the individual lenses of the microlens array 203 are The microlens structure is bonded to a package base of a single light emitting diode to form a package structure as shown in the first figure, although the microlens array 203 can effectively improve the alignment caused by the relative displacement between the lens structure and the package base. And fixed problems, but such a complicated process will inevitably lead to an increase in production costs. Therefore, how to improve the above-mentioned defects is the most important purpose of the development of this case.

The present invention is an optical diode package structure applied to a photodiode die. The package structure comprises: a substrate having a first surface; a bearing space having a top opening at the first of the substrate a surface, a bottom portion thereof for carrying the photodiode crystal grain; and an optical material layer formed in the bearing space and covering the photodiode crystal grain and having a microlens array structure, wherein the microlens The array structure is located above the crystal diode of the photodiode to transmit the light emitted by the photodiode, and the shape of the microlens and the arrangement of the array can effectively improve the light efficiency and change the optical mode.

According to the above concept, the photodiode package structure of the present invention, wherein the substrate is a germanium (100) lattice direction, a (110) lattice direction or a (111) lattice direction.

According to the above concept, the photodiode package structure of the present invention, wherein the substrate is a ceramic substrate of aluminum oxide or aluminum nitride material.

According to the above concept, the photodiode package structure of the present invention, wherein the substrate is a metal substrate made of an aluminum metal or a copper metal.

According to the above concept, the optical diode package structure of the present invention, wherein the bearing space is surrounded by a plurality of inclined faces, and the inclined faces are less than 90 degrees from the bottom of the carrying space.

According to the above concept, the photodiode package structure of the present invention, wherein the shape of the bearing space is a cone shape, a positive cubic shape, a rectangular shape, a half elliptical shape or a half conical shape.

According to the above concept, the photodiode package structure of the present invention further comprises a via hole, wherein the bottom opening is located on a second surface of the substrate, and the top of the via hole is connected to the bottom of the carrying space.

According to the above concept, the photodiode package structure of the present invention, wherein the optical material layer and the microlens array structure are optical colloids having a certain light transmittance or a thermoplastic type.

According to the above concept, the photodiode package structure of the present invention, wherein the optical material layer is a thermocolloid or a thermoplastic optical colloid having a certain light transmittance, and the microlens array structure is a photosensitive Material, a thermoset material or a thermoplastic material.

According to the above concept, the photodiode package structure of the present invention, wherein the microlens array structure is completed by pressing a mold core onto the optical material layer.

According to the above concept, the photodiode package structure of the present invention, wherein the microlens array structure is composed of a plurality of microlens structures, and the The microlens structure may be a hemispherical three-dimensional microstructure with an arc curved upward or a semi-elliptical three-dimensional microstructure with two axial lengths.

According to the above concept, the photodiode package structure described in the present invention, wherein the microlens structure may be a circular hemispherical three-dimensional microstructure or a semi-elliptical three-dimensional microstructure having two axial lengths.

According to the above concept, the photodiode package structure of the present invention, wherein the microlens structure can be a trihedral pyramid microstructure or a tetrahedral pyramid microstructure.

According to the above concept, the photodiode package structure of the present invention, wherein the microlens array structure is located on or in the first surface of the substrate.

According to the above concept, the photodiode package structure used in the present invention is a photodiode or a laser diode.

The other aspect of the present invention is a photodiode package structure applied to a photodiode die. The package structure includes: a substrate having a first surface; a bearing space having a top opening at the substrate The first surface has a bottom portion for carrying the photodiode grains; an optical material layer formed in the bearing space and covering the photodiode crystal grains; and a microlens array structure Connecting to the optical material layer and above the photodiode die for transmitting light emitted by the photodiode and defining a light pattern.

According to the above concept, in another aspect of the invention, the photodiode package structure, wherein the substrate is a germanium (100) lattice direction, a (110) lattice direction or a (111) lattice direction.

According to the above concept, in another aspect of the invention, the photodiode package structure, wherein the substrate is a ceramic substrate of aluminum oxide or aluminum nitride material.

According to the above concept, in another aspect of the invention, the photodiode package structure, wherein the substrate is a metal substrate made of an aluminum metal or a copper metal.

According to the above concept, in the photodiode package structure of the present invention, the bearing space is surrounded by a plurality of inclined faces, and the inclined faces are less than 90 degrees from the bottom of the carrying space.

According to the above concept, in the photodiode package structure according to another aspect of the present invention, the shape of the bearing space is a cone shape, a positive cubic shape, a rectangular shape, a half elliptical shape or a half conical shape.

According to the above concept, the photodiode package structure of the present invention further includes a via hole, wherein the bottom opening is located on a second surface of the substrate, and the top of the via hole is connected to the bottom of the carrying space. .

According to the above concept, the photodiode package structure of the present invention, wherein the optical material layer and the microlens array structure are optical colloids having a certain light transmittance or a thermoplastic type.

According to the above concept, the photodiode package structure according to another aspect of the present invention, wherein the optical material layer is a thermocolloid or a thermoplastic optical colloid having a certain light transmittance, and the microlens array structure is It is a photosensitive material, a thermosetting material or a thermoplastic material.

According to the above concept, in the photodiode package structure of the present invention, the microlens array structure can be bonded to the first surface of the substrate and the optical material layer after dry molding.

According to the above concept, the photodiode package junction described in another aspect of the present invention The microlens array structure is composed of a plurality of microlens structures, and the microlens structures may be a circular arc curved upward one hemispherical three-dimensional microstructure or two axial lengths unequal one semi-elliptical three-dimensional micro structure.

According to the above concept, the photodiode package structure according to another aspect of the present invention, wherein the microlens structure can be a circular arc curved downward one hemispherical three-dimensional microstructure or two axial lengths of one semi-elliptical three-dimensional micro structure.

According to the above concept, the photodiode package structure according to another aspect of the present invention, wherein the microlens structure may be a trihedral pyramid microstructure or a tetrahedral pyramid microstructure.

According to the above concept, a photodiode package structure according to another aspect of the invention, wherein the microlens array structure is located on or in the first surface of the substrate.

According to the above concept, the photodiode package structure used in another aspect of the present invention is a light emitting diode or a laser diode.

Please refer to the fourth figure, which is a schematic diagram of a first preferred embodiment of a photodiode package structure developed to improve the defect of the conventional photodiode package structure, and the package structure described in the present application is applied to The encapsulation process of the light-emitting diode (LED) or a laser diode 300 of the laser diode. As can be clearly seen from the figure, the photodiode package structure 3 of the present invention includes a substrate 30 having a first surface 301 and a second surface 302, a bearing space 31, and a via hole. 32, 33, an optical material layer 34 and a microlens array structure 35, wherein the substrate 30 is a (100) lattice direction, a (110) lattice direction or a (111) lattice direction of the germanium semiconductor substrate Such a semiconductor substrate can provide heat dissipation with high thermal conductivity, and the material of the substrate 30 can also be made of a ceramic substrate made of an aluminum oxide or an aluminum nitride material or one of aluminum metal and copper metal. The metal substrate can also provide heat dissipation with high thermal conductivity; the bearing space 31 is mainly formed by a plurality of inclined surfaces 306, and the top opening is located on the side of the first surface 301 of the substrate 30, and the bottom of the bearing space 31 The bottom of the via holes 32, 33 is located on the side of the second surface 302 of the substrate 30, and the tops of the via holes 32, 33 are connected to the bearing space 31. The bottom of the optical diode package structure of the present invention is that the optical material layer 34 is covered in the bearing space 31, and the optical material layer is covered on the photodiode die 300. 34 is connected to the micro a mirror array structure 35, the microlens array structure 35 is located above the photodiode die 300, and is mainly used to transmit light emitted by the photodiode die 300 while passing through a single microlens shape and array arrangement. The way can effectively improve the light extraction efficiency and change the light type. The photodiode package structure described in the present application will be described in detail below.

According to the above technical description, the bearing space 31 and the via holes 32, 33 generally located on the first surface 301 and the second surface 302 of the substrate 30 are via the first surface 301 of the substrate 30 and the The second surface 302 is etched, and the bearing space 31 is formed on the first surface 301 and the second surface 302 at an angle of less than 90 degrees between the bottom surface and the inclined surface 306 according to the lattice characteristics of the substrate 30. The via holes 32, 33, The bearing space surrounded by the plurality of inclined faces 306 may have a shape of a cone shape, a positive cubic shape, a rectangular shape, a half elliptical shape or a half conical shape. The optical material layer 34 is an optical colloid having a certain light transmittance (such as: silicone rubber, epoxy resin) or a thermoplastic type (such as a high glass transition temperature polyester). The lens array structure 35 is a photosensitive material (eg, photoresist), a thermoset material, or a thermoplastic material.

Referring to FIG. 5(a)-(c), FIG. 5 is a flow chart showing a method for fabricating the microlens array structure 35 included in the photodiode package base structure 3 described in the first preferred embodiment. . As can be clearly seen from the figure, the microlens array structure 35 is mainly completed by a die-compression forming process, and the flow of the steps can be clearly seen from the fifth figure (a) to (c), firstly as As shown in the fifth figure (a), we apply another layer of optical material 350 on the original layer 34 of optical material (this layer of optical material 350 can be completed by using silicone); as shown in the fifth figure (b) A microlens mold core 3016 is pressed onto the optical material layer 350; as shown in FIG. 5(c), the microlens mold core 3016 is removed, and the microlens array structure 35 is formed on the optical material layer 350. . In addition, the microlens array structure 35 may be additionally formed in the form of a dry mold and directly attached to the first surface 301 of the substrate 30.

Please refer to the sixth figure (a) and (b), which is a schematic diagram of a second preferred embodiment of the photodiode package structure developed in order to improve the defect of the conventional photodiode package structure. It can be clearly seen from the sixth figure (a) that the photodiode package structure 4 of the present invention includes a substrate 40 having a first surface 401 and a second surface 402, a bearing space 41, and a Vias 42, 43 and an optical material layer 44, the photodiodes described in this embodiment The difference between the package structure 4 and the first preferred embodiment is that we only form the optical material layer 44 in the bearing space 41, and no additional optical material layer is formed on the optical material layer 44 to form the microlens. The array structure, that is, the microlens array structure 45 in this embodiment is integrally formed with the optical material layer 44, and the method of fabricating is as shown in FIG. 6(b), and a microlens mold core 4016 is directly pressed. The microlens array structure 45 as shown in the sixth diagram (a) can be formed on the optical material layer 44 after the microlens mold core 4016 is removed from the optical material layer 44 which has not been solidified. The technical solutions of the preferred embodiment are the same as those of the first preferred embodiment, and therefore will not be described herein.

The microlens mold cores 3016, 4016 described in the first preferred embodiment and the second preferred embodiment are mainly by a volume expansion method, a hot melt method, a surface tension or a hot extrusion method. The microlens mold cores 3016, 4016 are completed by a molding process.

In addition, in the manufacturing process steps of the above different embodiments, it can be clearly seen that the thickness of the optical material layers 34, 44 determines the formation position of the microlens array structures 35, 45, for example, in the fourth figure, The formation position of the microlens array structure 35 is located on the first surface 301 of the substrate 30, and in the sixth diagram (a), the formation position of the microlens array structure 45 is located in the bearing space 41, however The embodiment is only a preferred embodiment of the present invention. The optical material layers 34 and 44 may also be coated with a uniform thickness along the periphery of the photodiode die 300, 400. The optical material layers 34, 44 fill the load spaces 31, 41.

Referring again to the seventh (a) to (d), which are schematic diagrams of different shapes of the microlens array structures 35, 45. First preferred implementation in the above In the description of the second preferred embodiment, the plurality of microlens structures included in the microlens array structures 35 and 45 are described by taking a half-spherical three-dimensional microstructure as an example. However, the micro-invention described in the present application The microlens structure included in the lens array structure may have a semi-elliptical three-dimensional microstructure 50 of unequal lengths of two axial directions as shown in the seventh figure (a), in addition to the hemispherical three-dimensional microstructure. The semi-spherical three-dimensional microstructure 60 of the circular arc curved downward shown in the seventh figure (b), and the semi-elliptical three-dimensional micro with two circular axial lengths as shown in the seventh figure (c) Structure 70, a trihedral or tetrahedral tapered microstructure 80 as shown in the seventh diagram (d).

Based on the above various embodiments, we can clearly understand that the optical diode package structure completed by the technical means described in the present invention does solve the defects in the conventional package structure, and thus completes the development of the main purpose. The present invention has been modified by those skilled in the art, and is not intended to be protected as claimed.

The components included in the diagram of this case are listed as follows:

1‧‧‧Light emitting diode package structure

10‧‧‧Package base

11‧‧‧ lens structure

12‧‧‧ Carrying space

13‧‧‧Adhesive

100‧‧‧Lighting diode crystal grains

101‧‧‧Glossy surface

200‧‧‧Spherical lens

201‧‧‧ Polymer materials

202‧‧‧Polymer material mould

203‧‧‧Microlens array

3‧‧‧Photodiode package structure

30‧‧‧Substrate

31‧‧‧ Carrying space

32, 33‧‧‧through holes

34, 350‧‧‧ Optical material layer

35‧‧‧Microlens array structure

301‧‧‧ first surface

302‧‧‧ second surface

306‧‧‧Bevel

300‧‧‧Photodiode grains

3016‧‧‧Microlens mold

4‧‧‧Photodiode package structure

40‧‧‧Substrate

41‧‧‧ Carrying space

42, 43‧‧‧ vias

44‧‧‧Optical material layer

45‧‧‧Microlens array structure

401‧‧‧ first surface

402‧‧‧ second surface

406‧‧‧Bevel

4016‧‧‧Microlens mold

400‧‧‧Photodiode grains

50‧‧‧Half-elliptical three-dimensional microstructures with different axial lengths

60‧‧‧Curved curved downward hemispherical three-dimensional microstructure

70‧‧‧A semi-elliptical three-dimensional microstructure with two axial lengths that are curved downwards

80‧‧‧Third or tetrahedral pyramidal microstructure

The case can be further understood by the following diagrams and explanations:

The first figure is a schematic diagram of a light-emitting diode package structure having a lens structure.

The second figure (a) (b) (c) (d) (e) is a schematic diagram of the offset or tilt of the lens structure after bonding with the package base and the waste of the package base area.

The third figure (a) ~ (e), which is a flow chart of a microlens array production method Figure.

The fourth figure is a schematic diagram of a first preferred embodiment of a photodiode package structure developed to improve the conventional photodiode package structure.

The fifth diagrams (a) to (c) are schematic flowcharts of the method for fabricating the microlens array structure included in the photodiode package base structure described in the first preferred embodiment.

Fig. 6(a)(b) is a schematic view showing a second preferred embodiment of the photodiode package structure developed in order to improve the defect of the conventional photodiode package structure.

The seventh (a) to (d) are schematic views of embodiments in which the plurality of microlens structures are different in shape in the microlens array structure.

3‧‧‧Photodiode package structure

30‧‧‧Substrate

31‧‧‧ Carrying space

32, 33‧‧‧through holes

34‧‧‧Optical material layer

35‧‧‧Microlens array structure

300‧‧‧Photodiode grains

301‧‧‧ first surface

302‧‧‧ second surface

306‧‧‧Bevel

Claims (30)

An optical diode package structure is applied to a photodiode die. The package structure comprises: a substrate having a first surface; a bearing space having a top opening on the first surface of the substrate, a bottom portion for carrying the photodiode die; and an optical material layer formed in the bearing space and covering the photodiode die and having a microlens array structure, wherein the microlens array structure is located Above the photodiode grains, the light emitted by the photodiode grains and the defined light pattern are transmitted. The photodiode package structure according to claim 1, wherein the substrate is a germanium (100) lattice direction, a (110) lattice direction or a (111) lattice direction germanium semiconductor substrate. The photodiode package structure according to claim 1, wherein the substrate is a ceramic substrate of aluminum oxide or aluminum nitride material. The photodiode package structure of claim 1, wherein the substrate is a metal substrate made of an aluminum metal or a copper metal. The optical diode package structure of claim 1, wherein the bearing space is surrounded by a plurality of inclined faces, and the inclined faces are less than 90 degrees from the bottom of the carrying space. The photodiode package structure of claim 1, wherein the bearing space has a shape of a cone, a cube, a rectangle, a half ellipse or a half cone. For example, the photodiode package structure described in claim 1 of the patent scope is further included. The bottom opening has a second surface on the substrate, and the top of the via is connected to the bottom of the bearing space. The photodiode package structure of claim 1, wherein the optical material layer and the microlens array structure are optical colloids having a certain light transmittance or a thermoplastic type. The photodiode package structure according to claim 1, wherein the optical material layer is a thermocolloid or a thermoplastic optical colloid having a certain light transmittance, and the microlens array structure is A photosensitive material, a thermoset material or a thermoplastic material. The photodiode package structure of claim 1, wherein the microlens array structure is completed by pressing a mold core onto the optical material layer. The photodiode package structure according to claim 1, wherein the microlens array structure is composed of a plurality of microlens structures, and the microlens structures may be curved by a circular hemispherical three-dimensional micro A semi-elliptical three-dimensional microstructure with a structure or two axial lengths. The photodiode package structure according to claim 11, wherein the microlens structure is a circular hemispherical three-dimensional microstructure or a semi-elliptical three-dimensional microstructure with two axial lengths. . The photodiode package structure of claim 11, wherein the microlens structure is a trihedral pyramid microstructure or a tetrahedral pyramid microstructure. The photodiode package structure of claim 1, wherein the microlens array structure is located on or in the first surface of the substrate. The photodiode package structure as claimed in claim 1, wherein the photodiode die is a light emitting diode or a laser diode. An optical diode package structure is applied to a photodiode die. The package structure comprises: a substrate having a first surface; a bearing space having a top opening on the first surface of the substrate, The bottom portion is for carrying the photodiode crystal grain; an optical material layer is formed in the bearing space and covers the photodiode crystal grain; and a microlens array structure is connected to the optical material layer And being located above the photodiode of the photodiode for transmitting light emitted by the photodiode and defining a light pattern. The photodiode package structure according to claim 16, wherein the substrate is a germanium (100) lattice direction, a (110) lattice direction or a (111) lattice direction germanium semiconductor substrate. The photodiode package structure according to claim 16, wherein the substrate is a ceramic substrate of aluminum oxide or aluminum nitride material. The photodiode package structure of claim 16, wherein the substrate is a metal substrate made of an aluminum metal or a copper metal. The optical diode package structure of claim 16, wherein the bearing space is surrounded by a plurality of inclined faces, and the inclined faces are less than 90 degrees from the bottom of the carrying space. The photodiode package structure as described in claim 16 of the patent application, The shape of the bearing space is a cone shape, a positive cubic shape, a rectangular shape, a half elliptical shape or a half conical shape. The photodiode package structure of claim 16, further comprising a via hole, wherein the bottom opening is located on a second surface of the substrate, and the top of the via hole is connected to the bottom of the carrying space. The photodiode package structure of claim 16, wherein the optical material layer and the microlens array structure are optical colloids having a certain light transmittance or a thermoplastic type. The photodiode package structure of claim 16, wherein the optical material layer is a thermocolloid or a thermoplastic optical colloid having a certain light transmittance, and the microlens array structure is A photosensitive material, a thermoset material or a thermoplastic material. The photodiode package structure of claim 16, wherein the microlens array structure is formed by dry molding and attached to the first surface of the substrate and the optical material layer. The photodiode package structure of claim 16, wherein the microlens array structure is composed of a plurality of microlens structures, and the microlens structures may be curved upwards and one hemispherical three-dimensional micro A semi-elliptical three-dimensional microstructure with a structure or two axial lengths. The photodiode package structure according to claim 26, wherein the microlens structure is a circular hemispherical three-dimensional microstructure or a semi-elliptical three-dimensional microstructure with two axial lengths. . The photodiode package structure of claim 26, wherein the microlens structure is a trihedral pyramid microstructure or a tetrahedral pyramid microstructure. The photodiode package structure of claim 16, wherein the microlens array structure is located on or in the first surface of the substrate. The photodiode package structure as claimed in claim 16 is characterized in that the photodiode die is a light emitting diode or a laser diode.