TWI568117B - Package structure of laser and associated element - Google Patents

Description

Laser package structure and related components

This invention relates to a package structure, and more particularly to a laser package structure and related components.

Please refer to FIG. 1A , which is a schematic diagram of a package structure of a conventional edge-emitting laser diode. The package structure 100 includes a laser diode 104 that is attached to a primary submount 102. Furthermore, the secondary adhesive substrate 102 is fixed on the circuit board 106 (such as a printed circuit board, PCB), and has at least two layout traces on the circuit board 106 as two electrodes (not shown), and The electrodes are electrically connected to the laser diode 104. Basically, the manner of electrical connection can be accomplished in a variety of known ways, such as wire bonds and the like. Moreover, after the two electrodes provide a bias voltage, the laser diode 108 can generate the laser beam 108.

Please refer to FIG. 1B , which is a schematic diagram of a laser of a conventional transistor outline CAN (TO CAN) package.

A circular metal base 130 has a projection 130a and a metal cap 122 overlies the circular metal base 130 and forms a TO CAN package. In the space 126 covered by the metal casing 122 and the circular metal base 130, a laser diode 132 is attached to the sub-mount 134, and the sub-adhesive substrate 134 is fixed to the circular metal base 130. Projection portion 130a. Furthermore, two electrodes 150 extend into the space 126 covered by the metal casing 122 and the circular metal base 130, and are electrically connected to the laser diode 132. Furthermore, Yu Er After the electrodes 150 provide a bias voltage, the laser diode 132 can output the laser beam 120 from the window 124. Obviously, with the TO CAN package structure, the edge-emitting laser diode 132 can be packaged into a surface-emitting laser.

As is well known, the TO CAN package structure is too bulky and is not suitable for use in small electronic devices such as cell phones. Therefore, other types of package structures have gradually been developed.

Please refer to FIG. 2A, which is a schematic diagram of a conventional laser beam steering package structure. This technology is disclosed in US 2009/0047024. In this technique, package structure 200 acts as a transmit side in an optical transceiver module that couples output laser beam 233 to a fiber.

The package structure 200 includes a laser diode 210, an optical system 230, a photodetector 220, a reflective element 250, a substrate 270, and a controller 260. Basically, the laser diode 210 emits an output light beam from a front facet and a monitoring light beam from a rear facet. The output laser beam is coupled into fiber 270 via optical system 230, reflective element 250.

The monitoring beam is absorbed by the photodetector 220 and correspondingly generates a photoelectric signal to the controller 260, and the controller 260 generates a feedback signal to the laser diode 210 for controlling the laser diode according to the photoelectric signal. The intensity of the output laser beam of 210 is (intensity).

Please refer to FIG. 2B to FIG. 2D , which are schematic diagrams showing the fabrication of conventional reflective elements. As shown in FIG. 2B, a wafer 280 is polished and a metal layer 290 is formed on the polishing surface 281 to form a mirroring surface 286.

Further, as shown in FIG. 2C, a diced surface 284 is formed after the wafer wafer 280 is cut at positions 282 and 283 by a 45 degree bevel blade. Furthermore, a regular dicing blade is used to cut straight at position 285 and form a separate separation at positions 287 and 288. A plurality of reflective elements 250.

After flipping one of the reflective elements of FIG. 2C by 135 degrees, it is the reflective element 250 as shown in FIG. 2D. In addition, the cutting surface 284 is fixed to the substrate 270, and the reflecting surface 286 can reflect and steer the output laser beam.

The main object of the present invention is to provide a laser package structure and related components. The present invention designs a new reflective element to reflect and steer the output laser beam of the edge-emitting laser diode to form a surface-emitting laser. Furthermore, the process of the reflective element is modified to have both optical elements for reflection and light detection, and the volume of the package structure is effectively reduced.

The invention relates to a laser package structure, comprising: a heat dissipation base; a laser element fixed to a surface of the heat dissipation base to emit a first laser beam; and a first optical component Having a reflective surface such that a first portion of the first laser beam can be penetrated and a second portion of the first laser beam is reflected; wherein an etch process is utilized for the first optical Forming a wafer surface on the element and processing the wafer surface to become the reflection surface; or forming a first slope on the first optical element by using a cutting process, and processing the first slope to become the reflection surface.

The present invention relates to an optical component in a package structure, comprising: a substrate having a slope, a first surface and a second surface, and an angle between the slope and the second surface; a doped layer Between the first surface and the slope; a dielectric layer covering the slope; and an electrode contacting the doped layer; wherein the dielectric layer can be covered by a first portion of a laser beam Penetrating and reflecting a second portion of the laser beam such that the optical element produces an induced photocurrent based on the first portion of the laser beam.

In order to better understand the above and other aspects of the present invention, the preferred embodiments are described below, and in conjunction with the drawings, the detailed description is as follows:

100‧‧‧Package structure

102‧‧‧ times adhesion substrate

104‧‧‧Laser diode

106‧‧‧Circuit board

108, 120‧‧‧Laser beam

122‧‧‧Metal housing

124‧‧‧Window

126‧‧‧ Space

130‧‧‧round metal base

130a‧‧‧Protruding

132‧‧‧Laser diode

134‧‧‧adhesive substrates

150‧‧‧electrode

200‧‧‧Package structure

210‧‧‧Laser diode

220‧‧‧Photodetector

230‧‧‧Optical system

233‧‧‧ Output laser beam

250‧‧‧reflecting elements

260‧‧‧ Controller

270‧‧‧Substrate

280‧‧‧矽 wafer

281‧‧‧ Polished surface

282, 283, 285, 287, 288‧‧‧ positions

284‧‧‧ cutting surface

286‧‧ ‧ mirror

290‧‧‧metal layer

310, 610‧‧‧矽 substrate

312, 314, 316‧‧ position

320‧‧‧ Cover layer

331‧‧‧crystal face

332, 334, 336, 338‧‧‧ optical components

402, 502, 702‧‧ ‧ laser diode

404, 504, 704‧‧‧ times adhesion substrates

410, 550, 570, 710‧‧‧ circuit boards

420, 560, 572, 720‧‧‧ output laser beam

422, 574‧‧‧Monitor laser beam

500‧‧‧Optical components

520‧‧‧Doped layer

525‧‧‧electrode

530, 652‧‧‧reflective layer

562‧‧‧Part II

564‧‧‧Part 1

612, 614, 616‧‧‧ position

632, 634, 636, 638‧‧‧ optical components

650‧‧‧ Bevel

651‧‧‧SiO ₂ layer

FIG. 1A is a schematic diagram showing a package structure of a conventional edge-emitting type laser diode.

FIG. 1B is a schematic view showing a surface-emitting type laser of a conventional transistor appearance cylindrical package.

FIG. 2A is a schematic view showing a conventional laser beam steering package structure.

2B to 2D are schematic views showing the fabrication of a conventional reflective element.

3A to 3C are diagrams showing the fabrication of the optical component of the present invention.

FIG. 4 is a view showing a first embodiment of the package structure of the present invention.

Figure 5A illustrates another optical component of the present invention.

FIG. 5B illustrates a second embodiment of the package structure of the present invention.

FIG. 5C illustrates a third embodiment of the package structure of the present invention.

FIG. 5D illustrates a fourth embodiment of the package structure of the present invention.

6A to 6C are schematic views showing the fabrication of still another reflective element of the present invention.

Figure 7 is a diagram showing a fifth embodiment of the package structure of the present invention.

According to an embodiment of the present invention, the optical element of the present invention is etched on a ruthenium substrate to form a habit plane, and the wafer face is processed to form a reflective surface of the optical element, and the optical element can be used as A reflective element. Please refer to FIG. 3A to FIG. 3C , which are schematic diagrams showing the fabrication of the optical component of the present invention.

First, a mask layer 320 having an opening, such as a SiO ₂ layer, is formed on the first surface (upper surface) of the substrate 310. Next, after etching the tantalum substrate 310 with a chemical etching solution, two trenches of the third drawing can be formed. As shown in Figure 3A, a particular chemical etchant is selected to be etched on a wafer of a particular crystal orientation. When the opening of the mask layer 320 is small, a V-shaped groove is formed, and the two side walls of the groove are the (111) plane, that is, the wafer surface. In addition, when the opening of the mask layer 320 is large, a (100) plane is formed at the bottom of the trench, and the two sidewalls of the trench are (111) planes. The angle between the crystal face and the (100) face is 54.7 degrees. In other words, the present invention selects the ruthenium substrate 310 whose first surface is the (100) plane, that is, the angle between the first surface of the ruthenium substrate 310 and the wafer surface is controlled to be 54.7 degrees.

To adjust the angle of the reflecting surface to 45 degrees. As shown in FIG. 3B, when the ingot was cut into a tantalum substrate, the cutting angle was 9.7 degrees with respect to the (100) plane of the tantalum substrate. Thereafter, as shown in FIG. 3C, the plurality of optical elements 332, 334, 336, 338 are separated after being removed from the mask layer 320 and directly cut the substrate 310 at positions 312, 314, and 316. Of course, the above cutting angle can be cut according to the actual required angle, and is not limited to 9.7 degrees.

In Fig. 3C, the wafer faces 331 and 335 of the optical elements 332 and 336 exhibit an angle of 45 degrees with the bottom cut surface, which is suitable for use in the package structure of the face-illuminated laser of the present invention. The following package structure is described by the optical element 332. Of course, the optical element 336 may be used instead, and details are not described herein again.

Please refer to FIG. 4, which illustrates a first embodiment of the package structure of the present invention. The package structure includes a circuit board 410, a laser diode 402, a primary adhesion substrate 404, and an optical component 332. The laser diode 402 is fixed to the sub-adhesive substrate 404. Furthermore, the secondary adhesive substrate 404 and the optical component 332 are fixed to a surface of the circuit board 410. Furthermore, the laser diode 402 forms a laser element with the sub-adhesive substrate 404, and the circuit board 410 is a heat sink.

As shown in FIG. 4, in this package structure, the laser diode 402 emits an output laser beam 420 from the front surface and directly illuminates the wafer face 331 of the optical element 332. The output laser beam is reflected by the wafer face 331 (reflecting surface) of the optical element 332 to change the path of the output laser beam. In other words, most of the output laser beam can be reflected by the reflecting surface, and a small portion of the output laser beam passes through the reflecting surface. Therefore, the beam steering package structure of the edge-emitting type laser diode of the present invention is completed. Of course, in the final process, silicone (not shown) may be filled on the circuit board 410 to cover all components to protect all components on the circuit board 410.

Furthermore, technicians in this field can further process the crystal Knead the surface to form a reflective layer with better reflectivity. For example, a metal layer (for example, silver) or a dielectric high-reflection film layer is plated on the wafer face 331.

In addition, a person skilled in the art can directly fix the laser diode 402 and the optical element 322 to the sub-adhesive substrate 404, and then fix the sub-adhesive substrate 404 to the surface of the circuit board 410. Alternatively, on the surface of the circuit board 410, the other side of the laser diode 402 is fixed with a photodetector (not shown) for receiving the monitoring laser beam emitted from the rear surface of the laser diode 402 (monitoring light). Beam).

Furthermore, the optical element of the above 3Cth diagram can be further processed into an optical element having a specific function. Please refer to FIG. 5A, which is a schematic diagram of another optical component of the present invention. In addition, FIG. 5B is a second embodiment of the package structure of the present invention. Basically, the following optical element 500 is formed by processing the optical element 336 of FIG. 3C. Of course, it can also be replaced by optical element 332, and will not be described again.

As shown in FIG. 5A, a doping process is performed on the slope and the upper surface of the germanium substrate 310 to form a doped layer 520 and a PN junction. For example, if the germanium substrate is a P-type substrate, an N-type doping process is performed to form an N-type doped layer, and a P-type substrate and an N-type doped layer are at a PN junction. In addition, a dielectric layer 530 is formed over the doped layer 520, that is, the dielectric layer 530 is covered on the slope of the germanium substrate 310, and then an electrode 525 is formed in contact with the doped layer 520.

Basically, the dielectric layer 530 can form a dielectric layer 530 of a specific reflectivity according to actual needs. For example, 95% reflectivity, 5% transmittance of dielectric layer 530. Therefore, the laser beam penetrating through the dielectric layer 530 enters the PN junction, that is, the induced photocurrent is generated by the photoelectric effect. In other words, the optical component 500 disclosed in FIG. 5A is a reflection and detection integration component having a reflection function and a light detection function.

Of course, in addition to designing the dielectric layer 530 having high reflectivity and low transmittance, the dielectric layer 530 having low reflectivity and high transmittance can also be designed. The optical component 500 designed under this condition, since most of the laser beam penetrates to The PN junction, a small portion of the laser beam is reflected, so it can be used as the optical component 500 of the light-detecting side function.

Please refer to FIG. 5B, which illustrates a second embodiment of the package structure of the present invention. The package structure includes a circuit board 550, a laser diode 502, a primary adhesion substrate 504, and an optical component 500. The laser diode 502 is fixed to the sub-adhesive substrate 504. Furthermore, the secondary adhesive substrate 504 and the optical component 500 are fixed to the surface of the circuit board 550. Furthermore, the laser diode 502 and the secondary adhesive substrate 504 form a laser element, and the circuit board 550 is a heat dissipation base, and the optical component 500 is a reflection and detection integration component.

As shown in FIG. 5B, in this package structure, the laser diode 502 emits an output laser beam 560 from the front surface. The output laser beam 560, via the dielectric layer 530 of the optical component 500, directs the first portion 564 of the output laser beam into the PN junction for generating an induced photocurrent. Additionally, a second portion 562 of the output laser beam is output that changes the path of the output laser beam via reflection. Therefore, the package structure of the present invention is completed. Of course, in the final process, a silicone (not shown) may be filled on the circuit board 550 to cover all components to protect all components on the circuit board 550.

Similarly, a person skilled in the art can directly fix the laser diode 502 and the optical element 500 to the sub-adhesive substrate 504, and then fix the sub-adhesive substrate 504 to the surface of the circuit board 550.

Please refer to FIG. 5C, which illustrates a third embodiment of the package structure of the present invention. The package structure includes a circuit board 570, a laser diode 502, a primary adhesion substrate 504, and an optical component 500. The laser diode 502 is fixed to the sub-adhesive substrate 504. Furthermore, the secondary adhesive substrate 504 and the optical component 500 are fixed to the surface of the circuit board 570. Furthermore, the laser diode 502 and the sub-adhesive substrate 504 form a laser element, and the circuit board 570 is a heat dissipation base, and the optical element 500 is an optical element 500 of a light-detecting side function.

As shown in FIG. 5C, in this package structure, the laser diode 502 emits an output laser beam 572 from the front surface and monitors the laser beam from the rear surface output. 574. Thus, the monitoring laser beam 574 passes through the dielectric layer 530 of the optical component 500, penetrating most of the monitored laser beam 574 into the PN junction for generating an induced photocurrent. In addition, monitoring the small two parts of the laser beam (not shown) is reflected. Therefore, the package structure of the present invention is completed. Of course, in the final process, silicone (not shown) may be filled on the circuit board 570 to cover all components to protect all components on the circuit board 570.

Please refer to FIG. 5D, which illustrates a fourth embodiment of the package structure of the present invention. The package structure includes a circuit board 410, a laser diode 402, a primary adhesion substrate 404, a first optical component 332, and a second optical component 500. The laser diode 402 is fixed to the sub-adhesive substrate 404. Furthermore, the secondary adhesive substrate 404 and the first optical component 332 are fixed to a surface of the circuit board 410. Furthermore, the laser diode 402 forms a laser element with the sub-adhesive substrate 404, and the circuit board 410 is a heat dissipation base, the first optical element 332 serves as a reflective element, and the second optical element 500 is provided with a light detector. Side-functioning optical components.

As shown in FIG. 5C, in this package structure, the laser diode 402 emits an output laser beam 420 from the front surface and a laser beam 422 from the rear surface. The output laser beam is reflected by the wafer face 331 (reflecting surface) of the first optical element 332 to change the path of most of the output laser beam. Furthermore, the monitoring of the laser beam 422 via the dielectric layer 530 of the second optical component 500 causes a majority of the monitored laser beam 422 to enter the PN junction for generating the induced photocurrent and a small portion of the monitored laser beam ( Not shown) the path of the monitored laser beam is monitored via reflection.

Of course, in the final process, silicone (not shown) may be filled on the circuit board 410 to cover all components to protect all components on the circuit board 410.

Furthermore, those skilled in the art can further process the wafer surface to form a reflective layer having a better reflectance. For example, a metal layer (for example, silver) or a dielectric high-reflection film layer is plated on the wafer face 331.

In addition, a person skilled in the art can directly fix the laser diode 402, the second optical component 500 and the first optical component 322 to the sub-adhesive substrate 404, and then fix the sub-adhesive substrate 404 to the surface of the circuit board 410. .

Further, the optical element of the present invention may be formed by directly cutting a bevel on a tantalum substrate and treating the bevel to form a reflecting surface of the optical element. Please refer to FIG. 6A to FIG. 6C , which are schematic diagrams showing the fabrication of still another optical component of the present invention.

First, on the first surface (upper surface) of the substrate 610, the ruthenium substrate 610 is cut with a 45 degree bevel blade and a V-shaped groove is formed. Furthermore, the angle between the two sidewalls of the trench and the second surface (lower surface) of the germanium substrate 610 is 45 degrees.

As shown in FIG. 6B, a plurality of separate optical elements 632, 634, 636, 638 are formed after the substrate 610 is cut straight at positions 612, 614, and 616. Of course, the cutting angle of the bevel blade described above can be cut according to the actual required angle, and is not limited to 45 degrees.

Moreover, the slope of the optical elements 632, 634, 636, 638 and the second surface of the substrate exhibit an angle of 45 degrees, which is suitable for forming a reflective surface after processing, and is applied to the package structure of the surface-emitting laser of the present invention.

Hereinafter, the optical element 630 will be taken as an example for continued description. As shown in Fig. 6C, the slanted surface 650 after cutting is rough. Therefore, a flattening process needs to be performed first. In the planarization process, a liquid SiO ₂ layer is formed on the slope 650 by a spin on glass (SOG) process (or other polymer material). Thereafter, the flatness of the slope 650 can be increased after the SiO ₂ layer 651 after curing. Next, a reflective layer 652 is formed on the SiO ₂ layer 651, and the material thereof may be metal (for example, silver) or a dielectric material.

Of course, the planarization process may be replaced by etching, and the bevel 650 may be planarized by etching the slope 650 with an etchant. After that, a reflective layer can be formed.

Please refer to FIG. 7, which illustrates a fifth embodiment of the package structure of the present invention. The package structure includes a circuit board 710, a laser diode 702, a primary adhesion substrate 704, and an optical component 632. The laser diode 702 is fixed to the sub-adhesive substrate 704. Furthermore, the secondary adhesive substrate 704 and the optical component 632 are fixed. It is fixed on the surface of the circuit board 710. Furthermore, the circuit board 710 is a heat sink base.

As shown in FIG. 7, in this package structure, the laser diode 702 emits an output laser beam 720 from the front surface. The output laser beam changes the path of the output laser beam via the reflective layer 652 of the optical element 732. Therefore, the package structure of the surface-emitting laser of the present invention is completed. Of course, in the final process, silicone (not shown) may be filled on the circuit board 710 to protect all components on the circuit board 710.

Furthermore, those skilled in the art can directly fix the laser diode 702 and the optical element 632 to the sub-adhesive substrate 704, and then fix the sub-adhesive substrate 704 to the surface of the circuit board 710. Alternatively, on the other side of the laser diode 702 on the surface of the circuit board 710, a photodetector (not shown) is fixed for receiving the monitoring laser beam emitted from the rear surface of the laser diode 702 (monitoring light) Beam).

As apparent from the above description, an advantage of the present invention is to provide a beam steering package structure and related components of an edge-emitting type laser diode. The edge-emitting laser diode and the optical component are packaged, and have the advantage of small size, and can be applied to small electronic devices (such as mobile phones).

In conclusion, the present invention has been disclosed in the above preferred embodiments, and is not intended to limit the present invention. A person skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, the scope of the invention is defined by the scope of the appended claims.

331‧‧‧crystal face

332‧‧‧Optical components

402‧‧‧Laser diode

404‧‧‧adhesive substrates

410‧‧‧Circuit board

420‧‧‧ Output laser beam

Claims (11)

A laser package structure includes: a heat dissipation base; a laser element fixed to a surface of the heat dissipation base to emit a first laser beam; and a first optical element having a reflective surface Having a first portion of the first laser beam penetrated and a second portion of the first laser beam reflected; wherein an etch process is used to form a crystal on the first optical element The surface of the wafer is processed to form the reflective surface; or a first bevel is formed on the first optical element by a cutting process, and the first bevel is processed to become the reflective surface. The package structure according to claim 1, wherein the heat dissipation base is a circuit board, and the laser element comprises a laser diode and a primary adhesion substrate, and the laser diode is fixed to the adhesion layer. a substrate, and the adhesive substrate is fixed to the circuit board. The package structure of claim 1, wherein a reflective layer is formed on the crystal face or the first slope as the reflective surface. The package structure of claim 1, wherein the first optical component comprises: a substrate having the reflective surface, a first surface and a second surface, the second surface being fixed to the heat dissipation base. And the second surface is cut to control an angle between the second surface and a (100) plane. The package structure of claim 4, wherein the first optical component further comprises: a doped layer under the first surface of the substrate and the reflective surface; a dielectric layer covering the crystal a face or the first slope; and an electric a first portion of the first laser beam passing through the dielectric layer for generating an induced photocurrent; and the second portion of the first laser beam is The dielectric layer is reflected. The package structure of claim 1, wherein the first optical component comprises: a substrate having the slope, a first surface and a second surface, and the slope is formed by the cutting process, To control an angle between the second surface and the slope. The package structure of claim 6, wherein the slope is formed by a planarization process, and then a reflective layer is formed on the slope, wherein the planarization process is a spin coating process or an etching process. Process. The package structure of claim 1, further comprising: a second substrate comprising: a substrate having a second slope, a first surface and a second surface, and the second slope and the second An angle between the surfaces; a doped layer under the first surface and the second bevel; a dielectric layer covering the second bevel; and an electrode contacting the doped layer; wherein The laser element can output a second laser beam, and the dielectric layer can be penetrated by a first portion of the second laser beam, and the second optical element correspondingly generates an induced photocurrent. An optical component in a package structure, comprising: a substrate having a slope, a first surface and a second surface, and an angle between the slope and the second surface; a doped layer located at the first a surface and a lower surface of the slope; a dielectric layer covering the slope; and an electrode contacting the doped layer; Wherein the dielectric layer is penetrated by a first portion of a laser beam and reflects a second portion of the laser beam such that the optical element produces an inductive light based on the first portion of the laser beam Current. The package structure of claim 9, wherein an etching process is used to form a wafer surface on the optical element and become the slope. The package structure of claim 9, wherein the bevel is formed on the optical element by a cutting process.