TW589772B - Method for coating laser diode facet - Google Patents

Abstract

A method for coating laser diode facet comprising the following steps: inserting a spacer between adjacent laser-diode chips, wherein each laser-diode chip has a first electrode surface, a second electrode surface, a first resonance facet covering on a waveguide wire, a second resonance facet, and a length of the resonance, and the spacer has a first surface and a second surface, the first surface having trench crisscrossed with the waveguide wire on both ends to expose partial the waveguide wire, and the first surface of the spacer coupling to the first electrode surface of the laser-diode chip, the second surface coupling to the second electrode surface of the laser-diode chip; coating upon the first resonance facet of the laser-diode chip; and then coating upon the second resonance facet of the laser-diode chip.

Description

0) 589772 Description of the invention The technical field to which the invention belongs The present invention relates to a method of laser diode resonance related to the phenomenon of uneven coating of the mirror surface by changing the spacer rod or the laser two-vibration mirror. The technical field of Fa Heng, Sakisaki, Saki, and real money-type reliance instructions) Mirror coating method, especially the shape of the core wafer to avoid common

The thin film can protect the laser diode's resonance 材 ... or other materials, and can change the reflection of the resonant mirror: surface: insensitive during operation. As shown in Fig. 1a, the diode wafer 10, which is known from the resonance mirror edge Asada field-polar body, is arranged in order. The electrode surface 12 is close to the exposed mirror surface "a, and the outermost crystals 14b 'are plated on the first-so that the film is plated on the laser diode wafer spacer or cooler to protect the' mirror Ua, and then inverted To the second resonance mirror = I plane 12. The first total coating is plated. Think l4b, and complete the second mirror i. Because the width of the laser diode wafer is about 100 micrometers, it is small and light, between 100 micrometers, and uneven when the thickness of the column is about, between the raised crystal wafers The frictional force caused by the mirror surface unevenness affects the laser diode to shield adjacent wafers. During the coating process, as shown in Figure 1b, it can be arranged in a special shape. At this point, when a wide-angle small-diode wafer 10 is placed between 10 diode wafers of the conventional technique, the lightning spacer 16 is used to separate the adjacent J and laser diode resonances. In terms of cavity length, the first-resonance mirror surface 14a will not shoot two polar wafers 10 in such a way that they shield each other, but the second '6-589772

The resonance mirror surface 14b and the spacer rod 16 are arranged on the same plane, and there may still be unevenness, and they must be rearranged.

U.S. Patent No. 6 1 2 5 5 3 0 is a tool for rolling and neatly arranging wafers. This tool is easy to cause damage or pollution to the resonance surface after rolling the resonance mirror surface of the laser diode wafer. U.S. Patent Nos. 5,9 1 1,8 3 0 and 6,0 2 6,5 5 7 respectively disclose the use of a clamp for holding a laser diode wafer during mirror plating, and simultaneously Spacer rods with a width smaller than the cavity length of the diode laser wafer are placed between the polar body wafers. All the patents mentioned above need to make precise and complicated jigs. The size of the jigs is not only huge, but also occupies the coating space, thus reducing the production capacity of laser diode mirror coating. SUMMARY OF THE INVENTION In view of the many shortcomings of conventional laser diode mirror coating in the above background of the invention, the present invention provides a method of laser diode mirror coating to overcome the problems derived from conventional techniques.

The invention is mainly used for laser diode resonance mirror coating. By changing the shape of the spacer rod or the laser diode wafer, the coating can be prevented from being uneven, and it is not necessary to use a sophisticated and bulky fixture, which can save Cost of production. In addition, the present invention further discloses a method for manufacturing a grooved laser diode wafer and a spacer rod. According to the above-mentioned purpose, the present invention provides a method for coating a laser diode wafer with a resonant mirror surface. The step is to use a spacer rod to separate adjacent laser diode wafers, wherein the laser diodes The wafer has a first electrode surface, a second electrode surface, a first resonance mirror surface, and a second resonance mirror (2)

The solid and straight description of the surface is shown in Figure 2. At the time of the sheet 2 4, the mirror mirror is at least the length of the cavity and the first electrode surface covers a waveguide line. The gate rod has a first table surface and a second table surface. A mesa is provided with a groove at both ends of the vertical direction of the waveguide line, and the first mesa of the spacer rod is attached to the first electrode face of the J 锫 emitter wafer, and the second mesa is attached to the second of the laser diode wafer. Electrode surface. The film is coated on the first resonance mirror surface of the laser diode wafer, and the film is coated on the second resonance mirror surface. Embodiments Some embodiments of the present invention will be described in detail as follows. However, in addition to the detailed description, the present invention can be widely implemented in other embodiments, and the scope of the invention should not be limited to what is claimed in the patent scope. FIG. 2 is a first preferred embodiment of the present invention. The width of the spacer rod 20 is equal to the length of the resonant cavity 25 of the laser diode wafer 25, and the thickness 22 and the length of the laser diode 25 are longer than the laser. Diode wafer 25. The spacer rod 20 has a mouth surface and a first table surface 23b, and grooves are formed at both ends of the first table surface 23a. Thus, the spacer rod 20 has two table surfaces of different widths. Mirror coating arrangement 'Neighboring laser I. pi Du sister wafers 25 are placed with spacer rods 20, and the mouth surface 23a of the spacer rod is attached to the laser diode wafer 25 with the first pole surface 29a of the waveguide 28' The second mesa 2 of the spacer rod is attached to the second electrode surface of the laser diode wafer, so that the groove 2 4 of the spacer rod faces the end of the waveguide line 2 8 to avoid high prices, especially Diode resonance mirror is blocked. The depth 26 and width 27 of the above-mentioned spacer rod groove 24 are both greater than 5 micrometers, and the preferred groove depth is between ~ 20 micrometers, and the groove width is between 30 and 0 micrometers. The thickness is greater than Na *, but the thickness of a polar wafer that does not come out of the field is 100 microns, and the preferred thickness is with laser (3)

Diode wafers are the same thickness. The material of the spacer bar 20 may be a semiconductor wafer, a metal, a Teflon, a plastic, and other easily processed materials. If a semiconductor wafer is used as the material for the spacer rod, the steps shown in Figs. 3a to 3c are not used. A photoresist layer 32 is formed on the semiconductor wafer substrate 30, and then a patterned photomask 34 is used to define the trench positions, and then a trench etching step is performed to finally remove the photomask 34 and photoresist layer 32. The width of the trench 36 is greater than 10 microns, and the depth 37 is greater than 5 microns. After the trench etching is completed, the wafer 30 is ground to a thickness similar to that of the laser diode, and split or cut along the center line 38 of the trench to complete the production of the spacer rod 39. FIG. 4 is a second preferred embodiment of the present invention. The width 4 of the spacer rod 40 is equal to the length of the laser diode resonator cavity. The thickness 42 is equivalent to the laser diode wafer, and the length is longer than the laser diode. Body wafer. The four corners of the cross section of the spacer have grooves 4 4. The depth 4 6 and width 4 7 of the spacer groove 4 4 are larger than 5 micrometers, and the preferred groove depth 4 6 is between 10 and 20 micrometers, and the groove width 4 7 is between 30 and 50. Between micrometers. The thickness of the spacer rod 40 is greater than 70 microns, but does not exceed the thickness of the laser diode wafer by 100 microns. The preferred thickness is the same as the thickness of the laser diode wafer. When the mirror is arranged, the spacer rod 40 is placed between the adjacent laser diode wafers 45. The groove 44 of the spacer rod faces the mirror end of the laser diode waveguide 4 8 and the laser diode resonates. The mirror will not be hidden. The material of the spacer rods can be easily processed materials such as semiconductor wafers, metals, Teflon, and plastics. If a semiconductor wafer is used as the material for manufacturing the spacer rod 40, it can be manufactured as shown in Figs. 5a to 5e. A photoresist 51 is coated on the semiconductor wafer 50, aligned with a first photomask 52 having a groove pattern, exposed and exposed 589772

(4) Develop and make the first groove 5 5 a by etching. The spacing between the grooves 5 5 a is equal to the width of the laser z-pole body. The width 56 of the grooves must be greater than i 0 μm, and the depth 57f is greater than 5 μm. After the first side trench 55a is etched, the photoresist is removed and the wafer is ground to a thickness similar to that of the laser diode. A honeycomb photoresist 5 3 ′ is placed on the second side of the wafer and a second photomask 5 is used. 4 Align the grooves 5 5 b on the first side, expose and develop on the first side, and make the second side groove 55 b by etching. After the second side trench 55b is etched, the photoresist 53 is removed, and splitting or cutting is performed along the center line 59 of the trench to complete the fabrication of the spacer 40. Figures 6a, 6b and 6c show a third preferred embodiment of the present invention. As shown in Figure 6 & 6b, the width of the spacer rods with different shapes can be smaller than the length of the cavity of the laser diode wafer. However, to avoid mirror coating, the electrodes are covered by a thin film. The length difference of the cavity of the laser diode wafer should not be too large. Or as shown in FIG. 6c, the width 62 of the spacer rod 60 is smaller than the length 63 of the laser diode resonator cavity, and only the first end surface 66a of the spacer rod 60 has a groove 64 and the second end surface 661) No grooves. When the mirror coating is arranged, a spacer rod 60 is placed between adjacent laser diode wafers 6 and 6. The groove 6 4 of the spacer rod 60 is attached to the laser diode wafer 6 丨 with the electrode surface 6 8 of the waveguide wire 6 7 so that the groove 64 of the spacer rod 60 faces the mirror surface of the laser diode waveguide 67 The two resonant mirror surfaces 6 5 a and 6 5 b of the end-end laser diode wafer will not be shielded. Figures 7a to 7c are used to illustrate the fabrication of a laser diode wafer with a trench structure. After the laser diode wafer 70 has completed the wafer process on the first side, the second surface is ground and the electrode 71 is plated, and then the laser diode wafer 70 is coated with a photoresist 7 2 on the second side. The groove pattern of the photomask 7 3 is exposed and developed, and then -10- 589772

(5) Trenches 7 8 are made by etching. The spacing between the trenches 7 8 is equal to the length of the cavity of the laser diode wafer. The width 74 of the trench must be greater than 10 microns, and the depth 75 must be greater than 5 microns. After the trench etching is completed, the photoresist 72 is removed, and finally split along the center line 7 6 of the trench. FIG. 8 is a fourth preferred embodiment of the present invention. When the mirror coating is arranged, the first electrode surface and the second electrode surface of the adjacent laser diode wafer 80 are aligned and attached, and the laser diode wafer is aligned. The groove 82 of 80 faces the adjacent laser diode waveguide 8 4 so that the laser diode resonant mirror will not be shielded.

〇 According to the above, by changing the shape of the spacer rod or the laser diode wafer, the present invention can avoid the occurrence of non-uniform coating and does not require the use of precise and complicated jigs, which can save production costs. In addition, the present invention also discloses a method for manufacturing a laser diode wafer with a groove and a spacer rod.

The above are only preferred embodiments of the present invention, and are not intended to limit the scope of patent application for the present invention; all other equivalent changes or modifications made without departing from the concepts disclosed by the present invention should be included in the following applications Within the scope of the patent. Brief description of the drawings Figures 1a and 1b show the conventional method of laser diode resonant mirror key film. FIG. 2 is a first preferred embodiment of the present invention. 3a to 3c are used to explain the method for manufacturing the spacer rod shown in FIG. FIG. 4 is a second preferred embodiment of the present invention. 5a to 5e are used to explain the method for manufacturing the spacer rod shown in FIG. 6a to 6c show a third preferred embodiment of the present invention. 589772

(6) Figures 7a to 7c are used to illustrate the production of a tool. FIG. 8 is a representative symbol of the main part of the fourth preferred embodiment of the present invention. 10 Laser diode wafer 12 Electrode surface 1 4 Resonant mirror surface 16 Spacer 2 0 Spacer 2 1 Spacer width 2 2 Spacer thickness 23a 1 mesa 2 3 b second mesa 2 4 groove 2 5 laser diode wafer 26 groove depth 27 groove width 2 8 wave conductor 29a first electrode surface 2 9 b second electrode surface 30 substrate 3 2 light Resistor 34 photomask 3 6 trench width laser structure with trench structure. 3 7 groove depth 3 8 groove center line 3 9 spacer rod 4 0 spacer rod 4 1 spacer rod width 42 spacer rod thickness 44 groove 4 5 laser diode wafer 46 groove depth 47 groove width 4 8 Wave conductor 50 substrate_ 5 1 photoresist 52 first photomask 5 3 photoresist 54 second photomask 55 groove 5 6 groove width 5 7 groove depth 5 9 groove centerline -12- 589772 ⑺

60 Spacer rod 62 6 1 Laser diode wafer 63 Laser diode wafer cavity length 65 Resonant mirror surface 73 66a Spacer rod first — end surface 74 66b Spacer rod second end surface 75 67 Wave conductor 76 68 Electrode surface 78 70 Lightning Laser Diode Wafer 80 7 1 Electrode 82 72 Photoresistor 84 Spacer Bar Width Mask Groove Width Groove Depth Groove Center Line Groove φ Laser Diode Wafer Waveguide Line

Claims (1)

589772 Patent application scope 1. A method for coating a laser diode with a resonant mirror surface, comprising the following steps: using a spacer rod to separate adjacent laser diode wafers, wherein the laser diode wafers Having a first electrode surface, a second electrode surface, a first resonance mirror surface, a second resonance mirror surface, and a cavity length, and the first electrode surface covers a waveguide line of the laser diode wafer, The spacer has a first mesa and a second mesa, wherein the first mesa and the two ends of the laser diode wafer perpendicular to the waveguide line each have a groove, and the first mesa is attached to the mine. The first electrode surface of the emitting diode wafer, the second mesa surface of the spacer rod is attached to the second electrode surface of the laser diode wafer; coating on the first resonant mirror surface; and coating on the second resonance On the mirror. 2. The method for coating a laser diode resonance mirror as described in item 1 of the scope of the patent application, wherein the width of the spacer rod is between the length of the resonant cavity and 50 μm less than the length of the resonant cavity. 3. The method for coating the laser diode resonant mirror surface as described in item 1 of the scope of the patent application, wherein when the above-mentioned spacer rod is inserted into two adjacent laser diode wafers, the first surface of the spacer rod Neither the second mesa nor the first mesa exceeds the first and second resonant mirrors of the laser diode wafer. 4. The method of laser diode resonance mirror coating as described in item 1 of the scope of the patent application, wherein the thickness of the above-mentioned spacer rod is between 7 and 0. 589772 micrometers and 100 micrometers more than the thickness of the laser diode wafer. 5. The method for coating a laser diode resonance mirror as described in item 1 of the scope of the patent application, wherein the thickness of the spacer rod is equal to the thickness of the laser diode wafer. 6. The method for coating the laser diode resonance mirror as described in item 1 of the scope of the patent application, wherein the above-mentioned spacer rod is one selected from the group consisting of semiconductor wafer, metal, Teflon, and plastic. material. φ 7. The method for coating the laser diode resonance mirror surface as described in item 1 of the scope of the patent application, wherein the first mesa and the two ends in the vertical direction of the waveguide line each include a groove. 8. The method for coating the laser diode resonant mirror surface as described in item 7 of the scope of the patent application, wherein the depth of the groove from the first stage is at least 5 microns, and the preferred depth is between 10 and 2 Between 0 microns. 9. The method for coating a laser diode wafer with a resonant mirror as described in item 7 of the scope of the patent application, wherein the width of the first mesa is at least less than φ and the length of the resonant cavity is 10 micrometers, and the preferred width is less than The cavity length is between 60 and 100 microns. 1 0. A method for coating a laser diode with a resonant mirror surface, comprising the following steps: arranging a plurality of laser diode wafers, wherein the laser diode wafers have a first electrode surface and a second electrode Surface, a first resonant mirror surface, and a second resonant mirror surface, and the first electrode surface covers a waveguide line of the laser diode wafer, and the second electrode surface is perpendicular to the waveguide line 589772 There is a groove at each end in the straight direction, the first electrode surface of the laser diode wafer is adhered to the second electrode surface adjacent to the laser diode wafer, and the film is coated on the first resonance mirror surface; On the second resonance mirror surface. 1 1. The method of laser diode resonance mirror coating as described in item 10 of the scope of the patent application, wherein the depth and width of the above trenches are at least greater than 5 microns. 1 2. The method of laser diode resonance mirror coating as described in item 10 of the scope of patent application, wherein the groove depth is between 10 and 20 microns. 1 3. The method for coating a laser diode wafer with a resonant mirror as described in item 10 of the scope of the patent application, wherein the width of the second electrode surface is between 60 and less than the length of the resonant cavity of the laser diode wafer. Between 100 microns.