JPS58111387A - Laser diode - Google Patents

Abstract

PURPOSE:To facilitate the connection work of a photosensor chip, and to improve yield by reducing the angle of inclination of the photosensor chip set up to a flange. CONSTITUTION:A laser diode chip 5 is fixed to the side surface of a stem 3 set up protrusively at the center of the main surface of the flange 2 through a sub- mount 4 while the main surface side of the flange is sealed with a package member with a transparent window 10, and the photosensor chip 7 detecting laser beams 6 emitted from the rear end of the chip 5 is disposed onto the main surface of the flange. The photosensor chip 7 is inclined lest laser beams 6 reflected from the surface of the photosensor chip 7 should reach a transparent window region while a displacement W is formed between an end edge at the light reception side of the photosensor chip 7 and the extension line of a projecting section projecting the laser beams of the laser diode chip 5 in order to decrease the angle of inclination.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a laser diode, a %-oscillating laser t
rRegarding a laser diode included in a photo sensor for monitoring.

As shown in Figure 1, an L/-f-diode is on the market for use as a source pickup for optical video discs, in which a photosensor for a laser source monitor is incorporated in the same package. As shown in the figure, this laser diode 1 is made of a metal with good conductivity.
The main surface of the stem 3 made of a metal with good thermal conductivity built in the center of the main surface (upward) of the lunge 2 (right 1Illv7B)
A laser diode chip 5 is fixed to it via a buffer plate (submount) It. The buffer plate 4 absorbs thermal stress t- due to the difference in thermal gs rate between the laser diode chip 5 and the stem 3, thereby preventing damage to the chip. Laser light 6 is emitted from the upper and lower ends of chip 5, respectively. Additionally, a photosensor (photosensor chip) 7 consisting of a bin diode for monitoring a laser beam 6t oscillated from the lower end (rear end) of the chip 5 is fixed on the flange 2. 17T17A metal inner cover (package member) 8 is airtightly attached to the main surface of the flange 2 by ring welding or the like! l! has been stopped. The upper part of the middle yup 8 is opened, and this opening Kt! a! A clear glass plate 9 is attached airtight to form a transparent window 10. In addition, although not described in detail, three 7tFia leads 11 are insulated (in some cases, one conductive one is fixed through the main surface of the flange 2) to the flange 2, and the leads 11 protrude from the main surface of the flange 2. The end is electrically connected to the electrode portion of the photo sensor 7 and laser diode chip 5 corresponding to the end 91g by a wire (not shown).

By the way, in a laser diode having such a structure, the laser light 6 oscillated from the upper end (tip 1111) of the laser diode chip 5 is emitted from the transparent window 10ρ, and the laser light 6 is emitted from the rear end of the laser diode chip 5. The reflected laser -ffi12 reflected by the photosenner 7 at tRthi also emits light. As a result,
The laser beam 6 emitted from the laser diode chip 5 and the reflected laser beams f and 12 that have returned to the front cause interference, resulting in a wave field pattern (laser beam 1).
The intensity distribution shape of the directional output beam is disturbed, and the optical coupling adjustment becomes deceptive when the laser diode is integrated into the video disk. Note that in the photosensor 7, reflection occurs not only at the electrode but also at the guard ring portion.

In order to eliminate such defects, a person should tilt the photosensor chip 7Yr as shown in FIG. 2 so that the source reflected on the surface of the photosensor chip 70 is Without reaching A window 10,
We are proposing a structure that reaches the inner wall surface of the cap.

By the way, in order to make the reflection ft spread over the transparent window 106'C, the height and size of the transparent window 10 from the flange surface, the height of the laser diode chip 5 from the flange surface, and Although it varies depending on the location etc.
Inclination angle of photo sensor chip 7 to 7 lunge 2 with m #
has a degree of 10 degrees.

- 10,000 Photo Dragon Search Tip 7 When fixing to 7 langes with an automatic machine or the like, since the bevel angle # of the plate is as large as 10 degrees, it becomes difficult to join, resulting in a new problem of low yield.

On the other hand, the present inventors have obtained the results of various experiments and ideas.

I have learned that the farther the photo sensor chip 7 is mounted from directly below the laser diode chip 5, the smaller the mounting angle becomes.

Therefore, the object of the present invention is to
Additional inclination angle to lunge! ? By making it smaller, the connection work of the photosensor chip can be made easier, and the yield rate can be reduced.
KToru aims to improve the society.

In order to achieve such an object, the present invention fixes the radar diode chip via the 1IIiK nap mount of the stem protruding from the center of the main surface of the flange, and
7. In a laser diode, the main surface of the flange is sealed with a package member having a transparent window, and a photosenner chip is disposed on the main surface of the flange to detect a laser beam tube emitted from the rear end of the laser diode chip. , the laser beam reflected on the IR surface of the photosensor chip passes through the package member 1! In order to prevent the photo sensor chip from reaching 1mK, the photo sensor chip T# is tilted, and in order to make the #l bevel tube smaller, the photo sensor chip's receiving end is made smaller and the laser diode chip's laser diode chip's laser main tube is extended. A deviation Wt is provided at the intersection of .

FIG. 3 Enlargement of a laser diode according to an embodiment 91 of the present invention! ! FIG. Similar to the radar diode shown in stripe 2, this laser diode is sub-mounted on one part (111ii) of the stem 3 which is vertically installed on the main surface of the 7-tune 2. The rear end of 5 (
Lower jilt) K is fixed to the main surface of the flange so as to face each other and have a #1M angle #1.

The output section for receiving and receiving the laser beam 6 of the primary laser diode chip 5 is located at Napmakunt's Chip Sanmura #Kl! ss
It is close to. In addition, in this ritual, the photosensor chip 7 is fixed to the flange 2 so that a dislocation W occurs between the receiving part of the photosensor chip 70 and the extended edge of the emitting part of the laser diode chip 5. ing. In addition, the main surface fog of 7 lunge 2 is the ceiling 11 Kal light window 1
The metal cap 8 is airtightly closed by a metal cap K11, and a predetermined electrode (not shown) of each chip 5.7 and a predetermined lead 11 are connected by a wire (conductor II) not shown.

By the way, the above-mentioned deviation W is assumed to be, for example, a maximum of 0.4 x 0.5 x. In this case, the mounting inclination angle θ of the photosensor chip 7 is lsfwII! Blind can be made small. In addition, the dimensions of the main parts of the real m moth are as shown in the table below.

Further, as shown in FIG. 5, the deviation WO value can be determined under the condition that the detection current N of the photosensor is 0.2 mm or more when the laser light output Po is 3 W. If the detection current of the photosensor is less than 0.2W4m, there is a possibility that the control accuracy of the laser light output of the radar diode chip 5 will be reduced.

In addition, the mounting inclination angle θ varies depending on the size of the transparent window 10 or the size K of the light receiving area at the time of the original III meeting with the original fiber, but it is necessary to set the reflection angle a to be larger than 20°, for example. Must be set! In this case, as shown in FIG. 4, the inclination angle # is at least 5 degrees.

In addition, Figure jI4 shows each deviation W due to the difference in the mounting inclination angle θ.
The graph showing the relationship between the reflection angle and the angle of reflection at K is a graph showing the relationship between the detection current N and (corner) of the 7th angle sensor at each shift W4C.According to this implementation, The light reflected from the photosensor chip surface of the radar source for the monitor is reflected outside through the transparent window.
Since no radiation is emitted, the far-field pattern of the laser diode remains stable without being disturbed.

In the implementation of the experiment, as a result of the extension layer of the emitting part that emits light from the edge of the photo sensor chip, it is easy to attach the position to the 7 range of the photosensor chip. Reduces the number of defects in Australia.

Note that the present invention is not limited to the above-mentioned example. In other words, there are no limitations on the cage with respect to the displacement W of the photosensor chip or the mounting angle of inclination.

As described above, according to the present invention, it is possible to improve the installation step w of the photosensor chip, thereby reducing costs.

Further, according to the present invention, since the far-field pattern is stable, a high quality radar diode can be provided.

[Brief explanation of drawings]

Figure 1 is an *S cross-sectional view of a conventional laser diode, Figure 2 is a cross-sectional view of a conventional laser diode.
The figure shows the lI of a laser diode already proposed by Honde.
FIG. 113 is a cross-sectional view of a laser diode according to an embodiment of the present invention, and FIGS. 114 and 5 are graphs showing the correlation between the reflection angle α and the detected current knee with respect to the deviation W. 2...7 lunge, 3...stem, 4...submount, 5...laser diode chip, 6...laser source, 7...photo sensor chip, 10...
Transparent window, 12...Reflection radar source. Agent Attorney Susuki 1) Li *-nee, 1, (j・,
:, −′/

Claims (1)

[Claims] A laser diode chip is fixed to the adhesive surface of the stand by protruding from the center of the main surface of the 1 and 7 rungs via a submount, and the raw surface of the 7 rung is fixed with a package member having a transparent window. , and a laser diode is provided with a photo-series chip for detecting the laser light emitted from the rear end of the radar diode chip on the main surface of the flange, and the laser light reflected from the surface of the photosensor chip is In order to avoid fiL in the Miass area of the package member, the photosensor chip tm* is made small, and in order to reduce the angle of inclination, the photosensor chip's light receiving 1131111 edge and the laser diode chip's laser beam emitting part are extended lI& Providing a shift wl between the layers 1-Characteristics of the laser diode.