GB2276492A - Mounting structure of optical element - Google Patents

Mounting structure of optical element Download PDF

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Publication number
GB2276492A
GB2276492A GB9403980A GB9403980A GB2276492A GB 2276492 A GB2276492 A GB 2276492A GB 9403980 A GB9403980 A GB 9403980A GB 9403980 A GB9403980 A GB 9403980A GB 2276492 A GB2276492 A GB 2276492A
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Prior art keywords
electrode pads
height
substrate
mounting structure
solder bump
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GB9403980A
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GB9403980D0 (en
Inventor
Yoshinobu Kaneyama
Hiroshi Honmou
Masataka Itoh
Junichi Sasaki
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NEC Corp
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NEC Corp
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Publication of GB2276492A publication Critical patent/GB2276492A/en
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/02—Structural details or components not essential to laser action
    • H01S5/022—Mountings; Housings
    • H01S5/0235—Method for mounting laser chips
    • H01S5/02375—Positioning of the laser chips
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L24/00—Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
    • H01L24/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L24/81—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a bump connector
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K1/00—Soldering, e.g. brazing, or unsoldering
    • B23K1/0008—Soldering, e.g. brazing, or unsoldering specially adapted for particular articles or work
    • B23K1/0016—Brazing of electronic components
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K13/00—Apparatus or processes specially adapted for manufacturing or adjusting assemblages of electric components
    • H05K13/04—Mounting of components, e.g. of leadless components
    • H05K13/046—Surface mounting
    • H05K13/0465—Surface mounting by soldering
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    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/10—Bump connectors; Manufacturing methods related thereto
    • H01L2224/1012—Auxiliary members for bump connectors, e.g. spacers
    • H01L2224/10152—Auxiliary members for bump connectors, e.g. spacers being formed on an item to be connected not being a semiconductor or solid-state body
    • H01L2224/10165—Alignment aids
    • H—ELECTRICITY
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    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/10—Bump connectors; Manufacturing methods related thereto
    • H01L2224/15—Structure, shape, material or disposition of the bump connectors after the connecting process
    • H01L2224/16—Structure, shape, material or disposition of the bump connectors after the connecting process of an individual bump connector
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
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    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/10—Bump connectors; Manufacturing methods related thereto
    • H01L2224/15—Structure, shape, material or disposition of the bump connectors after the connecting process
    • H01L2224/16—Structure, shape, material or disposition of the bump connectors after the connecting process of an individual bump connector
    • H01L2224/161—Disposition
    • H01L2224/16151—Disposition the bump connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive
    • H01L2224/16221—Disposition the bump connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked
    • H01L2224/16225—Disposition the bump connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
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    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/81—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a bump connector
    • H01L2224/8112—Aligning
    • H01L2224/81136—Aligning involving guiding structures, e.g. spacers or supporting members
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    • H01—ELECTRIC ELEMENTS
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    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/81—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a bump connector
    • H01L2224/8112—Aligning
    • H01L2224/81136—Aligning involving guiding structures, e.g. spacers or supporting members
    • H01L2224/81138—Aligning involving guiding structures, e.g. spacers or supporting members the guiding structures being at least partially left in the finished device
    • H01L2224/8114—Guiding structures outside the body
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    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/81—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a bump connector
    • H01L2224/818—Bonding techniques
    • H01L2224/81801—Soldering or alloying
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    • H01L2924/01—Chemical elements
    • H01L2924/01005—Boron [B]
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    • H01L2924/01023—Vanadium [V]
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    • H01—ELECTRIC ELEMENTS
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    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
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    • H01L2924/01024—Chromium [Cr]
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    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/10—Details of semiconductor or other solid state devices to be connected
    • H01L2924/11—Device type
    • H01L2924/12—Passive devices, e.g. 2 terminal devices
    • H01L2924/1204—Optical Diode
    • H01L2924/12042—LASER
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    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/02—Structural details or components not essential to laser action
    • H01S5/0206—Substrates, e.g. growth, shape, material, removal or bonding
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/02—Structural details or components not essential to laser action
    • H01S5/022—Mountings; Housings
    • H01S5/0235—Method for mounting laser chips
    • H01S5/02355—Fixing laser chips on mounts
    • H01S5/0237—Fixing laser chips on mounts by soldering

Abstract

Positioning bases 3a and 3b of SiO2 which are parallel to each other and have height Hx ( mu m) and circular electrode pads 6a, 6b, 6c and 6d each formed by a lamination of a Cr film and an Au film and having diameter of 50 mu m are formed on a silicon substrate 4. The circular electrode pads 6a, 6b, 6c and 6d are separated from each other by a distance which is identical to a distance between adjacent ones of four electrode pads 5 formed on a laser diode chip 1. Solder of AuSn is supplied onto the respective electrode pads 6a, 6b, 6c and 6d and forms semispherical solder bumps 2 when heated. A difference (Hy - Hx) between height Hy of the solder bump 2 measured from the silicon substrate 4 to a top thereof and height Hx of the positioning base 3a (3b) is equal to or larger than a horizontal positional deviation s of the laser diode chip 1 when the latter is temporarily supported by the substrate. The surface tension of the solder adjusts the position of the laser diode chip laterally. <IMAGE>

Description

MOUNTING STRUCTURE OF OPTICAL ELEMENT The present invention relates to a mounting structure of optical elements to be used in an optical module, etc., for optical communication.
In the communication field in which an amount of information is considerably increased, the communication system using electric signal is being switched to an optical communication system which can advantageously accommodate with increased amount of information. Further, nowadays, an application of optical communication to general subscribers is being thought and therefore reduction of price of optical device for optical communication is required. However, in manufacturing such optical device, optical elements such as light emitting element such as semiconductor laser, light receiving element, optical lenses and optical fibers must be mounted on a substrate with their axes being precisely aligned. In order to realize such high precision alignment of the optical axes of the respective optical elements, however, a number of steps for aligning the optical axes are required. In view of reduction of manufacturing cost of optical device, a method of mounting optical elements on a substrate without precise regulation of positions of them has been studied.
In an example of such non-regulation mounting method, solder bumps are formed on a substrate and an optical elements are temporarily put on these bumps. The bumps, melted by heating and adhered to the respective optical elements, change their configuration due to surface tension thereof such that their surface areas become minimum.
As a result, the optical elements are shifted by surface tension of each bump and positioned immediately above the respective solder bumps (self-alignment effect).
An example utilizing this self-alignment effect is introduced in an article "Compact multi-channel LED/PD array modules for hundred Mb/s/ch parallel optical transmission", The Institute of Electronics, Information and Communication Engineers, pages 45 to 50, August 1991.
According to this conventional mounting method of optical elements, accuracy of horizontal positioning with respect to a substrate is high enough due to the selfalignment effect. However, in order to vertically position these optical elements with practically required accuracy of 1 pm, a volume of each solder bump must be controlled with accuracy of 0.1 pg or higher, which is very difficult.
An optical element mounting method for simultaneously positioning optical elements in both horizontal and vertical directions is disclosed by K. P. Jackson et al., "A Compact Multi-channel Transceiver Modules Using Planar Processed Waveguide and Flip-Chip Optoelectronic Components pages 93-97, IEEE, 1992. In the mounting method disclosed in this article, four positioning bases called "stand-offs" are formed on a substrate at positions corresponding to respective four corners of a laser diode chip to be mounted thereon, and the four corners of the chip are grooved correspondingly to loosely fit thereon to thereby provide alignment stops. That is, the chip is put on solder bumps on the substrate with the grooves formed by cutting the four corners of the chip being loosely fit on the respective stand-offs. By heating the substrate, the chip moves horizontally and vertically due to surface tension of molten solder bumps. During this movement of the chip, any of the alignment stops formed by the grooves in the respective four corners of the chip contacts with any corresponding stand-off to prevent a further movement of the chip, completing the positioning.
In this conventional technique in which the horizontal and vertical positioning of the chip is realized by contact of the alignment stops with the stand-offs, the chip can not be secured to a desired position after the solder bumps are melted unless positional accuracy of the four standoffs and dimensional accuracy of the grooves provided in the four corners of the chip are set precisely. Therefore, due to the required high precision of the stand-offs and the grooves, the cost for practicizing this technique becomes very high.
An object of the present invention is to provide a mounting structure for mounting an optical element chip on a substrate precisely without regulation to thereby reduce its manufacturing cost and facilitate a mass production of the structure.
A mounting structure to be described below includes a substrate for mounting an optical element chip having first electrode pads, second electrode pads formed on the substrate at positions corresponding to the respective first electrode pads, solder bumps formed on the respective second electrode pads and receiving the optical element chip, and positioning bases formed on the substrate and having a predetermined height, the optical element chip being rested on the positioning bases after the solder bumps are melted. A relationship between a height Hy of the solder bump with respect to a surface of the substrate, the height Hx of the positioning base and a positional deviation s of the first electrode pad to the second electrode pad is represented by (Hy-Hx) 2 s.
When an optical element chip is mounted with using the mounting structure mentioned above - two steps are required of forming the solder bumps on the respective second electrode pads formed on the substrate and temporarily positioning and putting the first electrode pads of the optical element chip on the solder bumps and of melting the solder bumps by heating. The solder bumps melted by heating spread over surfaces of the second electrode pads and the optical element chip is moved horizontally with respect to a surface of the substrate due to change of their configurations caused by surface tension thereof such that the first electrode pads come immediately above the second electrode pads, respectively, and vertically with respect to the substrate due to reduction of thickness of the solder bumps due to configuration change, so that the optical element chip is rested on the positioning bases provided in the vicinity of the second electrode pads, to complete the vertical positioning.
Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings in which: Fig. i is a plan view of a mounting structure according to an embodiment of the present invention; Fig. 2 is a side view of the mounting structure shown in Fig. 1 when a laser diode chip is mounted on a silicon substrate; Figs. 3A, 3B, 3C and 3D are side views showing bonding steps of the laser diode chip by means of the mounting structure shown in Fig. 1; Fig. 4 shows a method of calculation of a volume of solder bump before bonding; Fig. 5 shows a method of calculation of a volume of solder bump after bonded; Fig. 6 is a plan view of a mounting structure according to a second embodiment of the present invention; Fig. 7 is a plan view of a mounting structure according to a third embodiment of the present invention; and Fig. 8 is a side view of the mounting structure shown in Fig. 7 with a laser diode chip mounted thereon.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Fig. 1 is a plan view of a mounting structure according to an embodiment of the present invention and Fig. 2 is a side view of the mounting structure shown in Fig. 1 when a laser diode chip is mounted.
In these figures, positioning bases 3a and 3b of SiO2 which are parallel to each other have height Hx (pm), and circular electrode pads 6a, 6b, 6c and 6d are respectively formed by a lamination of a Cr film and an Au film and having diameter of 50 pm. The positioning bases and the circular electrode pads are formed on a silicon substrate 4. The circular electrode pads 6a, 6b, 6c and 6d are separated from each other by a distance which is identical to a distance between adjacent ones of four electrode pads 5 formed on a laser diode chip 1.
Solder of AuSn is supplied onto the respective electrode pads 6a, 6b, 6c and 6d to form solder bumps 2. Each solder bump 2 is substantially spherical as shown when an amount of solder supplied is large. However, when an amount of solder supplied is small, its configuration becomes a sphere having an upper portion thereof being cut out.
Length of the positioning base 3a (3b) is substantially the same as length of one side of the laser diode chip 1 to be arranged on the solder bumps 2 and a distance d between the positioning bases 3a and 3b is shorter than the length of one side of the laser diode chip 1. A difference (Hy - Hx) between height Hy of the solder bump 2 measured from the silicon substrate 4 to a top thereof and height Hx of the positioning base 3a (3b) is equal to or larger than a horizontal positional deviation s of the laser diode chip 1 when the latter is temporarily put on the substrate. The positional deviation s is a deviation of the electrode pads 5 from the electrode pads 6a and 6b.
A mounting process for mounting the laser diode chip 1 on the substrate 4 will be described with reference to Figs. 3A to 3D. First, as shown in Fig. 3A, the laser diode chip 1 is temporarily mounted on the solder bumps by a mounting device 100 such that the electrode pads 5 thereof become on the solder bumps, respectively. A positional deviation s during this temporary mounting is about 7 pm. Then, as shown in Fig. 3B, the silicon substrate 4 is heated up to at least a melting point of the solder bumps by a hot plate 200 to melt the solder bumps 2. The molten solder bumps 2 change their configuration by surface tension such that their surface areas become minimum. In this step, as shown in Fig. 3C, the molten solder bumps 2 cause the laser diode chip 1 to move horizontally such that centers of the electrode pads 5 align with center axes of the electrode pads 6a, 6b, 6c and 6d, respectively. During the horizontal movement of the laser diode chip 1, the latter is also moved down to the silicon substrate. A moving distance of the laser diode chip 1 in horizontal direction is about 7 pm which is the positional deviation thereof during the temporary mounting.
A moving distance of the laser diode chip 1 in vertical direction is the difference (Hy - Hx) between the height Hy (pm) measured from the substrate to the top of the solder bump during the temporary mounting and the height Hx of the positioning base 3a (3b). A moving speed of the laser diode chip 1 due to the deformation of solder bumps in horizontal direction is substantially the same as that in vertical direction, and the laser diode chip 1 does not contact with the positioning bases 3 as yet at a time when the horizontal self-alignment completes since the horizontal moving distance is equal to or smaller than the vertical moving distance (Hy - Hx). Therefore, as shown in Fig. 3D, the laser diode chip 1 contacts with the positioning bases 3a and 3b and stops thereat after the horizontal movement thereof is completed. Thus, it is possible to position and solder the laser diode chip 1 with as high accuracy as 1 pm or higher in both horizontal and vertical directions.
In the mounting structure of this embodiment, in order to design the height of the positioning bases such that the vertical moving distance of the laser diode chip 1 is larger than the horizontal moving distance thereof, it is necessary to preliminarily determine the diameter of each electrode pad on the silicon substrate and the volume of each solder bump. Since configuration of each molten solder bump on the electrode pad is very similar to a sphere due to its large surface tension, a molten solder bump is deemed, here, as having a configuration which is a portion of a sphere. As shown in Fig. 4, the following relation is established between volume V of the solder bump, diameter R of the electrode pad and height h of the solder bump during the temporary mounting:
With D in the above equation being ((R/2)2 + h2)/2h, the following equation is obtained: V = sh(4h2 + 3R2)/24 ..... (1) The equation (1) represents a volume of an upper portion of the sphere. When the amount of solder is large as shown in Figs. 1 and 2, its volume is obtained by subtracting the volume V represented by the equation (1) from a volume of the sphere.
From the equation (1), a required amount V of solder is determined on the basis of height h of the solder bump 2 and diameter d of the electrode pad. Then, when height Hx of the positioning base 3a (3b) is to be determined, a change in height of the molten solder bump 2 after the self-alignment, that is, after the laser diode chip is bonded, is calculated. The above-mentioned difference (Hy - Hx) is determined by a result of this calculation.
It is assumed that the configuration of the solder bump after bonded is a sphere an upper and lower portions of which are cut away as shown in Fig. 5 and a volume V thereof is calculated by using height H of the bonded solder bump and diameter d of the electrode pad. In this case, it is assumed that the diameter of the silicon substrate is the same as that of the electrode pad of the laser diode chip and distortion of the solder configuration due to weight of the chip is neglifible. Under these conditions, the volume V can be represented by the following equation:
With D2 in the above equation being (R/2)2 + (H/2)2, the following equation is obtained: V = nH(3R2 + 2H2)/12 ..... (2) Therefore, (Hy - Hx) is set to (h - H) or any other value close thereto. However, at least the relation (Hy - Hx) > s must be satisfied.
According to experiments conducted by the inventors, measured heights h and H of the solder bump before and after bonding to the electrode pads of the silicon substrate are very close to those calculated according to the equations (1) and (2) using preliminarily set solder bump volume V and diameter D of each of the electrode pads of the silicon substrate and a laser diode chip, with errors as small as 2 to 4.8 %.
Fig. 6 is a plan view of a mounting structure according to a second embodiment of the present invention.
In Fig. 6, positioning bases 3a, 3b, 3c and 3d are formed on a silicon substrate with the same height and the same distance d as those of the positioning bases 3a, 3b, 3c and 3d of the mounting structure shown in Fig. 1, respectively.
The positioning bases are not always necessary to have linear configuration and they can have any other configuration and arrangement so long as a laser diode chip can be stably mounted thereon.
Fig. 7 is a plan view showing a third embodiment of the present invention and Fig. 8 is a side view of the mounting structure shown in Fig. 7, with a laser diode chip 1 being mounted. In these figures, circular electrode pads 60a, 60b, 60c and 60d on which solder bumps 2 are provided and positioning bases 30a, 30b, 30c and 30d are arranged alternately along a line (in this case, a square line) on a silicon substrate 4. The relation between height Hx of the positioning base, height of solder bump Hy and horizontal positional deviation s of the laser diode chip 1 mounted on the solder bumps is the same as that in the first embodiment shown in Fig. 1. That is, (Hy - Hx) 2 s is established. In this case, by mounting the chip such that the previously mentioned equations (1) and (2), it is possible to position the laser diode chip 1 with higher accuracy. Since, in the third embodiment, each positioning base is arranged between adjacent solder bumps, utilization efficiency of the surface of the silicon substrate 4 becomes higher.
Although, in the described embodiments, the circular electrode pads are used, their configuration is not limited thereto so long as the relation (Hy - Hx) 2 s is established between height Hx of the positioning base, height Hy of the solder bump and the horizontal deviation s of the laser diode chip. Further, optical element to be mounted on the solder bumps is not limited to the laser diode chip.
It may be an LED or photo diode.
It will be appreciated that arrangements have been described in which an optical element can be mounted easily with high precision, the positional accuracy of the positioning bases is not so critical, and the manufacturing costs can be reduced, making mass production more easy.
Although embodiments of the invention have been described, by way of example, with reference to the accompanying drawings, it will be understood that variations and modifications thereof, as well as other embodiments, may be made within the scope of the appended claims.

Claims (7)

CLAINS
1. A mounting structure for an optical element, including a substrate for mounting an optical element chip which has first electrode pads, second electrode pads on the substrate arranged at positions corresponding respectively to the positions of the first electrode pads, a solder bump on each respective one of the second electrode pads, for mounting the optical element chip, and positioning bases on the substrate, the positioning bases having a predetermined height suitable for supporting the optical element chip stably after the solder bumps supporting the optical element chip have melted, wherein the height Hy of a solder bump measured from a surface of the substrate to the top of the solder bump, the height Hx of a positioning base measured from the surface of the substrate and the positional deviation s of a first electrode pad to a second electrode pad, satisfy the relation (Hy - Hx) 2 s.
2. A mounting structure as claimed in claim 1, wherein the first and the second electrode pads are circular.
3. A mounting structure as claimed in claim 2, wherein the difference (Hy - Hx) between the height Hy of the solder bump measured from the surface of the substrate to the top of the solder bump and the height Hx of the positioning base measured from the surface of the substrate is equal to or very close to a difference (h H) between the height h of the solder bump when the optical element chip is temporarily supported thereby and the height H of the solder bump after bonding, when the following equation is established: V = sh(4h2 + 3R2)/24 = sH(3R2 + 2H2)/12 where V is a volume of each solder bump and R is the diameter of each of the first and the second electrode pads.
4. A mounting structure claimed in claim 1, wherein the positioning bases are formed outside the second electrode pads and extend in parallel to each other by a predetermined distance.
5. A mounting structure as claimed in claim 1, wherein the positioning bases and the second electrode pads are arranged on the substrate alternately along a line at predetermined intervals.
6. A mounting structure as claimed in claim 1, wherein the positioning bases are of insulating material.
7. A mounting structure as claimed in claim 1 substantially as described herein with reference to Figs.
1, 2, 3A, 3B, 3C and 3D, Fig. 6, or Figs. 7 and 8 of the accompanying drawings.
GB9403980A 1993-03-26 1994-03-02 Mounting structure of optical element Withdrawn GB2276492A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5067257A JPH06295937A (en) 1993-03-26 1993-03-26 Mounting method of photoelectric element

Publications (2)

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GB9403980D0 GB9403980D0 (en) 1994-04-20
GB2276492A true GB2276492A (en) 1994-09-28

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EP0840154A1 (en) * 1996-11-05 1998-05-06 Nec Corporation Structure for mounting an optical device
EP0917190A2 (en) * 1997-11-12 1999-05-19 Robert Bosch Gmbh Circuit support board
FR2771321A1 (en) * 1997-11-26 1999-05-28 Commissariat Energie Atomique Method for brazing of two parts used in the connection of a laser diode by the 'flip chip' method.
WO2004015463A1 (en) * 2002-08-09 2004-02-19 Acreo Ab Mirrors for polymer waveguides
WO2005066678A1 (en) * 2003-12-23 2005-07-21 3M Innovative Properties Company Laser submounts with standoff structures
US8086082B2 (en) 2006-07-14 2011-12-27 Koninklijke Philips Electronics N.V. Methods for mounting an electro-optical component in alignment with an optical element and related structures
CN103368062A (en) * 2012-03-26 2013-10-23 鸿富锦精密工业（深圳）有限公司 Wafer-packaging structure and packaging method thereof
CN114784613A (en) * 2022-06-20 2022-07-22 深圳市埃尔法光电科技有限公司 Laser chip with unitized dual-topology structure
CN114784612A (en) * 2022-06-20 2022-07-22 深圳市埃尔法光电科技有限公司 Wafer arrangement method of laser chips with topological structures

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JP2011128290A (en) * 2009-12-16 2011-06-30 Hitachi High-Technologies Corp Light source device, and backlight, exposure device and exposure method using the same

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Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0840154A1 (en) * 1996-11-05 1998-05-06 Nec Corporation Structure for mounting an optical device
US6058234A (en) * 1996-11-05 2000-05-02 Nec Corporation Structure for mounting an optical device
EP0917190A2 (en) * 1997-11-12 1999-05-19 Robert Bosch Gmbh Circuit support board
EP0917190A3 (en) * 1997-11-12 2000-06-14 Robert Bosch Gmbh Circuit support board
FR2771321A1 (en) * 1997-11-26 1999-05-28 Commissariat Energie Atomique Method for brazing of two parts used in the connection of a laser diode by the 'flip chip' method.
WO1999026752A1 (en) * 1997-11-26 1999-06-03 Commissariat A L'energie Atomique Method and device for assembling two structures with a weld bead
WO2004015463A1 (en) * 2002-08-09 2004-02-19 Acreo Ab Mirrors for polymer waveguides
WO2005066678A1 (en) * 2003-12-23 2005-07-21 3M Innovative Properties Company Laser submounts with standoff structures
US8086082B2 (en) 2006-07-14 2011-12-27 Koninklijke Philips Electronics N.V. Methods for mounting an electro-optical component in alignment with an optical element and related structures
CN103368062A (en) * 2012-03-26 2013-10-23 鸿富锦精密工业（深圳）有限公司 Wafer-packaging structure and packaging method thereof
CN114784613A (en) * 2022-06-20 2022-07-22 深圳市埃尔法光电科技有限公司 Laser chip with unitized dual-topology structure
CN114784612A (en) * 2022-06-20 2022-07-22 深圳市埃尔法光电科技有限公司 Wafer arrangement method of laser chips with topological structures
CN114784613B (en) * 2022-06-20 2022-11-11 深圳市埃尔法光电科技有限公司 Laser chip with unitized dual-topology structure

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JPH06295937A (en) 1994-10-21

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