Coherent light generators – Particular active media – Semiconductor
Reexamination Certificate
2001-05-22
2003-05-20
Ip, Paul (Department: 2828)
Coherent light generators
Particular active media
Semiconductor
C372S046012, C372S050121, C372S036000, C438S043000, C385S024000
Reexamination Certificate
active
06567445
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a semiconductor emission element comprising a plurality of emitting portions on the same substrate and a method of manufacturing the same.
2. Description of the Related Art
Today, various kinds of apparatuses such as an optical disk device, a laser-beam printer, a duplicator and so on using a laser diode (LD) which is a semiconductor emission element, have been developed so far. Recently, a high-speed operation and high performance in each of these apparatuses have been sought, and using a plurality of laser beams is thought to be one method for achieving them. For example, reading speed in an optical disk device can be easily made faster through simultaneously reading a plurality of tracks using a plurality of laser beams. Accordingly, developing a semiconductor laser (that is, multi-beam laser) which is able to simultaneously emit a plurality of laser beams has been required.
FIG. 1
shows a disassembled configuration of a multi-beam laser of the related art. The multibeam laser
100
comprises four laser oscillators
120
formed on the same substrate
111
, and each contact electrode
181
formed respectively on a base
180
through each wire
182
is electrically connected to each electrode
115
. However not shown in the figure, each wire connecting portion for connecting an electrode through each wire is respectively provided in each of the wires
182
. Each of the laser oscillators
120
are respectively connected to power source (not shown in figure) through each wire
182
being respectively connected to each of the wire connecting portions.
When manufacturing such a multi-beam laser, first, each of the laser oscillators
120
is respectively formed on the substrate
111
. Next, apart from that, each of the contact electrodes
181
are am respectively formed in the base
180
before respectively connecting each of the laser oscillators
120
formed in the substrate
111
and each of the contact electrodes
181
formed in the base
180
to each other. Accordingly, there is a problem with this multi-beam laser that mass production is difficult since alignment of the position of each of the laser oscillators
120
and each of the contact electrodes
181
becomes difficult when the spaces between each of the laser oscillators
120
become extremely narrow. Recently, an idea of placing the substrate
111
to the base
180
with the laser oscillator
120
side of the substrate
111
placed towards the opposite side of the base
180
has been considered. A multi-beam laser can be easily manufactured without having a problem in alignment of the position if the substrate
111
is made to be supported by the base
180
as described.
However, on the other hand, in a case where the laser oscillator
120
side of the substrate
111
is placed towards the opposite side of the base
180
, radiation of heat generated in each of the laser oscillators
120
becomes more difficult comparing to a case of the related art. For example, in a case where the laser oscillator
120
side of the substrate
111
is placed towards the base
180
side as the related art, the base
180
can serve a radiating function by forming it with a material with high thermal conductivity such as aluminum nitride (AIN) so that heat generated in each of the laser oscillators
120
can be actively radiated through the base
180
. In contrast, in a case where the laser oscillator
120
side of the substrate
111
is placed towards the opposite side of the base
180
, the distance between the laser oscillator
120
and the base
180
becomes further so that the radiating function of the base
180
can not be expected. Accordingly, in a case where the laser oscillator
120
side of the substrate
111
is placed towards the opposite side of the base
180
, there is a problem that threshold current of each of the laser oscillators
120
is increased and the emission power is decreased unless radiation of heat is encouraged in someways.
The invention is designed to overcome the foregoing problems. It is an object to provide a semiconductor emission element which is able to be easily manufactured while encouraging radiation and a method of manufacturing the same.
SUMMARY OF THE INVENTION
A semiconductor emission element of the invention comprises: a base; a substrate supported by the base; a plurality of emitting portions each composed of a plurality of semiconductor layers which are formed by being laminated on the opposite side of the base of the substrate; a plurality of ohmic electrodes respectively provided on the opposite side of the substrate by corresponding to each of the emitting portion while being electrically connected to each of the emitting portion; and at least one radiation layer formed on the ohmic electrodes.
A method of manufacturing a semiconductor emission element of the invention includes the steps of: respectively forming a plurality of emitting portion each made of a plurality of semiconductor layers which area formed by being laminated on a substrate; respectively forming a plurality of ohmic electrodes on each of the emitting portion, which are electrically connected by being corresponded thereto; forming at least one radiation layer on the ohmic electrodes; and supporting the substrate by a base by making the base face the opposite side of the emitting portion of the substrate.
In the semiconductor emission element of the invention, an electric current is flowed into each of the emitting portion through each of the ohmic electrodes and emission occurs in the emitting portion. At this time, generation of heat occurs in the emitting portion, however, the generated heat is actively radiated by a radiation layer. As a result, influence by generation of heat is eliminated and deterioration of the performance of the emitting portion is suppressed.
In a method of manufacturing a semiconductor emission element of the invention, a plurality of emitting portions respectively made of a plurality of semiconductor layers formed by being laminated on a substrate are respectively formed. Further, a plurality of ohmic electrodes are respectively formed on the substrate of each of the emitting portion while at least one radiation layer is formed on the emitting portions. Further, the substrate is supported by a base by making the base face the opposite side of the emitting portions of the substrate.
REFERENCES:
patent: 4567060 (1986-01-01), Hayakawa et al.
patent: 4635268 (1987-01-01), Motegi et al.
patent: 4977570 (1990-12-01), Hasegawa
patent: 5585309 (1996-12-01), Mori et al.
patent: 5608749 (1997-03-01), Kizuki
patent: 5805630 (1998-09-01), Valster et al.
patent: 6052399 (2000-04-01), Sun
patent: 6067310 (2000-05-01), Hashimoto et al.
patent: 6081636 (2000-06-01), Kinoshita
Narui Hironobu
Okano Nobukata
Taniguchi Takehiro
Ueno Noriko
Ip Paul
Jackson Cornelius H
Sonnenschein Nath & Rosenthal
LandOfFree
Method to manufacture a heat emission apparatus in a... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method to manufacture a heat emission apparatus in a..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method to manufacture a heat emission apparatus in a... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3074845