JP2006319011A - Peltier module, and semiconductor laser light-emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To effectively suppress a temperature rise of a semiconductor laser light-emitting device due to heat generation upon driving the device by releasing heat with a small-sized cooling mechanism. <P>SOLUTION: A Peltier module 7 is composed of a plurality of stacked stages of thermoelement layers 21, 22, each of which has p-type thermoelements 20a, n-type thermoelements 20b, and metal electrodes 20c connecting thermoelements 20a, 20b electrically in series. In at least one thermoelement layer 21 out of the stacked stages of thermoelement layers 21, 22; the p-type thermoelements 20a and n-type thermoelements 20b are so connected via the metal electrodes 20c that heat is transmitted in the direction perpendicular to the direction of stacking the stages of thermoelement layers 21, 22. In the other thermoelement layers 21, the p-type thermoelements 20a and n-type thermoelements 20b are so connected via the metal electrodes 20c that heat is transmitted in the direction parallel to the stacking direction of the stages of thermoelement layers 21, 22. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a Peltier module having a cooling capability by the Peltier effect, and to a semiconductor laser light emitting device that performs cooling using the Peltier module.

  In recent years, semiconductor laser light-emitting elements are being widely used in various technical fields. For example, in a device used as a pump light source for an optical amplifier or a light source for a processing device, a plurality of light-emitting points are formed to generate 4 W There has been provided a semiconductor laser light emitting device that achieves higher output than that. FIG. 7 is an explanatory diagram showing a configuration example of a main part of a general high-power semiconductor laser light emitting device. As shown in the figure, the high-power semiconductor laser light emitting device includes a semiconductor laser light emitting element array 31 having a plurality of semiconductor laser elements arranged in a row so that the laser light emission directions are the same. The semiconductor laser light emitting element array 31 is disposed on the base 32 via a submount 33. However, the semiconductor laser light emitting element array 31 is arranged so as to be positioned in the vicinity of the edges of the base 32 and the submount 33. This is to prevent the emitted laser light from interfering with the base 32 or the submount 33 by matching the laser light emitting surface of each semiconductor laser element with the outer edges of the base 32 and the submount 33.

  Incidentally, the semiconductor laser light emitting element array 31 generally generates a large amount of heat. For example, if it is made of a GaAs / AlGaAs infrared semiconductor laser light emitting element, the energy conversion efficiency is 40% to 50%, so that 50% to 60% of the input power is converted into heat. Moreover, if it consists of an AlGaInP / GaInP red semiconductor laser light emitting element, since energy conversion efficiency is 15%-20%, 80%-85% of input electric power is converted into heat. Therefore, the semiconductor laser light emitting element array 31 needs to be used while being cooled. This is because if the heat generated by the semiconductor laser light-emitting element cannot be efficiently dissipated, the temperature of the light-emitting portion rises, further reducing the energy conversion efficiency, and negatively feeding back to reduce reliability.

  The semiconductor laser light emitting element array 31 can be cooled using a Peltier module because a large cooling mechanism such as a forced cooling mechanism using a cooling medium is not required and a reliable cooling effect can be expected.

  A Peltier module is a thermoelectric module that uses electronic cooling utilizing the Peltier effect, and is a unit in which thermoelectric cooling elements, which are junction pairs of p-type thermoelectric elements and n-type thermoelectric elements, are electrically connected in series. Say. 8 and 9 are explanatory diagrams illustrating a basic configuration example of the Peltier module.

  As shown in FIG. 8, in the Peltier module 34, each of the thermoelectric semiconductor elements 34 b and 34 c of the insufficient electron p-type and the excess electron n-type is provided with a metal electrode such as Cu between two insulating electric heating plates 34 a such as ceramics. (However, not shown), the thermoelectric semiconductor elements 34b and 34c are all electrically connected in series. When a direct current power source is connected to the electrode of the Peltier module 34 and a current is passed from the n-type element to the p-type element, heat is absorbed at the upper part of the π-shape due to the Peltier effect, and heat is released at the lower part. At this time, if the direction of the current is reversed, the direction of heat absorption and heat dissipation changes. Utilizing this phenomenon, each thermoelectric semiconductor element 34b, 34c is used as a cooling / heating device.

  Further, as shown in FIG. 9, the Peltier module 34 is configured by stacking a plurality of thermoelectric element layers 34d in which thermoelectric semiconductor elements having a Peltier effect are arranged between insulated electric heating plates so that the heat flow is in one direction. A multi-stage configuration has also been proposed (see, for example, Patent Documents 1 and 2). This is because if the multi-stage configuration is such that the heat flow is in one direction, the amount of heat absorbed is large, so that the temperature difference during cooling can be increased.

Japanese Patent Laid-Open No. 10-190071 JP 2004-158582 A

However, when the semiconductor laser light emitting element array 31 is cooled using the Peltier module 34, the semiconductor laser light emitting element array 31 is located in the vicinity of the edges of the base 32 and the submount 33. There are difficulties in terms. That is, when the semiconductor laser light emitting element array 31 is positioned in the vicinity of the edges of the base 32 and the submount 33, even if the Peltier module 34 can cool the entire surface of the base 32, Only a part of the cooling capacity of the Peltier module 34 contributes to the cooling of the semiconductor laser light emitting element array 31.
Regarding this point, it is conceivable to improve the cooling efficiency by arranging the semiconductor laser light emitting element array 31 not in the vicinity of the edge of the base 32 but in the vicinity of the central portion. However, if the semiconductor laser light emitting element array 31 is arranged near the center of the base 32, the laser light emitted from the semiconductor laser light emitting element array 31 interferes with the Peltier module, and the quality of the emitted laser light is degraded. It is not appropriate because there is a possibility.
Even when the semiconductor laser light emitting element array 31 is arranged near the edge of the base 32, the number of stages of the thermoelectric element layer 34d having a multistage structure in the Peltier module 34 is increased to increase the heat absorption amount, thereby cooling Although it is conceivable to compensate for the deterioration in efficiency, in that case, the entire thickness of the Peltier module 34 becomes large, so that it is very difficult to downsize the entire apparatus. Therefore, it becomes unsuitable especially for uses such as a portable laser irradiation apparatus.

  SUMMARY OF THE INVENTION Accordingly, the present invention provides a Peltier module and a semiconductor laser light emitting device capable of suppressing the temperature rise due to heat generation during driving of the semiconductor laser light emitting element efficiently and by exhausting heat with a small cooling mechanism. With the goal.

  The present invention is a Peltier module devised to achieve the above object, in which a plurality of thermoelectric element layers each having a p-type thermoelectric element, an n-type thermoelectric element, and a metal electrode electrically connecting them in series are stacked. In the Peltier module configured as described above, at least one thermoelectric element layer of the plurality of stages moves the p-type thermoelectric element and the n so as to move heat in a direction orthogonal to the stacking direction of the plurality of stages. Type thermoelectric elements are connected by the metal electrodes, and the other thermoelectric element layers are arranged such that the p-type thermoelectric elements and the n-type thermoelectric elements move heat in a direction parallel to the stacking direction of the plurality of stages. It is connected by the metal electrode.

  In the Peltier module configured as described above, at least one thermoelectric element layer moves heat in a direction orthogonal to the stacking direction of the thermoelectric element layers in a plurality of stages. Therefore, for example, even when a heat source is arranged in the vicinity of the edge when the thermoelectric element layer is viewed in plan, the heat generated by the heat source is orthogonal to the stacking direction of the thermoelectric element layers in a plurality of stages. Due to the heat transfer in the direction, the entire thermoelectric element layer is diffused. That is, the heat from the heat source in the vicinity of the edge is actively equalized throughout the Peltier module.

As described above, in the Peltier module of the present invention and the semiconductor laser light emitting device using the Peltier module, the semiconductor laser light emitting element array is arranged in the vicinity of the edge of the Peltier module in order to avoid degradation of the quality of the emitted laser light. Even when the semiconductor laser light emitting element array is driven, heat generated when the semiconductor laser light emitting element is driven is actively diffused and made uniform over the entire Peltier module. Therefore, it is possible to exhaust heat by efficiently using the cooling capacity of the Peltier module, and as a result, efficient cooling can be realized. Moreover, since efficient cooling can be realized, the number of stages of the multi-layered thermoelectric element layer in the Peltier module can be minimized, and the increase in the overall thickness of the Peltier module can be suppressed as much as possible. it can.
As described above, according to the Peltier module and the semiconductor laser light emitting device of the present invention, the temperature rise due to the heat generated when the semiconductor laser light emitting element is driven can be efficiently suppressed by exhausting heat with a small cooling mechanism. It can be done.

  Hereinafter, a Peltier module and a semiconductor laser light emitting device according to the present invention will be described with reference to the drawings.

  First, an outline of the semiconductor laser light emitting device will be described. FIG. 1 is an explanatory diagram showing a schematic configuration example of a semiconductor laser light emitting device according to the present invention. As shown in the figure, the semiconductor laser light emitting device described here includes a semiconductor laser light emitting element array 1, and the semiconductor laser light emitting element array 1 is disposed on a base 2 via a submount 3. Yes. Since the base 2 is used as a heat sink, it is formed from a metal material having a high thermal conductivity such as Cu. For the submount 3, a material having a high thermal conductivity such as SiC (silicon carbide), CuW (copper tungsten), diamond or the like is selected.

  The semiconductor laser light emitting element array 1 has a plurality of semiconductor laser elements (not shown) arranged in a line so that the emission directions of the laser light are the same, and is a so-called semiconductor laser light emitting element bar (LD bar). It is called. Solder is used for fixing the semiconductor laser light emitting element array 1 on the submount 3 and fixing the submount 3 on the base 2. Specifically, for example, a metal melt such as AuSn (gold tin) solder is vapor-deposited on the surface of the submount 3 to a thickness of about 3 μm to 6 μm, and the semiconductor laser light emitting element array 1 is heated and placed on the solder. Is melted to join the semiconductor laser light emitting element array 1 and the submount 3 together. The same applies between the submount 3 and the base 2.

Here, the semiconductor laser elements constituting the semiconductor laser light emitting element array 1 will be described. FIG. 2 is a perspective view schematically showing an example of the chip structure of the semiconductor laser element. As shown in the figure, each of the semiconductor laser elements constituting the semiconductor laser light emitting element array 1 has an n-type first buffer layer 12, n on a n-type GaAs plate 11 having a substrate thickness of, for example, 80 μm to 100 μm. Type second buffer layer 13, n-type clad layer 14, active layer / guide layer 15, p-type clad layer 16 and p-type cap layer 17 are laminated in this order from the bottom layer. It has a structure. The first buffer layer 12 is formed of, for example, an n-type GaAs layer having a thickness of 0.5 μm. The second buffer layer 13 is formed of, for example, an n-type Al _0.3 Ga _0.7 As layer having a thickness of 0.5 μm. The n-type cladding layer 14 is formed of, for example, an n-type Al _0.47 Ga _0.53 As layer having a thickness of 1.8 μm. The p-type cladding layer 16 is formed of, for example, a p-type Al _0.47 Ga _0.53 As layer having a thickness of 1.8 μm. The cap layer 17 is formed of, for example, a p-type GaAs layer having a thickness of 0.5 μm. The active layer / guide layer 15 includes an Al _0.3 Ga _0.7 As guide layer having a thickness of 60 nm to 65 nm, an Al _0.14 Ga _0.86 As active layer having a refractive index larger than that of the guide layer and a thickness of 10 nm, and a thickness of 60 nm. It is configured as a three-layer laminated film with an Al _0.3 Ga _0.7 As guide layer of 65 nm or less.
Further, in the laminated film having such a DH junction laminated structure, a current non-injection region 18 is formed on both sides of the cap layer 17 and the p-type cladding layer 16 which become current injection regions. The current non-injection region 18 is formed, for example, by digging the cap layer 17 and the p-type cladding layer 16 and embedding an n-type GaAs layer in the digging region.
Further, a p-side electrode 19 a is formed on the cap layer 17 and the current non-injection region 18. For example, the p-side electrode 19a is formed of a metal laminated film including a Ti layer, a Pt layer, and an Au layer from the cap layer 17 side.
On the other hand, an n-side electrode 19b is formed on the n-type GaAs plate 11 side. The n-side electrode 19b is formed in the order of, for example, an Au—Ge layer, a Ni layer, and an Au layer from the n-type GaAs plate 11 side. Therefore, the upper portion of the p-type cladding layer 16 and the cap layer 17 are formed as a wide stripe ridge-shaped body having a wide width, for example, a stripe width W of 100 μm, and both sides of the ridge-shaped body are current non-injection regions 18. ing. The current non-injection region 18 is formed with a width of 50 μm, for example.

  Such semiconductor laser elements are arranged in a line so that the emission directions of the laser beams are the same to constitute the semiconductor laser light emitting element array 1.

  As shown in FIG. 1, each semiconductor laser element in the semiconductor laser light emitting element array 1 has a bonding wire 6 between a conductive block 5 made of Cu or the like fixed on a base 2 via an insulating plate 4. Bonded. That is, in order to supply a current to each semiconductor laser element, the negative (−) electrode of each semiconductor laser element and the conductive block 5 are connected. The bonding wire 6 is formed of, for example, an Au wire or an Au foil. An insulating plate 4 is disposed between the base 2 and the conductive block 5 in order to insulate the negative (−) electrode of the conductive block 5 from the positive (+) electrode of the base 2 on the submount 3 side. However, the insulating plate 4 is made of an insulating resin such as glass or epoxy.

  On the other hand, a Peltier module 7 is disposed on the side of the base 2 opposite to the mounting surface of the semiconductor laser light emitting element array 1, that is, the lower surface side. That is, the semiconductor laser light emitting element array 1 is arranged on the Peltier module 7 via the base 2 and the submount 3 having thermal conductivity. At this time, the base 2 is brought into contact with, for example, an aluminum plate of the Peltier module 7 using grease (not shown) having high thermal conductivity, and a sufficient thermal contact is obtained by pressing a screw or a spring. It shall be.

  However, in order to avoid the Peltier module 7, the base 2 or the submount 3 from interfering with the laser light emitted from the semiconductor laser light emitting element array 1, the semiconductor laser light emitting element array 1 includes the Peltier module 7, base 2 and the submount 3 are arranged so as to be positioned in the vicinity of the edge when viewed in plan. More specifically, the positional relationship between the semiconductor laser light-emitting element array 1 and the Peltier module 7 is set so that the end surface on the laser light emitting side of the semiconductor laser light-emitting element array 1 is positioned near the edge.

  In addition, a temperature adjustment circuit 8 is connected to the Peltier module 7. The temperature adjustment circuit 8 performs drive control (supply current control) of the Peltier module 7 based on the detection result of the temperature detection means 9 such as a thermistor for detecting the temperature of the base 2. By this drive control, the temperature of the semiconductor laser light emitting element array 1 is maintained at a predetermined target value. Note that the temperature adjustment circuit 8 and its drive control, and the temperature detection by the temperature detection means 9 may be realized by using a known technique, and therefore the description thereof is omitted here.

  Next, the configuration of the Peltier module 7 will be described. FIG. 3 is an explanatory view showing a schematic configuration example of the Peltier module according to the present invention, and FIGS. 4 and 5 are plan views showing a configuration example of the main part thereof.

  As shown in FIG. 3, the Peltier module 7 is configured by stacking a plurality of thermoelectric element layers 21 and 22 in which a p-type thermoelectric element 20 a and an n-type thermoelectric element 20 b are electrically connected in series. . In the illustrated example, the two-stage thermoelectric element layers 21 and 22 are given as an example, but three or more stages may be stacked. However, in the following description, a case of a two-stage configuration is taken as an example.

  Of the two-stage thermoelectric element layers 21, 22, the thermoelectric element layer 21 in contact with the base 2, that is, the uppermost thermoelectric element layer (hereinafter referred to as “uppermost thermoelectric element layer”) 21, as shown in FIGS. 4 and 5 In addition, the p-type thermoelectric elements 20a and the n-type thermoelectric elements 20b are alternately arranged horizontally (in a state where the longitudinal direction extends horizontally). The laterally arranged p-type thermoelectric element 20a and n-type thermoelectric element 20b are connected to each other by a metal electrode 20c made of a conductive material such as Cu. Joining between the p-type thermoelectric element 20a and the n-type thermoelectric element 20b and the metal electrode 20c is performed via solder 20d. In addition, the p-type thermoelectric element 20a, the n-type thermoelectric element 20b, and the metal electrode 20c are not bonded to the lateral surface, so that they are not electrically connected to other parts, for example, an organic system such as a fluororesin, or An oxide-based material such as a SiO-based paint is applied. Thus, in the uppermost thermoelectric element layer 21, the p-type thermoelectric elements 20a and the n-type thermoelectric elements 20b are alternately connected by the metal electrodes 20c, and finally all are electrically connected in series.

  When the p-type thermoelectric element 20a and the n-type thermoelectric element 20b placed horizontally are electrically connected in series via the metal electrode 20c, a DC power source is connected to the electrode (not shown) of the uppermost thermoelectric element layer 21. Thus, when a current flows from the n-type thermoelectric element 20b to the p-type thermoelectric element 20a, heat absorption occurs on the left side in FIG. 4 and heat dissipation occurs on the right side due to the Peltier effect. As a result, in the uppermost thermoelectric element layer 21, heat is forcibly moved in the horizontal direction in the plane.

  That is, in the uppermost thermoelectric element layer 21, the p-type thermoelectric element 20 a and the n-type thermoelectric element 20 b are placed horizontally so as to move heat in a direction perpendicular to the stacking direction of the two-stage thermoelectric element layers 21 and 22. Thus, the metal electrode 20c is electrically connected in series. In the case of a configuration in which three or more stages are stacked, the uppermost thermoelectric element layer 21 may have at least one layer. However, it is desirable that the one layer is located on the uppermost stage in contact with the base 2.

  On the other hand, other thermoelectric element layers 22 excluding the uppermost thermoelectric element layer 21, that is, a thermoelectric element layer (hereinafter referred to as a “lower thermoelectric element layer”) 22 located below the uppermost thermoelectric element layer is shown in FIG. Thus, both the p-type thermoelectric element 20a and the n-type thermoelectric element 20b are arranged vertically (in a state where the longitudinal direction extends vertically). The vertically placed p-type thermoelectric element 20a and n-type thermoelectric element 20b are electrically connected in series by a metal electrode (not shown).

  When the vertically placed p-type thermoelectric element 20a and n-type thermoelectric element 20b are electrically connected in series via a metal electrode, a DC power source is connected to the electrode (not shown) of the lower thermoelectric element layer 22 When current flows from the n-type thermoelectric element 20b to the p-type thermoelectric element 20a, heat is absorbed in the upper part in FIG. 4 and heat is dissipated in the lower part due to the Peltier effect. Thereby, in the lower thermoelectric element layer 22, heat is forced to move from the upper part toward the lower part along the vertical direction.

  That is, in the lower thermoelectric element layer 22, the p-type thermoelectric element 20 a and the n-type thermoelectric element 20 b are placed vertically and horizontally so as to move heat in a direction parallel to the stacking direction of the two-stage thermoelectric element layers 21 and 22. Thus, the metal electrodes are electrically connected in series.

  A member having thermal conductivity, such as an aluminum plate, between the uppermost thermoelectric element layer 21 and the lower thermoelectric element layer 22 so that the heat of the uppermost thermoelectric element layer 21 can be exhausted to the lower thermoelectric element layer 22. 23 is arranged.

  For the uppermost thermoelectric element layer 21 and the lower thermoelectric element layer 22 as described above, the temperature adjustment circuit 8 supplies current to the respective electrodes, and the current value supplied to each electrode is set to a preset program. Shall be allocated based on That is, the temperature adjustment circuit 8 determines how much current value flows through each of the uppermost thermoelectric element layer 21 and the lower thermoelectric element layer 22 while following a preset program.

  Next, an example of processing operation in the semiconductor laser light emitting device and the Peltier module 7 configured as described above will be described.

  In the semiconductor laser light emitting device, when the semiconductor laser light emitting element array 1 is driven to emit laser light to each semiconductor laser element in the semiconductor laser light emitting element array 1, heat is generated from the semiconductor laser light emitting element array 1. The generated heat is transmitted to the Peltier module 7 via the base 2 and the submount 3 having thermal conductivity. When the temperature detection means 9 detects the heat, the temperature adjustment circuit 8 starts supplying current to the Peltier module 7 while driving the Peltier module 7 while following a preset program.

  At this time, in the Peltier module 7, the heat from the semiconductor laser light emitting element array 1 is first transmitted to the uppermost thermoelectric element layer 21 in contact with the base 2. However, the uppermost thermoelectric element layer 21 is configured to move the heat in the horizontal direction in the plane. Therefore, when the temperature adjustment circuit 8 starts supplying current to the Peltier module 7, the heat transferred from the semiconductor laser light-emitting element array 1 to the Peltier module 7 is spread over the entire thermoelectric element layers 21 and 22 by moving in the horizontal direction. Will be spread. That is, the heat from the semiconductor laser light-emitting element array 1 is actively made uniform throughout the Peltier module 7.

  The lower thermoelectric element layer 22 located below the uppermost thermoelectric element layer 21 is configured to move heat from the upper part toward the lower part along the vertical direction. Therefore, when the temperature adjustment circuit 8 starts supplying current to the Peltier module 7, the heat diffused in the uppermost thermoelectric element layer 21 is transferred to the lower thermoelectric element layer 22, and further to the lower portion by the lower thermoelectric element layer 22. Will be moved towards. That is, the heat from the semiconductor laser light-emitting element array 1 is radiated to the lower side of the lower thermoelectric element layer 22 by moving in the vertical direction in the lower thermoelectric element layer 22 after being diffused in the uppermost thermoelectric element layer 21. It is.

  As described above, in the Peltier module 7 and the semiconductor laser light emitting device using the Peltier module 7 described in the present embodiment, the uppermost thermoelectric element layer 21 of the two-stage thermoelectric element layers 21 and 22 horizontally heats. It moves in the direction and spreads. Therefore, in order to avoid the Peltier module 7, the base 2 or the submount 3 from interfering with the laser light emitted from the semiconductor laser light emitting element array 1 and degrading the quality of the emitted laser light, the semiconductor laser light emission is performed. Even when the element array 1 is arranged in the vicinity of the edges of the Peltier module 7, the base 2 and the submount 3, the heat generated when the semiconductor laser light emitting element in the semiconductor laser light emitting element array 1 is driven is the highest thermoelectric power. Since the element layer 21 actively diffuses and equalizes the entire area of the Peltier module 7, only a part of the cooling capacity does not contribute to cooling as in the conventional case, and the cooling capacity of the Peltier module 7 is efficiently It becomes possible to perform exhaust heat by using it, and as a result, efficient cooling can be realized. Moreover, since efficient cooling can be realized, the number of stages of the thermoelectric element layers 21 and 22 in the Peltier module 7 can be minimized as in a two-stage structure, for example, and the overall thickness of the Peltier module 7 can be reduced. Can be suppressed as much as possible.

  That is, according to the Peltier module 7 and the semiconductor laser light emitting device described in the present embodiment, the temperature rise due to heat generated when the semiconductor laser light emitting element array 1 is driven can be efficiently exhausted by a small cooling mechanism, It can be suppressed.

  In particular, as described in the present embodiment, if the uppermost thermoelectric element layer 21 is configured to perform heat transfer in the horizontal direction, heat at the time of driving the semiconductor laser light emitting element array 1 is first diffused. Then, since the heat is radiated downward, it is very suitable for ensuring efficient cooling.

  Here, the cooling capability of the Peltier module 7 and the semiconductor laser light emitting device described in the present embodiment will be described with specific examples. FIG. 6 is an explanatory diagram showing a specific configuration example of the semiconductor laser light emitting device.

  As shown in the figure, a semiconductor laser light emitting element array 1 is arranged on a Peltier module 7 via a base 2 and a submount 3, and the semiconductor laser light emitting element array 1 is composed of a Peltier module 7, a base 2 and a submount. In the semiconductor laser light emitting device located in the vicinity of the edge of 3, generally, the thicker the base 2, the smaller the temperature difference before and after the laser light emission direction in the base 2. Therefore, for example, if the Peltier module 7 is configured as in the prior art, the temperature of the semiconductor laser light emitting element array 1 is increased by increasing the thickness of the base 2 and reducing the temperature difference before and after the laser light emission direction. Can also be lowered. For example, if the amount of heat generated by the semiconductor laser light-emitting element array 1 is about 34 W, the base 2 having a size of 14 mm in the laser light emission direction with respect to the submount 3 having a thickness of 0.3 mm as shown in the figure. If the thickness is 5 mm, the temperature difference between the upper and lower surfaces of the base 2 is about 10 ° C., and the temperature difference before and after the laser beam emission direction is about 5 ° C.

  On the other hand, if the Peltier module 7 has a two-stage configuration as described in the present embodiment, and the uppermost thermoelectric element layer diffuses by moving the heat in the horizontal direction, the base 2 Even if the thickness is 2.5 mm, the temperature difference between before and after the laser light emission direction of the base 2 becomes about 2 ° C. due to the horizontal heat transfer. The temperature difference between the upper and lower surfaces of the base 2 is about 4 ° C. due to the efficient cooling accompanying the reduction of the difference between the front and rear. Therefore, if the Peltier module 7 having the configuration described in the present embodiment is used, the temperature in the semiconductor laser light-emitting element array 1 can be lowered by about 6 ° C. as compared with the conventional thickness base. In addition, since the thickness of the base 2 can be reduced and the number of stages of the thermoelectric element layers in the Peltier module 7 is minimized, it is very suitable for downsizing the semiconductor laser light emitting device. .

  In the present embodiment, the preferred specific examples of the present invention have been described. However, the present invention is not limited to the contents, and can be appropriately changed without departing from the gist thereof. For example, the present invention can be applied not only to GaAs / AlGaAs but also to AlGaInP and AlGaInN semiconductor laser light emitting devices.

It is explanatory drawing which shows the schematic structural example of the semiconductor laser light-emitting device concerning this invention. It is a perspective view which shows typically the example of the chip structure of a semiconductor laser element. It is explanatory drawing which shows the schematic structural example of the Peltier module which concerns on this invention. It is a top view which shows the structural example of the principal part of the Peltier module which concerns on this invention (the 1). It is a top view (the 2) which shows the structural example of the principal part of the Peltier module which concerns on this invention. It is explanatory drawing which shows the specific structural example of a semiconductor laser light-emitting device. It is explanatory drawing which shows the principal part structural example of a general high output semiconductor laser light-emitting device. It is explanatory drawing (the 1) which shows the basic structural example of the conventional Peltier module. It is explanatory drawing (the 2) which shows the basic structural example of the conventional Peltier module.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Semiconductor laser light-emitting element array, 2 ... Base, 3 ... Submount, 7 ... Peltier module, 20a ... P-type thermoelectric element, 20b ... N-type thermoelectric element, 20c ... Metal electrode, 21 ... Top thermoelectric element layer, 22 ... Lower thermoelectric element layer

Claims (3)

A Peltier module configured by stacking a plurality of thermoelectric element layers having a p-type thermoelectric element, an n-type thermoelectric element, and a metal electrode that electrically connects them in series,
The p-type thermoelectric element and the n-type thermoelectric element are connected by the metal electrode so that at least one thermoelectric element layer of the plurality of stages moves heat in a direction orthogonal to the stacking direction of the plurality of stages. And
In the other thermoelectric element layer, the p-type thermoelectric element and the n-type thermoelectric element are connected by the metal electrode so as to move heat in a direction parallel to the stacking direction of the plurality of stages. Peltier module. On a Peltier module formed by stacking a plurality of layers of thermoelectric element layers having p-type thermoelectric elements, n-type thermoelectric elements, and metal electrodes that electrically connect them in series, via a supporting member having thermal conductivity A semiconductor laser light emitting element array in which a plurality of semiconductor laser light emitting elements emitting laser light are arranged in an array, and the semiconductor laser light emitting element array is in the vicinity of an edge of the support member and the Peltier module A semiconductor laser emitting device located at
The Peltier module is
The p-type thermoelectric element and the n-type thermoelectric element are connected by the metal electrode so that at least one thermoelectric element layer of the plurality of stages moves heat in a direction perpendicular to the stacking direction of the plurality of stages. And
The p-type thermoelectric element and the n-type thermoelectric element are connected by the metal electrode so that another thermoelectric element layer moves heat in a direction parallel to the stacking direction of the plurality of stages. Semiconductor laser light emitting device. Of the plurality of thermoelectric element layers, the p-type thermoelectric element and the n-type thermoelectric element are arranged such that the uppermost thermoelectric element layer in contact with the support member moves heat in a direction perpendicular to the stacking direction of the plurality of stages. The element is connected by the metal electrode. The semiconductor laser light emitting device according to claim 2.

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