JP4197113B2 - Semiconductor carrier and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention comprises a sintered body of a WCu alloy or a MoCu alloy having a low coefficient of thermal expansion and high heat dissipation. Semiconductor carrier and manufacturing method thereof About.
[0002]
[Prior art]
Conventionally, a semiconductor device such as a semiconductor package or an optical communication module (optical semiconductor module) is provided with a heat radiating member called a heat sink to efficiently dissipate heat generated in the semiconductor package or optical semiconductor module outside the system. (Heat is exhausted). Such a heat sink has high thermal conductivity and good thermal conductivity, and since it is bonded to a ceramic substrate or glass substrate, the thermal expansion coefficient is the thermal expansion coefficient of ceramic or glass (4 to 4). 10 ppm / K) is required. At present, a tungsten-copper (WCu) alloy is used as a material having both the opposite characteristics of thermal conductivity and thermal expansion coefficient.
[0003]
As a heat sink made of such a tungsten-copper (WCu) alloy, an infiltrated sintered alloy in which copper (Cu) is infiltrated (impregnated) into the pores of a sintered body made of tungsten (W). A heat sink is used. By the way, the heat sink which consists of such an infiltration sintered alloy is manufactured in the following procedures, for example. First, a tungsten (W) powder is preliminarily blended with an organic binder to form a raw material mixture, and this raw material mixture is pressed by a mold press to form a thin plate-shaped molded body. The molded body is degreased and sintered to form a porous sintered body, and copper (Cu) is infiltrated (impregnated) into the pores of the sintered body. Thereafter, a method is generally employed in which the surface of the infiltrated sintered body is subjected to surface processing using a milling machine, a lapping machine or the like, and finally used as a heat sink.
[0004]
[Problems to be solved by the invention]
However, a heat sink made of such an infiltrated sintered alloy sinters a molded body pressed by a die press, and thus it is difficult to produce a complicated shape. For this reason, when manufacturing a heat sink having a complicated shape, it is necessary to subject the infiltration sintered alloy to secondary processing such as cutting. However, since the infiltrated sintered alloy is a difficult-to-process material, it is not easy to perform the cutting process, resulting in problems that the cost of the cutting process is high and the productivity is poor.
[0005]
Further, since the sintered body of tungsten powder is a sponge-like structure, the size and the density of the holes constituting the structure are not uniform. For this reason, the filling density of the copper infiltrated into the pores becomes non-uniform, and the thermal expansion coefficient and the thermal conductivity vary depending on the part. As a result, the heat sink made of such an infiltrated sintered body has a problem that its thermal characteristics are not stable and it is not reliable. The sintered body infiltrated with copper is thermally conductive along the portion where copper is present. However, if the filling density of copper is not uniform, the direction of heat conduction is random. For this reason, it has become difficult to quickly dissipate the generated heat to the outside of the system, resulting in a problem that heat dissipation efficiency is reduced.
[0006]
Further, in order to increase the sintered density of the sintered body, a sintering aid such as nickel (Ni) that is solid-solved with tungsten may be added. However, when the sintering aid is added, the sintered density is improved, but the crystal grains of tungsten grow, causing a problem that the heat conduction path is cut off and the thermal conductivity is lowered. In addition, when the tungsten crystal grains grow, the surface roughness of the infiltrated sintered body becomes rough, so surface polishing (secondary processing) using a lapping machine or the like is performed to smooth the surface of the sintered body. The process to make is necessary. For this reason, the manufacturing process of the heat sink becomes complicated, resulting in a problem that the manufacturing cost increases.
[0007]
Furthermore, when there is a portion in which copper is not infiltrated (impregnated) in the pores of the sintered body, pinholes are easily generated on the surface of the sintered body, and a plating layer is formed on the pinholes. In such a case, plating blisters are likely to occur, resulting in problems that it is difficult to obtain a high-quality heat sink with good plating properties. In addition, after copper is infiltrated (impregnated), a large amount of surplus infiltrant (copper) adheres to the surface of the sintered body. Later, it was necessary to carry out a surface polishing process, and there was a problem that the number of man-hours for finishing the heat sink increased and the manufacturing cost further increased.
[0008]
Accordingly, the present invention has been made to solve the above-described problems, and is easily manufactured, has a low thermal expansion coefficient, and has a high heat dissipation tungsten-copper (WCu) alloy sintered body or molybdenum-copper. It consists of a sintered body of (MoCu) alloy Semiconductor carrier and manufacturing method thereof The purpose is to provide.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a semiconductor carrier including a carrier base having a mount portion on which a semiconductor element is mounted, wherein the carrier base having the mount portion is W-Cu composite metal powder or W powder and Cu powder. Of a WCu alloy sintered body, or a Mo-Cu composite metal powder or a mixed metal powder of Mo powder and Cu powder, which is integrally formed in a three-step step shape by injection molding of the mixed metal powder with It consists of a sintered body of a MoCu alloy of a molded body that is integrally molded so as to have a three-step staircase shape by injection molding, and the average grain size of W and Mo crystal grains constituting these sintered bodies is 3 μm. Below, the ratio of Cu which comprises a sintered compact is 5 wt% or more and 30 wt% or less with respect to the mass of this sintered compact At the same time, the three stages are a first stage that is a flat plate-shaped mounting portion having a rectangular planar shape, a second stage that is a cylindrical cap fixing part that fixes the cap, and a smaller diameter than the second stage. It is formed in a columnar shape and comprises a third stage serving as a terminal portion for fixing a plurality of leads. It is characterized by that.
[0010]
Here, in the WCu alloy or the MoCu alloy, the thermal conductivity increases as the Cu ratio increases, but the thermal expansion coefficient also increases. This is because Cu is a metal excellent in heat conduction, and as the proportion of Cu increases, the coefficient of thermal expansion increases. For this reason, in order to obtain a WCu alloy or MoCu alloy having a low thermal expansion coefficient, it is necessary to regulate the ratio of Cu. In general, if the coefficient of thermal expansion is 10 ppm / K or less, it can be said that the coefficient of thermal expansion is sufficiently low. Therefore, the Cu content ratio of the WCu alloy or MoCu alloy is 30 wt.% With respect to the mass of the WCu alloy or MoCu alloy. % Can be said to be desirable.
[0011]
On the other hand, in the WCu alloy or the MoCu alloy, it has been found that the thermal conductivity improves as the average grain size of the W or Mo crystal grains decreases. Generally, if the thermal conductivity is 170 W / m · K or more, it can be said that the thermal conductivity is high. In the case where the average grain size of W or Mo crystal grains is 3 μm, the thermal expansion coefficient is 5.5 ppm / K when the thermal conductivity is 170 W / m · K, and the ratio of Cu at this time is the firing ratio. The result of 5 wt% was obtained with respect to the mass of the bonded body.
From this, in the sintered body of WCu alloy or MoCu alloy, the average grain size of W or Mo crystal grains is 3 μm or less, and the ratio of Cu is 5 wt% or more and 30 wt% with respect to the mass of the sintered body. It can be said that it is preferable to use the following.
[0012]
In this case, the sintered body is a sintered body of a molded body formed by injection molding of W-Cu composite metal powder or a mixed metal powder of W powder and Cu powder, or Mo-Cu composite metal powder or Mo powder and Cu. If the sintered body of the molded body formed by injection molding of mixed metal powder with powder, a heat sink with a complicated shape can be obtained easily and easily without subjecting this type of sintered body to secondary processing. This is desirable.
Then, such a heat sink is provided with a semiconductor carrier having a carrier base having a mount portion for mounting a semiconductor element. To ya When applied, the heat generated in the semiconductor element can be quickly released (exhaust heat) out of the system.
[0013]
Since the light output conversion efficiency of the semiconductor laser is usually 20 to 50%, more than half of the electric power supplied to the semiconductor laser is consumed as heat. In general, when the temperature of the semiconductor carrier exceeds 45 ° C., the oscillation output of the semiconductor laser decreases even when a voltage higher than that is applied. Therefore, when a semiconductor laser is mounted on the semiconductor carrier as described above, the heat generated by the semiconductor laser can be quickly emitted out of the system. For this reason, it becomes possible to increase the oscillation output of the semiconductor laser until the temperature of the semiconductor carrier reaches 45 ° C.
[0014]
Such a semiconductor laser is preferably a 980 nm band semiconductor laser or a 1480 nm band semiconductor laser. When a 980 nm band semiconductor laser is mounted on a semiconductor carrier, the semiconductor carrier reaches a temperature of 45 ° C. in a heat sink made of a sintered body having an average grain size of W or Mo of the semiconductor carrier of 3 μm. The laser oscillation output was 120 mW. From this, it can be said that the semiconductor element is preferably a semiconductor laser having an oscillation wavelength of 980 nm and an oscillation output of 120 mW or less.
[0015]
On the other hand, when a 1480 nm band semiconductor laser is mounted on a semiconductor carrier, in a heat sink composed of a sintered body having an average grain size of W or Mo of the semiconductor carrier of 3 μm, the semiconductor carrier temperature reaches 45 ° C. The laser oscillation output is 90mW Met. Therefore, the semiconductor device is a semiconductor laser with an oscillation wavelength of 1480 nm, and the oscillation output is 90mW It can be said that the following semiconductor laser is preferable.
When a semiconductor laser is mounted on the above-described semiconductor carrier, it is necessary to arrange the semiconductor laser at an accurate position and efficiently couple the laser light to the optical fiber. For this reason, it is desirable that the mount portion of the semiconductor carrier is smoothed (mirrored) by secondary processing.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Next, the present invention Half of An example in which the embodiment of the conductor carrier is applied to a semiconductor carrier used in an optical semiconductor module will be described with reference to FIG. FIG. 1 is a perspective view schematically showing an example in which the semiconductor carrier of the present invention is applied to a semiconductor carrier used in a stem type optical semiconductor module.
[0017]
1. Semiconductor carrier (heat sink)
A semiconductor carrier 10 in FIG. 1 includes a carrier base 11 having a mount portion 15 on which a semiconductor laser is mounted. The carrier base 11 and the mount portion 15 are integrally formed of a sintered body. Here, the carrier base 11 is formed in a three-step staircase shape, the flat shape forming the bottom portion in the first step is a rectangular and flat plate-shaped mounting portion 12, and a cap described later in the second step (FIG. 8). A cylindrical cap fixing portion 13 for fixing the reference), and a terminal portion 14 having a plurality of leads fixed at the third stage and formed in a cylindrical shape having a smaller diameter than the second stage. Further, the mount portion 15 is located at the upper portion of the carrier base 11 and is formed in a hexagonal column shape, and the surface of one side wall thereof is planarized.
[0018]
The semiconductor carrier 10 configured as described above has a function of a heat sink, and is formed of a sintered body formed into a shape as shown in FIG. The sintered body having such a heat sink function is a WCu alloy sintered body or a MoCu alloy sintered body. In this case, in the sintered body of the WCu alloy, the average grain size of the W crystal grains is 3 μm or less, and the Cu content ratio is 5 wt% or more and 30 wt% or less with respect to the mass of the sintered body. Is. In the sintered body of the MoCu alloy, the average grain size of the Mo crystal grains is 3 μm or less, and the Cu content is 5 wt% or more and 30 wt% or less with respect to the mass of the sintered body. It is.
[0019]
Here, in the sintered body of the WCu alloy or the sintered body of the MoCu alloy, the average grain size of the W crystal grains or the Mo crystal grains is 3 μm or less, and the Cu content is based on the mass of the sintered body. The reason for using 5 wt% or more and 30 wt% or less is that, even if the thermal expansion coefficient is the same, the smaller the grain size of the W crystal grains or the Mo crystal grains, the higher the thermal conductivity. This is because it was obtained. This will be described based on the following experimental results. FIG. 2 shows the coefficient of thermal expansion (ppm / K) and thermal conductivity (W / m · K) when the average grain size of W crystal grains and the Cu content ratio of the sintered body of the WCu alloy are changed. The result of having obtained the relationship is shown.
[0020]
In FIG. 2, curve a shows the result when the average grain size of the W crystal grains is 3 μm, and curve b shows the result when the average grain size of the W crystal grains is 5 μm, Curve c shows the result when the average grain size of the W crystal grains is 7 μm, and curve d shows the result when the average grain size of the W crystal grains is 10 μm. Also. In FIG. 2, 95W5Cu means a WCu alloy in which the mass ratio of W is 95 wt% and the mass ratio of Cu is 5 wt%. The same applies to 90W10Cu, 85W15Cu, 80W20Cu, 75W25Cu, 70W30Cu, and 65W35Cu.
[0021]
As is apparent from the results of FIG. 2, it can be seen that the thermal conductivity increases as the Cu content ratio of the WCu alloy increases, but the thermal expansion coefficient also increases. This is because Cu is a metal excellent in heat conduction, so that the coefficient of thermal expansion increases as the content ratio of Cu increases. For this reason, in order to obtain a WCu alloy having a low thermal expansion coefficient, it is necessary to regulate the Cu content ratio. In general, it can be said that the coefficient of thermal expansion is sufficiently low when the coefficient of thermal expansion is 10 ppm / K or less. Moreover, when the content ratio of Cu in the WCu alloy is more than 30 wt%, the skeleton volume of W grains decreases, Cu cannot be retained so that a coarse sponge cannot retain water, and Cu freezes on the surface ( The shape will collapse and the thermal properties cannot be improved. For this reason, it can be said that it is desirable for the content rate of Cu of a WCu alloy to be 30 wt% or less with respect to the mass of a WCu alloy (sintered body).
[0022]
On the other hand, as the average grain size of the W crystal grains decreases from 10 μm to 3 μm, the curve in FIG. 2 moves upward, so that the thermal conductivity improves as the average grain size of the W crystal grains decreases. I understand. From this, it can be said that it is preferable to use a W crystal grain having a small average grain size. Generally, if the thermal conductivity is 170 W / m · K or more, it can be said that the thermal conductivity is high. The thermal expansion coefficient when the thermal conductivity is 170 W / m · K is 5.5 ppm / K when the average grain size of W crystal grains is 3 μm, and when the average grain size is 5 μm. When the average particle size is 7 μm, it is 6.3 ppm / K, and when the average particle size is 10 μm, it is 6.6 ppm / K.
For this reason, in the sintered body of the WCu alloy, a W crystal grain having an average grain size of 3 μm or less and a Cu ratio of 5 wt% to 30 wt% with respect to the mass of the sintered body is used. It can be said that it is preferable.
[0023]
FIG. 3 shows the coefficient of thermal expansion (ppm / K) and thermal conductivity (W / m · W) when the average grain size of Mo crystal grains and the mass ratio of Cu in the sintered body of the MoCu alloy are changed. The result of having obtained | required the relationship of K) is shown. In FIG. 3, curve e shows the result when the average grain size of the Mo crystal grains is 3 μm, and curve f shows the result when the average grain size of the Mo crystal grains is 5 μm, The curve g shows the result when the average grain size of Mo crystal grains is 7 μm, and the curve h shows the result when the average grain size of Mo crystal grains is 10 μm. In FIG. 3, the same result as that of the sintered body of the WCu alloy in FIG. 2 was obtained. From this, the MoCu alloy sintered body having an average grain size of Mo of 3 μm or less and a Cu content ratio of 5 wt% to 30 wt% with respect to the mass of the sintered body is used. Is preferable.
[0024]
FIG. 4 is a diagram showing the relationship between the grain size of W crystal grains and the frequency when the average grain size of W crystal grains is 3 μm in the sintered body of the WCu alloy, and FIG. In the sintered body of a WCu alloy, it is the figure which calculated | required the relationship between the particle size of the W crystal grain, and the frequency in case the average particle diameter of the W crystal grain is 10 micrometers. As is clear from FIG. 4, it can be seen that the distribution is a normal distribution that peaks when the grain size of the W crystal grains is 3 μm. Further, as is apparent from FIG. 5, it can be seen that the distribution is a normal distribution that peaks when the grain size of the W crystal grains is 10 μm.
[0025]
2. Fabrication of semiconductor carrier
Next, a manufacturing procedure of the semiconductor carrier (heat sink) 10 having the above-described configuration will be described in detail below with reference to FIGS. 6 is a perspective view showing a green body to be a semiconductor carrier formed by injection molding of a composite metal powder, and FIG. 7 is a perspective view showing a semiconductor carrier formed by sintering the green body of FIG. It is.
[0026]
First, a W—Cu composite metal powder having an average particle diameter of 1 μm adjusted so that the W content is 95 to 70 mass% and the Cu content is 5 to 30 mass% was prepared. Thereafter, this W—Cu composite metal powder was put into a jet mill. At this time, the pressure of the jet mill was set to 3 to 10 bar, and the rotational speed of the jet mill was set to 5000 rpm. In this state, the jet mill was rotated for 20 minutes so that the W-Cu composite metal powders were not aggregated together, and the W-Cu composite metal powders were refined and spheroidized. Thereby, a W—Cu composite metal powder having an average particle size of 0.1 to 0.3 μm was obtained.
[0027]
Here, the W-Cu composite metal powder is manufactured from a predetermined amount of tungsten oxide and a predetermined amount of copper oxide. The For example, those produced by the production methods disclosed in JP-A-8-239219 and JP-A-8-333119 can be used. As the tungsten oxide, ammonium paratungstate (APT) or ammonium metatungstate (AMT) is preferable. Moreover, as a copper oxide, cuprous oxide, cupric oxide, or copper hydroxide is preferable. Then, either ammonium paratungstate (APT) or ammonium metatungstate (AMT) and any one of cuprous oxide, cupric oxide or copper hydroxide are mixed at an appropriate mass ratio to form a mixed powder. Then, cupric tungstate (CuWO), which is a tungsten-copper composite oxide formed by dehydration from this mixed powder. _Four ) / Tungsten trioxide (WO _Three ) Is desirable.
[0028]
Note that a mixed metal powder of W powder and Cu powder may be used instead of the W-Cu composite metal powder. Also in this case, it is necessary to adjust so that the ratio of W is 95 to 70 mass% and the ratio of Cu is 5 to 30 mass%.
Further, instead of using a jet mill, a W-Cu composite metal powder or a mixed metal powder of W powder and Cu powder may be pulverized using a ball mill. In this case, it is necessary to rotate the ball mill at a rotational speed of 50 rpm for 20 to 200 hours to pulverize the composite metal powder or the mixed metal powder until the average particle size becomes 0.1 to 0.3 μm.
[0029]
Next, 55-50 vol% of a binder is added to 45-50 vol% of the W-Cu composite metal powder having an average particle size of 0.1-0.3 [mu] m thus obtained, and mixed and kneaded. A molding composition was obtained. In addition, as a binder, what added waxes, such as paraffin wax, a carnapa wax, a beeswax, to organic resin, such as a polypropylene (PP), a polystyrene (PS), polyethylene (PE), an acryl, and a POM resin, is used. It is desirable to use it.
[0030]
Subsequently, the obtained molding composition was pelletized with a pelletizer. This was put into a hopper of an injection molding machine having a mold clamping pressure of 20 t, and injection molded into a mold having an injection temperature of 160 ° C. and a mold temperature of 25 ° C. Thereafter, the mold was cooled with water to solidify the injection, and a green body (molded body) 10A to be the semiconductor carrier 10 was obtained. FIG. 6 shows the green body 10A thus obtained. The green body 10A includes a carrier base 11A having a mount portion 15A, and the carrier base 11A and the mount portion 15A are integrally formed.
[0031]
The carrier base 11A is formed in a three-step staircase shape. A flat plate-shaped mounting portion 12A that forms a bottom portion in the first step, a cylindrical cap fixing portion 13A that fixes a cap in the second step, and a plurality of leads fixed in the third step by fixing a plurality of leads. It consists of a cylindrical terminal portion 14A having a diameter smaller than two stages. And attachment opening 12a-1, 12a-1 is formed in the both ends of attachment part 12A. The terminal portion 14A is formed with a plurality of through holes 14a-1 for inserting leads, while the mount portion 15A is located in the upper part of the carrier base 11A and is formed in a hexagonal column shape.
[0032]
Next, the green body 10A was placed in a binder removal apparatus (not shown). Thereafter, nitrogen gas was introduced into the binder removal apparatus at a flow rate of 1 liter / min to create a nitrogen atmosphere. And the temperature increase rate heated at 0.1 degree-C / min, the temperature of 550 degreeC was hold | maintained for 2 hours, and 10 A of green bodies were debinder processed. By the binder removal process, the above-described binder is volatilized (removed) to obtain a brown body made of W and Cu. Then, it cooled to room temperature and took out the brown body from the binder removal apparatus.
[0033]
Next, the obtained brown body was placed in a deoxygenation device (not shown). Thereafter, hydrogen gas at a flow rate of 1 to 10 liters / minute is flown into the deoxygenation device, and the brown body is sufficiently placed in a hydrogen gas stream in a temperature environment of 500 ° C. to 1000 ° C. below the melting point temperature of copper. The brown body was deoxygenated by exposure. By this deoxygenation treatment, the oxide layer on the surface of the tungsten particles constituting the brown body is sufficiently reduced, and the wettability with copper is improved.
[0034]
Subsequently, the deoxygenated brown body was put into a sintering furnace, and heated in a hydrogen stream at a heating rate of 5 ° C./1 hour until the following sintering temperature was reached. Thereafter, the sintering was performed by maintaining this sintering temperature for 2 hours. As a result, the green body 10A contracted and became smaller, and a semiconductor carrier 10 made of a sintered body of a WCu alloy as shown in FIG. 7 was produced. In the semiconductor carrier 10 thus manufactured, tungsten crystal grains grow greatly during sintering. However, in the present invention, since the sintering temperature is adjusted as follows, the growth of tungsten crystal grains can be suppressed.
[0035]
Specifically, when the W-Cu composite metal powder adjusted so that the ratio of Cu is 5% by mass with respect to the mass of the composite metal powder is used, the temperature environment is set to 1275 to 1325 ° C. Sintering was performed. Similarly, when the ratio of Cu is 10% by mass, it is 1225 to 1275 ° C., when the ratio of Cu is 15% by mass, it is 1175 to 1225 ° C., and when the ratio of Cu is 20% by mass, it is 1150 to 1200 ° C. When the ratio of Cu was 30% by mass, sintering was performed at 1125 to 1175 ° C., respectively. The average grain size of the tungsten crystal grains of the obtained semiconductor carrier 10 was measured and found to be 3 μm or less.
[0036]
The semiconductor carrier 10 contracts and becomes smaller than the green body 10A due to this sintering, but the configuration including the carrier base 11 formed in a three-step staircase shape having the mount portion 15 is the same. The carrier base 11 includes a flat plate-shaped mounting portion 12 that forms a bottom portion at the first step, a cylindrical cap fixing portion 13 that fixes a cap at the second step, and a plurality of third portions at the third step. And a cylindrical terminal portion 14 having a diameter smaller than that of the second stage. Mounting openings 12a and 12a are formed at both ends of the mounting portion 12, and the terminal portion 14 is formed with a plurality of through holes 14a for inserting leads. On the other hand, the mount portion 15 is located in the upper part of the carrier base 11 and is formed in a hexagonal column shape.
[0037]
3. Optical semiconductor module using semiconductor carrier
Next, a manufacturing procedure of the optical semiconductor module 20 using the semiconductor carrier (heat sink) 10 manufactured as described above will be described in detail below with reference to FIGS. 8 is a perspective view showing an optical semiconductor module formed by mounting a semiconductor laser or the like on the semiconductor carrier 10 of FIG. 7, and FIG. 9 is a cap (cover) attached to the optical semiconductor module of FIG. It is a perspective view which shows the optical semiconductor module of a state.
[0038]
First, by using the semiconductor carrier 10 manufactured as described above, one side surface portion of the mounting portion 15 of the semiconductor carrier 10 is machined to have a surface roughness TIR (maximum height) of 3 μm at maximum, Ra ( Polishing was smoothly performed so that the average roughness was 0.5 μm or less. Thereafter, processing burrs were removed by a blasting machine, mirror finishing was performed, and secondary processing was performed. Thereafter, the semiconductor laser 21 was placed and fixed so that the laser was emitted upward on the smooth surface. A light receiving element 22 for monitoring and controlling the output of the laser was placed and fixed on the smooth surface below the semiconductor laser 21.
[0039]
Further, a plurality of lead wires 23, 23, 23 and a ground wire 24 were inserted into the plurality of through holes 14 a for inserting leads of the carrier base 11. Thereafter, the glass sealing agent 25 was filled in the through holes 14a, and the lead wires 23, 23, 23 and the ground wire 24 were fixed in the respective through holes 14a. The upper portions of the plurality of lead wires 23, 23, 23 extend to the upper surface of the terminal portion 14 of the carrier base 11, and this extended portion is used for connection with the semiconductor laser 21, the light receiving element 22, and the like. It becomes a terminal.
[0040]
On the other hand, a cap 26 for holding the semiconductor laser 21 and the light receiving element 22 in an airtight manner was prepared, and this cap 26 was placed on the cap fixing portion 13 of the carrier base 11. After this, the inner peripheral surface of the lower end of the cap 26 is Terminal part 14 Stuck to the peripheral wall. In this case, the inner peripheral surface of the lower end of the cap 26 and Terminal part 14 A brazing material (for example, silver wax) is interposed between the peripheral wall and a jig made of carbon or alumina. Next, this jig was replaced with 40% hydrogen (H ₂ ) Containing nitrogen (N ₂ ) In a reflow furnace in a gas atmosphere, the cap is placed on a belt with a moving speed of 30 mm / min and heat-treated under reflow conditions (temperature rise profile) that is heated at a maximum temperature of 900 ° C. for 20 minutes. 26 on the inner peripheral surface of the lower end Terminal part 14 Stuck to the peripheral wall.
[0041]
Next, the optical semiconductor module 20 is manufactured by filling the cap 26 with nitrogen gas and making the cap 26 atmosphere of nitrogen gas. An optical fiber 27 is attached to the tip of the cap 26, and a lens (not shown) is accommodated so that laser light can be efficiently incident on the optical fiber 27.
In the optical semiconductor module 20 using the semiconductor carrier 10 configured as described above, the laser light emitted upward from the semiconductor laser 21 is efficiently coupled to the optical fiber 27 by the lens. In addition, since the optical semiconductor module 20 has a structure that does not have a cooling means such as a Peltier element, the semiconductor carrier 10 is required to have a heat dissipation property.
[0042]
This is because the light output conversion efficiency of the semiconductor laser 21 is normally 20 to 50%. That is, more than half of the electric power supplied to the semiconductor laser 21 is consumed as heat. In general, when the temperature of the semiconductor carrier 10 exceeds 45 ° C., the laser output decreases even when a voltage higher than that is applied.
Therefore, as the semiconductor laser 21, an optical semiconductor module 20 (A, B) on which a 980 nm band semiconductor laser and a 1480 nm band semiconductor laser are mounted is configured. As the semiconductor carrier 10 used for each of these optical semiconductor modules 20 (A, B), each optical semiconductor module 20 (A1, A2, A3, A4, B1, B2) is used by using a sintered body changed as follows. , B3, B4).
[0043]
That is, the W-Cu composite metal powder adjusted so that the Cu content ratio is 15% by mass with respect to the mass of the composite metal powder is used and sintered so that the average grain size of the W crystal grains becomes 3 μm. The optical semiconductor module 20 using the semiconductor carrier 10 made of the sintered body was designated as A1 and B1. Also, an optical semiconductor module 20 using a composite metal powder having the same Cu content ratio and having an average grain diameter of W of 5 μm as A2 and B2, and an optical semiconductor module using 7 μm. 20 is A3 and B3, and the optical semiconductor module 20 using 10 μm is A4 and B4.
[0044]
Next, by changing the applied voltage to each semiconductor laser of each optical semiconductor module 20 (A1, A2, A3, A4, B1, B2, B3, B4), oscillation output (laser output) (mW) of each semiconductor laser When the relationship of the temperature (° C.) of the semiconductor carrier 10 with respect to is obtained, the results shown in FIGS. 10 and 11 were obtained. 10 shows a case where a 980 nm band semiconductor laser is mounted, and FIG. 11 shows a case where a 1480 nm band semiconductor laser is mounted.
As is apparent from the results of FIGS. 10 and 11, the temperature of the semiconductor carrier 10 increases as the laser output increases, regardless of whether the semiconductor laser is in the 980 nm band or the 1480 nm band. I understand. This is because the amount of heat generated increases as the laser output increases.
[0045]
By the way, in FIG. 10, in the optical semiconductor module A4 (with an average grain size of W crystal grains of the semiconductor carrier 10 of 10 μm), the laser output at which the temperature of the semiconductor carrier 10 reaches 45 ° C. is 50 mW. In A3 (the average grain size of the W crystal grains of the semiconductor carrier 10 is 7 μm), the laser output at which the temperature of the semiconductor carrier 10 reaches 45 ° C. is 70 mW, and the optical semiconductor module A2 (the W crystal of the semiconductor carrier 10) In the case where the average particle size of the grains is 5 μm), the laser output at which the temperature of the semiconductor carrier 10 reaches 45 ° C. is 100 mW, and the optical semiconductor module A1 (the average grain size of the W crystal grains of the semiconductor carrier 10 is 3 μm) ), The laser output at which the temperature of the semiconductor carrier 10 reaches 45 ° C. is 120 mW. It can be seen that.
[0046]
On the other hand, in FIG. 11, in the optical semiconductor module B4 (the average grain size of W crystal grains of the semiconductor carrier 10 is 10 μm), the laser output at which the temperature of the semiconductor carrier 10 reaches 45 ° C. is 40 mW, and the optical semiconductor module In B3 (the average grain size of the W crystal grains of the semiconductor carrier 10 is 7 μm), the laser output at which the temperature of the semiconductor carrier 10 reaches 45 ° C. is 58 mW, and the optical semiconductor module B2 (the W crystal of the semiconductor carrier 10) In the case where the average particle size of the grains is 5 μm), the laser output at which the temperature of the semiconductor carrier 10 reaches 45 ° C. is 75 mW, and the optical semiconductor module B1 (the average grain size of the W crystal grains of the semiconductor carrier 10 is 3 μm) ), The laser output at which the temperature of the semiconductor carrier 10 reaches 45 ° C. is 90 mW. Door can be seen.
[0047]
From these facts, when the semiconductor carrier 10 having an average grain size of W of WCu alloy of 3 μm is used, if a semiconductor laser of 980 nm band is mounted on the semiconductor carrier 10, the maximum output of the semiconductor laser is 120 mW. . If a 1480 nm band semiconductor laser is mounted on the semiconductor carrier 10, the maximum output of the semiconductor laser is 90mW It becomes. Thus, when the semiconductor carrier 10 of the present invention is used, the maximum output of the semiconductor laser can be increased. If the light output conversion efficiency of the laser increases, a higher output laser can be mounted.
[0048]
4). Modified example of optical semiconductor module mounting structure
In the optical semiconductor module 20 described above, the mounting portion 12 is provided at a position perpendicular to the emitting direction of the semiconductor laser. For this reason, in order to emit laser light in the horizontal direction, mounting openings 12a and 12a formed at both ends of the mounting portion 12 using an angle with an L-shaped cross section as a separate member, It is necessary to insert the bolt into the mounting opening formed at the angle of the member, and screw the nut into the bolt to attach the optical semiconductor module 20 to the angle of the other member. Therefore, an attachment structure that can emit laser light in a horizontal direction without using an angle of a separate member was studied. As a result, the following various modifications could be obtained.
[0049]
(1) First modification
In the first modification, instead of the flat plate-like mounting portion 12 described above, as shown in FIG. 12 (a), a flat plate-like carrier holding portion 28a and a mounting vertically falling from the carrier holding portion 28a. The fixing part 28 composed of the part 28b is used. And this fixing | fixed part 28 is arrange | positioned under the cylindrical cap fixing | fixed part 13. FIG. The attachment portion 28b is provided with attachment openings 28c and 28c. By providing such a fixing portion 28, it is possible to emit laser light from the optical semiconductor module 20 in the horizontal direction by fixing the attachment portion 28b to a horizontal plane without using an angle of another member.
[0050]
(2) Second modification
In the second modification, instead of the above-described flat mounting portion 12, as shown in FIG. 12 (b), a flat carrier holding portion 29a and the carrier holding portion 29a stand vertically from both sides. A fixing portion 29 having lowering attachment portions 29b and 29b is used. And this fixing | fixed part 29 is arrange | positioned under the cylindrical cap fixing | fixed part 13. FIG. Each attachment portion 29b is provided with an attachment opening 29c. By providing such a fixing portion 29, it is possible to emit laser light from the optical semiconductor module 20 in the horizontal direction by fixing the attachment portion 29b to a horizontal plane without using an angle of another member. In this case, since the material of the attachment parts 29b and 29b can be reduced rather than the attachment part 28b of the 1st modification mentioned above, this kind of fixing | fixed part 29 can be reduced in weight.
[0051]
(3) Third modification
In the third modified example, instead of the flat plate-shaped mounting portion 12 described above, as shown in FIG. 12C, a flat plate-shaped carrier holding portion 30a and a mounting that vertically falls from the carrier holding portion 30a. The fixing part 30 provided with the part 30b is used. And this fixing | fixed part 30 is arrange | positioned under the cylindrical cap fixing | fixed part 13. FIG. Note that mounting grooves 30c and 30c are provided in the mounting portion 30b. By providing such a fixing portion 30, the laser beam can be emitted from the optical semiconductor module 20 in the horizontal direction by fixing the attachment portion 30 b to a horizontal plane without using an angle of another member. In this case, since the material of the attachment portion 30b can be reduced as in the second modification described above, this type of fixing portion 30 can be reduced in weight.
[0052]
(4) Fourth modification
In the fourth modification, instead of the flat plate-like mounting portion 12 described above, as shown in FIG. 13A, a flat plate-like carrier holding portion 31a and a mounting portion that rises vertically from the carrier holding portion 31a. A fixing portion 31 made of 31b is used. And this fixing | fixed part 31 is arrange | positioned under the cylindrical cap fixing | fixed part 13. FIG. The attachment portion 31b is provided with attachment openings 31c and 31c. Thereby, if the attachment part 31b is fixed to a horizontal plane, the laser light can be emitted from the optical semiconductor module 20 in the horizontal direction. In this case, by making the length of the attachment portion 31b longer than the length of the carrier holding portion 31a, the attachment to the fixed portion is facilitated, and the attachment portion 31b stands vertically from the carrier holding portion 31a. When the fixing portion 31 is attached to the fixed portion, the lead wires 23, 23, 23 and the ground wire 24 do not get in the way and can be easily attached.
[0053]
(5) Fifth modification
In the fifth modification, instead of the above-described flat mounting portion 12, as shown in FIG. 13 (b), a flat carrier holding portion 32a and the carrier as shown in FIG. 13 (a). A fixing portion 32 including an attachment portion 32b that rises vertically from the holding portion 32a is used. And this fixing | fixed part 32 is arrange | positioned under the cylindrical cap fixing | fixed part 13. FIG. The attachment portion 32b is provided with attachment openings 32c and 32c. Thereby, if the attachment part 32b is fixed to a horizontal plane, the laser light can be emitted from the optical semiconductor module 20 in the horizontal direction. In this case, since the material of the attachment part 32b can be reduced by making the length of the attachment part 31b equal to the length of the carrier holding part 31a, this type of fixing part 32 can be reduced in weight. Similarly to the fixing portion 31, the attachment portion 32b stands vertically from the carrier holding portion 32a. Therefore, when the fixing portion 32 is attached to the fixed portion, the lead wires 23, 23, 23 and the ground wire 24 are obstructive. Can be easily installed.
[0054]
(6) Sixth modification
In the sixth modified example, instead of the above-described flat mounting portion 12, as shown in FIG. 13C, the flat carrier holding portion 33a and the carrier holding portion 33a rise vertically from both sides. The fixing part 33 provided with the attaching parts 33b, 33b is used. And this fixing | fixed part 33 is arrange | positioned under the cylindrical cap fixing | fixed part 33. FIG. The attachment portion 33b is provided with an attachment opening 33c. Thereby, if the attaching part 33b is fixed to a horizontal plane, the laser light can be emitted from the optical semiconductor module 20 in the horizontal direction. Moreover, since the material of the attachment parts 33b and 233 can be reduced rather than the attachment part 32b of the 5th modification mentioned above, this kind of fixing | fixed part 33 can be reduced in weight. Similarly to the fixing portion 32 of the fifth modified example, the attachment portion 33b rises vertically from the carrier holding portion 33a. Therefore, when the fixing portion 33 is attached to the fixed portion, the lead wires 23, 23, 23, The ground wire 24 does not get in the way and can be easily attached.
[0055]
(7) Seventh modification
In the seventh modified example, instead of the flat plate-like mounting portion 12 described above, as shown in FIG. 14A, a flat carrier-shaped carrier holding portion 34a and a vertical movement from the carrier holding portion 34a. A fixing portion 34 composed of a mounting portion 34b that falls is used. And this fixing | fixed part 34 is arrange | positioned under the cylindrical cap fixing | fixed part 13. FIG. Thereby, if the attachment part 34b is fixed to a horizontal surface, the laser light can be emitted from the optical semiconductor module 20 in the horizontal direction. In this case, it is formed in a square shape slightly larger than the diameter of the cap fixing portion 13 so as to reduce the area of the carrier holding portion 34a, but the attachment portion 34b is the same size as the first modification. Is formed. For this reason, the shape is slightly deformed so as to spread from the carrier holding portion 34a toward the mounting portion 34b. The attachment portion 34b is provided with attachment openings 34c, 34c. Thereby, since the material of the carrier holding part 34a can be reduced, this kind of fixing | fixed part 34 can be reduced in weight.
[0056]
(8) Eighth modification
In the eighth modified example, instead of the flat plate-like mounting portion 12 described above, as shown in FIG. 14B, a semicircular flat plate-like carrier holding portion 35a and a vertical direction from the carrier holding portion 35a. A fixing portion 35 including a mounting portion 35b that falls is used. And this fixing | fixed part 35 is arrange | positioned under the cylindrical cap fixing | fixed part 13. As shown in FIG. Thereby, if the attachment part 35b is fixed to a horizontal surface, the laser light can be emitted from the optical semiconductor module 20 in the horizontal direction. In this case, so as to reduce the area of the carrier holding portion 35a, it is formed in a semicircular shape slightly larger than the diameter of the cap fixing portion 13, but the mounting portion 35b has the same size as that of the first modification. It is formed to become. For this reason, it has a shape that widens from the carrier holding portion 35a toward the mounting portion 35b. Note that mounting openings 35c and 35c are provided in the mounting portion 35b. Thereby, since the material of the carrier holding part 35a can be reduced, this kind of fixing | fixed part 35 can be reduced in weight.
[0057]
(9) Ninth modification
In the ninth modified example, as shown in FIG. 15A, the cap fixing portion 13 is directly attached to the fixed portion without using the flat plate-like attachment portion 12 described above. In this case, a screw thread may be formed on the peripheral wall of the cap fixing portion 13 and directly screwed in the horizontal direction so as to be fixed to the fixed portion. Even if it fixes in this way, it becomes possible to emit a laser beam from the optical semiconductor module 20 in a horizontal direction without using an angle of another member.
[0058]
(10) Tenth modification
In the tenth modification, instead of the above-described flat mounting portion 12, as shown in FIG. 15 (b), a flat strip-shaped carrier holding portion 37a and a vertical standing from the carrier holding portion 37a. A fixing portion 37 composed of a lower mounting portion 37b is used. And this fixing | fixed part 37 is arrange | positioned under the cylindrical cap fixing | fixed part 13. FIG. Note that an attachment opening 37c is provided in the attachment portion 37b. Thereby, if the attachment part 37b is fixed to a horizontal surface, a laser beam can be emitted from the optical semiconductor module 20 in the horizontal direction. In this case, since the carrier holding portion 37a is formed in a strip shape and narrow in width, and the attachment portion 37b is also formed in the same width and narrow in width as the carrier holding portion 37a, the material of the fixing portion 37 is reduced. Therefore, this kind of fixing part 37 can be reduced in weight.
[0059]
(11) Eleventh modification
In the eleventh modified example, instead of the flat plate-like mounting portion 12 described above, as shown in FIG. 15 (c), a flat plate-like strip-shaped carrier holding portion 38a and a vertical stand from the carrier holding portion 38a. A fixing portion 38 composed of a mounting portion 38b that is lowered is used. And this fixing | fixed part 38 is arrange | positioned under the cylindrical cap fixing | fixed part 13. FIG. Note that an attachment opening 38c is provided in the attachment portion 38b. Thereby, if the attachment part 38b is fixed to a horizontal plane, the laser light can be emitted from the optical semiconductor module 20 in the horizontal direction. In this case, the carrier holding portion 38a is strip-shaped and narrow, but the attachment portion 38b is formed wider than the carrier holding portion 38a. For this reason, since the material of the fixing | fixed part 38 can be reduced although it becomes fewer than the fixing | fixed part 37, this kind of fixing | fixed part 38 can be reduced in weight.
[0060]
(12) Twelfth modification
In the twelfth modified example, instead of the flat plate-like mounting portion 12 described above, as shown in FIG. 16A, a flat plate-shaped carrier holding portion 40a and from both sides of the carrier holding portion 40a. A fixing portion 40 having mounting portions 40b and 40b that fall vertically is used, and the fixing portion 40 is disposed below the cylindrical cap fixing portion 13. Each attachment portion 40b, 40b is provided with an attachment opening 40c. As a result, the laser light can be emitted from the optical semiconductor module 20 in the horizontal direction by fixing the mounting portions 40b, 40b to a horizontal plane. In this case, it is formed in a square shape that is slightly larger than the diameter of the cap fixing portion 13 so as to reduce the area of the carrier holding portion 40a. For this reason, it has a shape that slightly expands from the carrier holding portion 40a toward the mounting portion 40b, and a constricted portion 40d is formed. Thereby, since the material of the carrier holding part 40a can be reduced, this kind of fixing | fixed part 40 can be reduced in weight.
[0061]
(13) Thirteenth modification
The thirteenth modification is substantially the same as the fixing part 40 of the twelfth modification described above, and, as shown in FIG. A fixing portion 41 provided with mounting portions 41b and 41b that vertically fall from both sides of the portion 41a is used, and the fixing portion 41 is disposed below the cylindrical cap fixing portion 13. Also in this case, the attachment portions 41b and 41b are provided with attachment openings 41c, respectively. In order to reduce the area of the carrier holding portion 41a, the carrier holding portion 41a is formed in a square shape slightly larger than the diameter of the cap fixing portion 13. For this reason, the carrier holding part 41a is directed toward the attachment part 41b. Dry It has a curled shape and a constricted portion 41d is formed. However, since stress may concentrate on the root portions of the mounting portions 41b and 41b and breakage may occur. In the thirteenth modification, the rib portions 41e are connected to the base portions of the mounting portions 41b and 41b. , 41b are formed integrally with each other so as to reinforce the strength of both mounting portions 41b, 41b.
[0062]
(14) Fourteenth modification
The fourteenth modified example is substantially the same as the fixing unit 40 of the twelfth modified example described above. As shown in FIG. 16C, the carrier holding part 42a that is slightly deformed in a flat plate shape and the carrier holding part A fixing portion 42 provided with mounting portions 42b, 42b that vertically fall from both sides of the portion 42a is used, and the fixing portion 42 is disposed below the cylindrical cap fixing portion 13. Also in this case, each of the attachment portions 42b and 42b is provided with an attachment opening 42c, and has a shape that slightly expands from the carrier holding portion 42a toward the attachment portion 42b, and a constricted portion 42d is formed. Yes. In the fourteenth modification, the strength of both attachment parts 42b and 42b is reinforced by forming an R part 42e integrally with the attachment parts 42b and 42b at the base part of both attachment parts 42b and 42b. Like to do.
[0063]
5. Package for semiconductor devices
In the example described above, the semiconductor carrier 10 and the stem type optical semiconductor module 20 using the semiconductor carrier (heat sink) 10 have been described. However, a semiconductor device package is formed using the heat sink of the present invention, and a DIP (Dual In-line Package: pin (lead wire) is arranged along the two long sides of the package using the semiconductor device package. Type optical semiconductor module can be manufactured. Hereinafter, a package for a semiconductor element used for manufacturing a DIP type optical semiconductor module will be described with reference to FIGS. 17 (a) and 17 (b). FIGS. 17A and 17B are perspective views schematically showing a package for a semiconductor element.
[0064]
As shown in FIG. 17A, the semiconductor element package 50 a of the present invention includes a frame member 51 and a lid member 55 that serves as a cover for the frame member 51. The frame member 51 has a substantially box shape and a substantially cylindrical window holder on one side wall. 52a , A base portion 53 serving as a bottom plate of the main body portion 52, and fixing portions 54, 54 that extend from other side walls of the main body portion 52 and fix the frame member 51 to the fixed member. It consists of. The main body portion 52, the base portion 53, and the fixing portions 54 and 54 are integrally formed by sintering.
[0065]
Further, as shown in FIG. 17B, the semiconductor element package 50 b of the present invention includes a frame member 56 and a lid member 55 serving as a cover for the frame member 56. The frame member 56 has a substantially box-shaped body portion 57 having a substantially cylindrical window holder 56a on one side wall, a base portion 58 serving as a bottom plate of the body portion 57, and other side walls of the body portion 57. And fixing portions 59 and 59 for fixing the frame member 56 to the fixed member. The main body portion 57, the base portion 58, and the fixing portions 59 and 59 are integrally formed by sintering.
[0066]
The base 53 (58) of the frame member 51 (56) is provided with a plurality of through holes for lead insertion (not shown), and a plurality of lead wires and grounding are provided in these through holes. After the wires are inserted, a glass sealant is filled in the through holes, and a plurality of lead wires and ground wires are fixed in each through hole by a hermetic seal. The upper portions of the plurality of lead wires extend to the upper surface of the terminal portion, and the extended portions serve as terminals for connection with a semiconductor laser, a light receiving element, and the like.
[0067]
And base part 53 (58) A semiconductor laser and an optical system (not shown) are arranged on the top, and a lid member 55 is joined on the frame member 51 (56) by seam welding to form a semiconductor element package 50a (50b). A semiconductor module will be formed. In the semiconductor element package 50a, a circular fixing hole 54a is formed in the fixing portion 54 as shown in FIG. On the other hand, in the package 50b for a semiconductor element, as shown in FIG. 17B, a semicircular fixing hole 59a that is semi-cut is formed in the fixing portion 59.
[0068]
Here, when the circular fixing hole 54a is provided in the fixing portion 54 as in the semiconductor element package 50a, the module can be attached to an accurate position when being attached to the substrate. On the other hand, when a semicircular fixing hole 59a having a semi-chip is provided in the fixing portion 59 as in the semiconductor element package 50b, the occurrence of welds during injection molding can be suppressed, and the product has defects such as cracks. No longer occurs.
[0069]
The frame member 51 (56) and the lid member 55 of the semiconductor element package 50a (50b) configured as described above are sintered with a WCu alloy or a MoCu alloy as in the case of the semiconductor carrier 10 described above. The body is desirable. In this case, in the sintered body of the WCu alloy, the average grain size of the W crystal grains is 3 μm or less, and the ratio of Cu is 5 wt% or more and 30 wt% or less with respect to the mass of the sintered body. Is desirable. Moreover, in the sintered body of the MoCu alloy, the average grain size of the Mo crystal grains is 3 μm or less, and the ratio of Cu is 5 wt% or more and 30 wt% or less with respect to the mass of the sintered body. desirable.
[0070]
Next, a method for manufacturing the frame member 51 (56) and the lid member 55 configured as described above will be described below. First, in the same manner as described above, after preparing a W-Cu composite metal powder having an average particle diameter of 1 μm adjusted so that the W ratio is 95 to 70 mass% and the Cu ratio is 5 to 30 mass%, This W—Cu composite metal powder was put into a jet mill to obtain a W—Cu composite metal powder having an average particle size of 0.1 to 0.3 μm. For the W-Cu composite metal powder 40 to 45 vol% thus obtained, organic resin such as binder (PP, PS, PE, acrylic, POM resin, paraffin wax, carnapa wax, beeswax is used. 60 to 55 vol% of the above-mentioned wax added), and mixed and kneaded to obtain a molding composition.
[0071]
Next, the obtained molding composition was pelletized by a pelletizer and then put into a hopper of an injection molding machine. The mold and lid for a frame member having an injection temperature of 160 ° C. and a mold temperature of 25 ° C. It was injection-molded in a member mold. Thereafter, these molds were water-cooled to solidify the injection, and a green body (molded body) to be the frame member 51 (56) and the lid member 55 was obtained. Next, after placing these green bodies in a binder removal apparatus (not shown), nitrogen gas was introduced at a flow rate of 1 liter / min to create a nitrogen atmosphere. And the temperature increase rate heated at 0.1 degree-C / min, the temperature of 550 degreeC was hold | maintained for 2 hours, and the green body was debinder-processed. By the binder removal process, the above-described binder is volatilized (removed) to obtain a brown body made of W and Cu. Then, it cooled to room temperature and took out the brown body from the binder removal apparatus.
[0072]
Next, after placing the obtained brown body in a deoxygenation device (not shown), hydrogen gas is allowed to flow into the deoxygenation device, and the brown body is placed in a temperature environment of 500 ° C. to 1000 ° C. below the melting point temperature of copper. The brown body was deoxygenated by sufficiently exposing it to a hydrogen gas stream. By this deoxygenation treatment, the oxide layer on the surface of the tungsten particles constituting the brown body is sufficiently reduced, and the wettability with copper is improved. Next, the deoxygenated brown body was placed in a sintering furnace and heated in a hydrogen stream until the following sintering temperature was reached. Thereafter, the sintering was performed by maintaining this sintering temperature for 2 hours. Thereby, a frame member 51 (56) and a lid member 55 made of a sintered body of a WCu alloy were produced. In the frame member 51 (56) and the lid member 55 thus manufactured, tungsten crystal grains grow greatly during sintering. However, in the present invention, since the sintering temperature is adjusted as follows, the growth of tungsten crystal grains can be suppressed.
[0073]
Specifically, when the W-Cu composite metal powder adjusted so that the ratio of Cu is 5% by mass with respect to the mass of the composite metal powder is used, the temperature environment is set to 1275 to 1325 ° C. Sintering was performed. Similarly, when the ratio of Cu is 10% by mass, it is 1225 to 1275 ° C., when the ratio of Cu is 15% by mass, it is 1175 to 1225 ° C., and when the ratio of Cu is 20% by mass, it is 1150 to 1200 ° C. When the ratio of Cu was 30% by mass, sintering was performed at 1125 to 1175 ° C., respectively. The average grain size of the tungsten crystal grains of the obtained semiconductor carrier 10 was measured and found to be 3 μm or less.
[0074]
In the semiconductor element package 50a (50b) described above, the frame member 51 (56) and the lid member 55 have been described as being composed of a WCu alloy or a MoCu alloy sintered body. Alternatively, it is not necessary to form a MoCu alloy sintered body, and at least the base portion 53 (58) of the frame member 51 (56) may be composed of a WCu alloy or MoCu alloy sintered body. In this case, the main body 52 (57) and the fixing portion 54 (59) or the lid member 55 of the frame member 51 (56) is made of Kovar (FeNiCo alloy) that approximates the thermal expansion coefficient with the WCu alloy or MoCu alloy. The base portion 53 (58) of WCu alloy or MoCu alloy may be integrally formed by sintering, or may be brazed with a brazing material such as AgCu.
[0075]
Further, a semiconductor element package is formed using the heat sink of the present invention, and a CAN type optical semiconductor module as shown in FIG. 18 can be manufactured using this semiconductor element package. This CAN type optical semiconductor module is an optical semiconductor module having a small base diameter. FIG. 18 is a perspective view schematically showing a CAN type optical semiconductor module. The CAN optical semiconductor module 60 of FIG. 18 includes a carrier base 61 having a mount portion 62 on which a semiconductor laser is mounted. The carrier base 61 and the mount 62 are integrally formed of a WCu alloy sintered body or a MoCu alloy sintered body similar to the above.
[0076]
Here, the carrier base 61 is formed in a disk shape, the mount portion 62 is positioned on the upper portion of the carrier base 61, and the surface of one side wall thereof is planarized. A semiconductor laser is fixed to the planar side wall so that the semiconductor laser is emitted upward, and a light receiving element for monitoring and controlling the output of the semiconductor laser is fixed to the lower part of the semiconductor laser. On the other hand, a cap 63 for holding the semiconductor laser and the light receiving element in an airtight manner is placed on the cap fixing portion of the mount portion 62, and the inner peripheral surface of the lower end portion of the cap 63 is fixed to the peripheral wall of the cap fixing portion. . Then, nitrogen gas is sealed in the cap 63, and the CAN type optical semiconductor module 60 is manufactured.
[0077]
A lens 64 is accommodated at the tip of the cap 63 so that laser light can be efficiently incident on the optical fiber. Further, a plurality of lead wires 65, 65, 65 are fixed to the carrier base 61 in a plurality of through holes for lead insertion. Since the CAN-type optical semiconductor carrier 60 configured as described above is not provided with an attachment portion, a holder is used as a separate member for emitting laser light in the horizontal direction, and the attachment formed on the holder of this separate member. The CAN optical semiconductor module 60 is inserted into the opening for attachment. The holder of the separate member is preferably formed of Fe or FeNi alloy.
[0078]
【The invention's effect】
As mentioned above , Ta The average grain size of the tungsten (W) or molybdenum (Mo) crystal grains constituting the sintered body composed of the Nungsten-copper (WCu) alloy or the molybdenum-copper (MoCu) alloy is 3 μm or less to constitute the sintered body. Since the content ratio of Cu is 5 wt% or more and 30 wt% or less with respect to the mass of the sintered body, it has a low thermal expansion coefficient and high heat dissipation. Semiconductor carrier (heat sink) It becomes possible to provide. In addition, such a low thermal expansion coefficient and high heat dissipation semiconductor carrier If you use It is possible to quickly release the heat generated by the semiconductor element to the outside of the system.
[0079]
In the above-described embodiment, the example in which the semiconductor carrier and the semiconductor package of the present invention are applied to the optical semiconductor module has been described. However, the semiconductor carrier and the semiconductor package of the present invention are not limited to the optical semiconductor module, but various semiconductors. It can be used for a semiconductor device such as a semiconductor package in which an element is mounted and contained.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an example in which a semiconductor carrier of the present invention is applied to a semiconductor carrier used in a stem type optical semiconductor module.
FIG. 2 shows the coefficient of thermal expansion (ppm / K) and thermal conductivity (W / m · W) when the average grain size of W crystal grains and the mass ratio of Cu in a sintered body of a W—Cu alloy are changed. It is a figure which shows the relationship of K).
FIG. 3 shows the coefficient of thermal expansion (ppm / K) and thermal conductivity (W / m · W) when the average grain size of Mo crystal grains and the mass ratio of Cu in a sintered body of Mo—Cu alloy are changed. It is a figure which shows the relationship of K).
FIG. 4 is a diagram showing the relationship between the grain size of W crystal grains and the frequency when the average grain size of W crystal grains is 3 μm in a W—Cu alloy sintered body.
FIG. 5 is a diagram showing the relationship between the grain size of W crystal grains and the frequency when the average grain size of W crystal grains is 10 μm in a W—Cu alloy sintered body.
FIG. 6 is a perspective view showing a green body to be a semiconductor carrier formed by injection molding of composite metal powder.
7 is a perspective view showing a semiconductor carrier formed by sintering the green body of FIG. 5. FIG.
8 is a perspective view showing an optical semiconductor module formed by mounting a semiconductor laser or the like on the sintered body of FIG. 6. FIG.
9 is a perspective view showing the optical semiconductor module in a state where a cap (cover) is attached to the optical semiconductor module of FIG. 7;
FIG. 10 is a diagram showing the relationship of the temperature (° C.) of the semiconductor carrier with respect to the output (mW) of the semiconductor laser when a 980 nm band semiconductor laser is mounted.
FIG. 11 is a diagram showing the relationship of the temperature (° C.) of the semiconductor carrier with respect to the output (mW) of the semiconductor laser when a 1480 nm band semiconductor laser is mounted.
12 is a perspective view schematically showing a modified example of the mounting structure of the optical semiconductor module, FIG. 12 (a) is a view showing a first modified example, and FIG. 12 (b) is a second modified example. FIG. 12C is a diagram showing a third modification.
13 is a perspective view schematically showing a modified example of the mounting structure of the optical semiconductor module, FIG. 13 (a) is a view showing a fourth modified example, and FIG. 13 (b) is a fifth modified example. FIG. 13C is a diagram showing a sixth modification.
14 is a perspective view schematically showing a modified example of the mounting structure of the optical semiconductor module, FIG. 14 (a) is a view showing a seventh modified example, and FIG. 14 (b) is an eighth modified example. FIG.
15 is a perspective view schematically showing a modified example of the mounting structure of the optical semiconductor module, FIG. 15 (a) is a view showing a ninth modified example, and FIG. 15 (b) is a tenth modified example. FIG. 15C is a diagram illustrating an eleventh modification.
16 is a perspective view schematically showing a modified example of the mounting structure of the optical semiconductor module, FIG. 16 (a) is a view showing a twelfth modified example, and FIG. 16 (b) is a thirteenth modified example. FIG. 16C is a diagram showing a fourteenth modification.
FIG. 17 is a perspective view schematically showing a package for a semiconductor element used for manufacturing a DIP type optical semiconductor module.
FIG. 18 is a perspective view schematically showing a CAN type optical semiconductor module.
[Explanation of symbols]
10 ... Semiconductor carrier, 10A DESCRIPTION OF SYMBOLS ... Green body, 11 ... Carrier base, 12 ... Mounting part, 12a ... Opening, 13 ... Cap fixing part, 14 ... Terminal part, 14a ... Through-hole, 15 ... Mount part, 20 ... Optical semiconductor module, 21 ... Semiconductor laser element 22 ... light receiving element, 23 ... lead wire, 24 ... ground wire, 25 ... glass adhesive, 26 ... cap, 27 ... optical fiber, 28, 29, 30, 31, 32, 33, 34, 35, 37, 38 , 40, 41, 42... Fixed part, 28a, 29a, 30a, 31a, 32a, 33a, 34a, 35a, 37a, 38a, 40a, 41a, 42a ... carrier holding part, 28b, 29b, 30b, 31b, 32b, 33b, 34b, 35b, 37b, 38b, 40b, 41b, 42b ... mounting portion, 50a, 50b ... package for semiconductor elements, 51 ... frame member, 5 a ... window holder, 52 ... main body, 53 ... bottom, 54 ... fixing part, 54a ... fixing hole, 55 ... lid member, 56 ... frame member, 56a ... window holder, 57 ... main body, 58 ... bottom, 59 ... Fixing part, 59a ... fixing hole, 60 ... CAN type optical semiconductor module, 61 ... carrier base, 62 ... mount part, 63 ... cap, 64 ... lens, 65 ... lead wire

Claims (5)

A semiconductor carrier comprising a carrier base having a mount portion for mounting a semiconductor element,
The carrier base having the mount portion is a sintered body of a WCu alloy of a formed body integrally formed in a three-step step shape by injection molding of W-Cu composite metal powder or mixed metal powder of W powder and Cu powder. Or a sintered body of a MoCu alloy of a molded body integrally molded so as to have a three-step step shape by injection molding of Mo-Cu composite metal powder or mixed metal powder of Mo powder and Cu powder,
The average grain size of the W and Mo crystal grains constituting the sintered body is 3 μm or less, and the ratio of Cu constituting the sintered body is 5 wt% or more and 30 wt% or less with respect to the mass of the sintered body. As well as
The three stages include a first stage that is a flat plate-shaped mounting part having a rectangular planar shape, a second stage that is a cylindrical cap fixing part for fixing the cap, and a circle having a smaller diameter than the second stage. A semiconductor carrier comprising a third stage which is formed in a column shape and serves as a terminal portion for fixing a plurality of leads.   2. The semiconductor carrier according to claim 1, wherein the semiconductor element is a semiconductor laser having an oscillation wavelength band of 980 nm and an oscillation output of 120 mW or less.   2. The semiconductor carrier according to claim 1, wherein the semiconductor element is a semiconductor laser having an oscillation wavelength of 1480 nm and an oscillation output of 90 mW or less.   4. The semiconductor carrier according to claim 2, wherein a surface of the mount portion on which the semiconductor laser is mounted is smoothed by secondary processing. A method of manufacturing a semiconductor carrier comprising a carrier base having a mount portion on which a semiconductor element is mounted,
The average particle size of the W-Cu composite metal powder or the mixed metal powder of W powder and Cu powder adjusted so that the W content is 95 to 70% by mass and the Cu content is 5 to 30% by mass is 0. A miniaturization step for miniaturization to 1 μm to 0.3 μm;
A planar shape in which a binder is added to the refined W-Cu composite metal powder or mixed metal powder of W powder and Cu powder, mixed and kneaded to form a molding composition, and then injection molded to form the bottom. Is a rectangular flat plate mounting part, a second stage is a cylindrical cap fixing part for fixing the cap, and a column having a smaller diameter than the second stage is used to fix a plurality of leads. A molded body forming step of integrally forming a three-stage stepped molded body composed of a third stage to be a terminal portion to be
And a sintering step of forming a sintered body by performing a sintering process so that the average grain size of the W crystal grains constituting the sintered body is 3 μm or less after the binder is debindered. A method of manufacturing a semiconductor carrier characterized by the above.

Images