WO2021106620A1 - Heat dissipation chip - Google Patents

Abstract

This heat dissipation chip (130) is used to dissipate heat from a circuit board. The heat dissipation chip (130) comprises: an insulating member (140); and a first electrode (151) and a second electrode (152). The insulating member (130) includes: a first main surface (1411) and a second main surface (1412) having a rectangular parallelepiped shape and facing each other; and a first side surface (1421) to a fourth side surface (1424) connecting the first main surface and the second main surface. The first electrode and the second electrode are formed at opposite ends of the insulating member. In the insulating member, the first side surface (1421) and the second side surface (1422) face each other, and the third side surface (1423) and the fourth side surface (1424) face each other. The first electrode is formed on the entire surface of the first side surface, a part of the first main surface, and a part of the second main surface. The second electrode is formed on the entire surface of the second side surface, a part of the first main surface, and a part of the second main surface. In a plan view of the heat dissipation chip as seen in a normal direction of the third side surface, the first electrode and the second electrode each have a substantially C shape.

Description

Heat dissipation chip

This disclosure relates to a heat dissipation chip for dissipating heat on a circuit.

Japanese Patent Application Laid-Open No. 2001-68877 (Patent Document 1) describes that in an electronic circuit having a transistor, a relatively large impedance is provided between a copper foil pattern to which a collector of the transistor is connected and a ground line or a power supply line. A configuration is disclosed in which a circuit component (resistor, capacitor, coil) to be provided is arranged to form a heat dissipation path for heat generated by a transistor.

Japanese Unexamined Patent Publication No. 2001-68877

When a circuit component such as a resistor, a capacitor, or a coil is used as a heat dissipation path as in JP-A-2001-68877 (Patent Document 1), these are used in order not to impair the electrical characteristics of the electronic circuit. It is necessary to increase the impedance of circuit components. However, even when a component having a high impedance is used, the resistance component may cause not a little self-heating, or the switching loss of the transistor may increase due to the charging / discharging of the capacitor.

The present disclosure has been made to solve the above-mentioned problems, and the purpose of the present disclosure is to dissipate heat on the circuit without giving an electrical influence to the circuit.

The heat dissipation chip according to the present disclosure is used to dissipate heat from the circuit board. The heat radiating chip includes an insulating member and a first electrode and a second electrode. The insulating member has a rectangular parallelepiped shape and includes a first main surface and a second main surface facing each other, and first to fourth side surfaces connecting the first main surface and the second main surface. The first electrode and the second electrode are formed at opposite ends of the insulating member. In the insulating member, the first side surface and the second side surface face each other, and the third side surface and the fourth side surface face each other. The first electrode is formed on the entire surface of the first side surface, a part of the first main surface, and a part of the second main surface. The second electrode is formed on the entire surface of the second side surface, a part of the first main surface, and a part of the second main surface. When the heat radiating chip is viewed in a plan view from the normal direction of the third side surface, the first electrode and the second electrode have a substantially C shape.

Preferably, the first side surface has a rectangular shape with a long side and a short side. The aspect ratio indicated by the length of the long side to the length of the short side is greater than 1.

Preferably, the first electrode and the second electrode are not formed on the third side surface and the fourth side surface.

Preferably, the insulating member is formed of a ceramic material containing alumina, aluminum nitride, silicon nitride, or silicon carbide, or a compound containing them.

Preferably, the thermal conductivity of the insulating member is greater than 2 W / m · K.

According to the heat dissipation chip according to the present disclosure, by arranging the heat dissipation chip formed of the insulating member in the circuit, heat can be transferred to other parts of the circuit board (for example, the ground electrode) via the heat dissipation chip. it can. Therefore, heat can be dissipated without affecting the circuit electrically.

This is an example of an electronic circuit in which a heat radiating chip according to an embodiment is arranged. It is a perspective view of the heat dissipation chip according to an embodiment. It is a top view of the heat dissipation chip of FIG. It is a side view of the heat dissipation chip of FIG. It is a figure which shows the electronic circuit of the comparative example 1. FIG. It is an external view of the diode in the circuit of FIG. It is a plan perspective view of the diode of FIG. It is a figure for demonstrating heat dissipation by a heat dissipation chip in the circuit of FIG. This is an example of temperature distribution simulation in the circuit of Comparative Example 1. It is a figure which shows the temperature distribution simulation at the time of arranging two heat dissipation chips. It is a figure which shows the temperature distribution simulation at the time of arranging four heat dissipation chips. It is an example of another circuit in which the heat dissipation chip according to the embodiment is arranged. It is a figure which shows the circuit of the comparative example 2. It is a figure for demonstrating heat dissipation by a heat dissipation chip in the circuit of FIG.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The same or corresponding parts in the drawings are designated by the same reference numerals, and the description thereof will not be repeated.

FIG. 1 is a diagram showing an example of an electronic circuit 100 in which a heat radiating chip 130 according to the present embodiment is arranged. With reference to FIG. 1, the electronic circuit 100 includes an integrated circuit (LSI) 105, capacitors C1 and C2, a diode D1, an inductor L1, and a heat dissipation chip 130. The LSI 105 includes a control circuit 110 and a switching element SW1. The electronic circuit 100 is a chopper-type step-down DC / DC converter that steps down the power supply voltage from the DC power source PS and supplies it to the load 120.

The capacitor C1 is connected between the positive electrode terminal and the negative electrode terminal of the DC power supply PS. The capacitor C1 smoothes the DC voltage from the DC power supply PS and supplies it to the electronic circuit 100.

The switching element SW1 and the diode D1 are connected in series between the positive electrode terminal and the negative electrode terminal (GND) of the DC power supply PS. The switching element SW1 is, for example, a field effect transistor (MOSFET), the drain of which is connected to the positive electrode terminal of the DC power supply PS, and the source of which is connected to the cathode of the diode D1. The diode D1 is, for example, a Schottky diode, and the anode is connected to the negative electrode terminal of the DC power supply PS.

One end of the inductor L1 is connected to a connection node (TS) between the switching element SW1 and the diode D1. The load 120 is connected between the other end of the inductor L1 and the negative electrode terminal (GND) of the DC power supply PS. The capacitor C2 is connected in parallel with the load 120 to smooth the output voltage supplied to the load 120.

The control circuit 110 is driven by a DC voltage from the DC power supply PS and outputs a control signal to the gate of the switching element SW1. The switching element SW1 is controlled by a control signal from the control circuit 110, and is switched between conducting and non-conducting. By the control by the control circuit 110, when the switching element SW1 is put into a conductive state, the diode D1 is put into a non-conducting state, and conversely, when the switching element SW1 is put into a non-conducting state, the diode D1 is put into a conductive state. That is, the switching element SW1 and the diode D1 complementarily switch between conduction and non-conduction. Then, by adjusting the duty of the switching element SW1, the DC voltage supplied to the load 120 can be adjusted.

Further, in the electronic circuit 100 of the embodiment, the heat dissipation chip 130 is connected in parallel with the diode D1.

In such an electronic circuit 100, the electronic components may generate heat by performing the switching operation. In particular, the Schottky barrier diode used as the diode D1 has the characteristics that the forward voltage characteristic is low and the switching characteristic is fast as compared with a general PN junction diode, while a large current flows in the forward direction. Therefore, the calorific value tends to increase. Further, since the Schottky barrier diode has a relatively large leakage current, the temperature of the circuit around the element also rises when the heat generated by the element increases. Then, not only the diode D1 but also other elements such as the control circuit 110 or the switching element SW1 may be caused to deteriorate the characteristics and the life.

In the electronic circuit 100 of the present embodiment, as described above, the heat dissipation chip 130 is connected in parallel to the diode D1 that generates a large amount of heat. As will be described later, the heat dissipation chip 130 can efficiently transfer the heat generated by the diode D1 to the ground electrode of the substrate on which the electronic circuit 100 is formed.

Next, the details of the heat radiating chip 130 will be described with reference to FIGS. 2 to 4. FIG. 2 is a perspective view of the heat radiating chip 130 in FIG. FIG. 3 is a plan view when the heat radiating chip 130 is viewed from the Z-axis direction of FIG. 2, and FIG. 4 is a side view of the heat radiating chip 130 when the heat radiating chip 130 is viewed from the X-axis direction of FIG.

With reference to FIGS. 2 to 4, the heat radiating chip 130 includes an insulating member 140 having a rectangular parallelepiped shape, and first electrodes 151 and second electrodes 152 formed at both ends of the insulating member 140. The insulating member 140 includes a first main surface 1411 and a second main surface 1412, and first to fourth side surfaces connecting the two main surfaces. The first main surface 1411 and the second main surface 1412 are planes parallel to the XY plane in the figure, and the first side surface 1421 and the second side surface 1422 are planes parallel to the ZX plane in the figure. The third side surface 4123 and the fourth side surface 1424 are planes parallel to the YZ plane in the figure.

The first electrode 151 is formed on the entire surface of the first side surface 1421 of the insulating member 140 and on the ends of the first main surface 1411 and the second main surface 1412 on the first side surface 1421 side. Further, the second electrode 152 is formed on the entire surface of the second side surface 1422 of the insulating member 140 and on the ends of the first main surface 1411 and the second main surface 1412 on the second side surface 1422 side. As shown in FIG. 4, when the heat radiation chip 130 is viewed in a plan view from the normal direction (that is, the X-axis direction) of the third side surface 1423, the first electrode 151 and the second electrode 152 have a substantially C shape. doing. In other words, the first electrode 151 and the second electrode 152 are not formed on the second side surface 1422 and the fourth side surface 1424.

In the manufacturing process of the heat radiating chip 130, the first electrode 151 and the second electrode 152 are formed at the ends of the large insulating member extending in the X-axis direction in the Y-axis direction in FIG. 2, for example, by plating, and then Y. By cutting along the axial direction, individual heat dissipation chips 130 are formed. Therefore, when the heat radiating chip 130 is viewed in a plan view from the X-axis direction, the first electrode 151 and the second electrode 152 have a substantially C shape. For cutting into individual heat radiating chips 130, a method of dicing or splitting with a belt is adopted. Therefore, the second side surface 1422 and the fourth side surface 1424 along the Y axis of the heat radiating chip 130 are not smooth surfaces, but unevenness due to cutting marks or burrs is generated.

The first electrode 151 and the second electrode 152 may be formed of a plurality of layers using the same material or different materials. As an example, the electrode is formed by subjecting an internal electrode formed of copper paste on the insulating member 140 to nickel plating, and further plating the nickel plating with solder.

Assuming that the length of the long side along the X axis of the heat radiation chip 130 is LX and the length of the short side along the Z axis is LZ, the aspect ratio (LX / LZ) indicated by the length of the long side with respect to the short side. ) Is greater than 1. Further, the size of the heat radiating chip 130 is formed to be the same size as other electronic components (resistors, coils, capacitors, etc.) arranged on the electronic circuit board. Therefore, the heat radiating chip 130 can be arranged on the circuit together with other electronic components in the process of mounting various electronic components on the substrate.

Insulating member 140, such as alumina, aluminum nitride, silicon nitride, ceramic materials such as silicon carbide or is formed by compounds containing ^{them, 1.0 × 10 3 [Ω ·} m] or more volume resistivity Has. Further, the insulating member 140 has a thermal conductivity of 2 W / m · K or more. As described above, in the heat radiating chip 130, the insulating member 140 having high resistance and high heat transfer property has a shape sandwiched between the first electrode 151 and the second electrode 152. Therefore, by connecting the first electrode 151 and the second electrode 152 to the conductive path in the electronic circuit, the heat of the conductive path can be transferred without affecting the electrical characteristics of the electronic circuit.

FIG. 5 is a diagram showing the electronic circuit 100 # of Comparative Example 1. The electronic circuit 100 # has a configuration in which the heat radiating chip 130 in the electronic circuit 100 of FIG. 1 is not provided, and other elements are the same as those of the electronic circuit 100. Hereinafter, the effect of the heat radiating chip 130 will be described by comparing the electronic circuit 100 of FIG. 1 and the electronic circuit 100 # of FIG.

FIG. 6 is an example of an external view of the diode D1 in FIGS. 1 and 5. Further, FIG. 7 is a perspective perspective view of the diode D1 of FIG. With reference to FIGS. 6 and 7, the diode D1 is a Schottky diode having a so-called TO (Top Outline) system package, and the cathode electrode 20 and the anode electrode 30 formed in the package 10 are The substrate 40 on which the diode body is formed is included.

The substrate 40 is arranged on the cathode electrode 20. The substrate 40 is electrically connected to the cathode electrode 20 by an electrode pad (not shown) formed on the lower surface of the substrate 40. On the other hand, the substrate 40 and the anode electrode 30 are electrically connected by wire bonding 50. A part of the cathode electrode 20 and the anode electrode 30 protrudes to the outside of the package 10 for connecting to the circuit board.

As described above, the Schottky barrier diode has the characteristics that the forward voltage characteristic is low and the switching characteristic is fast as compared with a general PN junction diode, but it generates heat because a large current flows in the forward direction. The amount tends to be large. However, in the case of a Schottky barrier diode having a TO-based package as shown in FIGS. 6 and 7, the substrate 40 that generates heat and the anode electrode 30 are connected by a wire bonding 50 having a narrow line width, so that the substrate is connected. The heat generated in 40 is not easily transferred to the anode electrode 30, and the heat tends to stay on the cathode electrode 20 side.

FIG. 8 is a diagram for explaining a specific arrangement of the heat dissipation chip 130 on the substrate of the electronic circuit and heat dissipation by the heat dissipation chip. In FIG. 8, FIG. 8A in the upper row is an example of arrangement of electronic components in the electronic circuit 100 # of Comparative Example 1, and FIG. 8B in the lower row is an arrangement of electronic components in the electronic circuit 100 of the present embodiment. This is an example.

In the electronic circuits 100 and 100 #, the cathode of the diode D1 is connected to the electrode TS which is a connection node between the switching element SW1 and the inductor L1, and the anode is connected to the ground electrode TG which is the ground potential GND. Generally, the ground electrode often has a relatively large area even in the substrate, but as shown in FIG. 8, the electrode TS to which the cathode is connected is isolated from other electrodes on the substrate. In many cases, the area of the electrode tends to be smaller than that of the ground electrode TG. Therefore, in the electronic circuit 100 # of Comparative Example 1, the heat generated by the diode D1 stays in the cathode electrode 20 of the diode D1 and the electrode TS connected to the cathode electrode 20. Then, not only the diode D1 but also the switching element SW1 and the control circuit 110 around the diode D1 may rise in temperature, which may cause deterioration or malfunction of these devices.

On the other hand, in the electronic circuit 100 of the present embodiment, the heat dissipation chip 130 is connected in parallel with the diode D1. Therefore, the heat generated in the diode D1 can be transferred from the electrode TS to the ground electrode TG through the heat dissipation chip 130 in addition to the path of the wire bonding 50 inside the diode D1 (arrow in FIG. 8B). AR1). Therefore, the heat generated by the diode D1 is suppressed from staying in the electrode TS, and the influence on the diode D1 and the surrounding equipment can be reduced.

9 to 10 are diagrams showing temperature distributions when a temperature simulation is performed when a DC / DC converter is operated in the electronic circuit 100 # of Comparative Example 1 and the electronic circuit 100 of the present embodiment. .. FIG. 9 is a simulation example of the electronic circuit 100 # in the modified example. FIG. 10 shows a simulation example when two heat radiating chips 130 are used, and FIG. 11 shows a simulation example when four heat radiating chips 130 are used.

In FIGS. 9 to 11, the left figure (a) shows the arrangement of electronic components on the substrate, and the right figure (b) shows the temperature distribution. In the figure on the right (b), the temperature distribution is shown by contour lines, and the high temperature portion is hatched. The higher the hatching concentration, the higher the temperature. Further, in the right figure (b), the positions of electronic components (LSI, diode, inductor) on the substrate are indicated by broken lines. In the simulation, the calculation is performed with the ambient temperature Ta as 25.2 ° C., and the temperature Tj of the portion of the substrate 40 in the diode D1 is also shown.

In the simulation of Comparative Example 1 in FIG. 9, the portion having the highest temperature is the portion of the substrate 40 of the diode D1, and the temperature is 58.5 ° C. As described above, since the substrate 40 and the anode electrode 30 are connected by wire bonding 50 having a narrow line width, heat is not transferred much from the substrate 40, and the temperature rise is small.

When the heat dissipation chip 130 is arranged between the electrode TS and the ground electrode TG as shown in FIGS. 10 and 11, the area of the high temperature region in the diode D1 is smaller than that in Comparative Example 1 of FIG. You can see that. Further, the shape is such that contour lines project from the position where the heat radiating chip 130 is arranged toward the left ground electrode TG (region RG1 in FIGS. 10 and 11), and the heat from the electrode TS is radiated from the heat radiating chip. It can be seen that it is diffused to the ground electrode TG through 130. As a result, the temperature Tj of the portion of the substrate 40 is lowered to 57.3 ° C. in the case of FIG. 10 and to 56.7 ° C. in the case of FIG. 11.

When compared in terms of thermal resistance, in the comparative example of FIG. 9, θja = 52.9 ° C./W, but in the case of FIG. 10, θja = 51.0 ° C./W, which is a reduction of about 3.6%. Further, in the case of FIG. 11, θja = 50.0 ° C./W, which is a reduction of about 5.5%. The number of heat radiating chips 130 to be arranged is appropriately selected according to the heat generation state in the circuit and the temperature specifications of each element and the circuit.

As described above, by arranging the heat dissipation chip formed of the insulating member between the heat generating portion on the circuit board and the electrode having a relatively low temperature and high heat dissipation efficiency such as the ground electrode, the electronic circuit can be formed. It is possible to efficiently dissipate heat without affecting the electrical characteristics. Further, by forming the heat-dissipating chip in the same size as other electronic components mounted on the circuit board, the heat-dissipating chip can be arranged in the mounting process of other electronic components, so that a member such as a heat sink is separately arranged. It does not require an additional process and can suppress an increase in manufacturing cost as compared with the case where it is used.

(Modification example)
In FIG. 1, an example in which the heat radiating chip according to the present embodiment is applied to the electronic circuit of the step-down DC / DC converter has been described, but the heat radiating chip can also be applied to the electronic circuit included in other devices. is there.

FIG. 12 is a circuit diagram of a modified example in which the heat radiating chips 230 and 240 according to the present embodiment are applied to a boost type DC / DC converter. Further, FIG. 13 is a circuit diagram of the DC / DC converter of Comparative Example 2 in which the heat dissipation chips 230 and 240 are not arranged.

With reference to FIGS. 12 and 13, the electronic circuits 200 and 200 # include an integrated circuit (LSI) 205, capacitors C3 and C4, a diode D2, and an inductor L2. The LSI 205 includes a control circuit 210 and a switching element SW2. The electronic circuits 200 and 200 # are chopper-type step-up DC / DC converters that boost the power supply voltage from the DC power supply PS and supply it to the load 120.

The capacitor C3 is connected between the positive electrode terminal and the negative electrode terminal of the DC power supply PS. The capacitor C3 smoothes the DC voltage from the DC power supply PS and supplies it to the electronic circuits 200 and 200 #.

The inductor L2 and the switching element SW2 are connected in series between the positive electrode terminal and the negative electrode terminal (ground potential GND) of the DC power supply PS. One end of the inductor L2 is connected to the positive electrode terminal of the DC power supply PS. The switching element SW1 is, for example, a MOSFET, the drain is connected to the other end of the inductor L2, and the source is connected to the negative electrode terminal (GND) of the DC power supply PS.

The diode D2 is, for example, a Schottky diode, the anode is connected to the connection node (TS) between the inductor L2 and the switching element SW2, and the cathode is connected to the load 220. The load 220 is connected between the other end of the diode D2 and the negative electrode terminal (ground potential GND) of the DC power supply PS. The capacitor C4 is connected in parallel with the load 120 to smooth the output voltage supplied to the load 220.

The control circuit 210 is driven by a DC voltage from the DC power supply PS and outputs a control signal to the gate of the switching element SW2. The switching element SW2 is controlled by a control signal from the control circuit 210, and is switched between conducting and non-conducting. By the control by the control circuit 210, when the switching element SW2 is in the conductive state, the diode D2 is in the non-conducting state, and conversely, when the switching element SW2 is in the non-conducting state, the diode D2 is in the conductive state. That is, the switching element SW2 and the diode D2 are complementary to each other to switch between conduction and non-conduction. Then, by adjusting the duty of the switching element SW2, the DC voltage supplied to the load 220 can be adjusted.

Then, in the electronic circuit 200 of FIG. 12, the heat radiating chip 230 is connected in parallel to the switching element SW2, and the heat radiating chip 240 is further connected in parallel to the capacitor C4.

FIG. 14 is a diagram for explaining a specific arrangement of heat dissipation chips on the substrate of the electronic circuit in the modified example and heat dissipation by the heat dissipation chips. In FIG. 14, FIG. 14 (a) in the upper row is an example of arrangement of electronic components in the electronic circuit 200 # of Comparative Example 2, and FIG. 14 (b) in the lower row is an arrangement of electronic components in the electronic circuit 200 of the present embodiment. This is an example.

As described in the embodiment with reference to FIG. 14, in the diode D2, heat is mainly generated in the substrate arranged on the electrode on the cathode side, so that the output electrode Vout connected to the cathode of the diode D2 Heat is transferred to the diode. Since the output electrode Vout is also connected to the load 220, if the heat transferred to the output electrode Vout can be appropriately diffused in the circuit on the load 220 side, heat retention in the output electrode Vout is unlikely to occur.

However, for example, when a filter circuit is provided in a portion of the load 220 connected to the output electrode Vout, the heat of the output electrode Vout cannot be diffused in the load 220, and the heat of the output electrode Vout cannot be diffused. May stay. Therefore, in the electronic circuit 200, the heat dissipation chip 240 is arranged between the output electrode Vout and the ground electrode TG, whereby the heat of the output electrode Vout is transferred to the ground electrode TG (arrow AR3 in FIG. 14). ).

Further, in the case of a step-up DC / DC converter, the electrode TS to which the inductor L2, the switching element SW2, and the diode D2 are connected is formed in a manner isolated from other electrodes on the substrate. Similar to the diode D2, the switching element SW2 also tends to generate heat because it can switch between conducting and non-conducting in the switching operation. As shown in FIG. 14, when the switching element SW2 is formed of the TO system package like the diode D2, the substrate on which the transistor is formed is arranged on the drain electrode connected to the electrode TS. In this case, as described with reference to FIGS. 6 and 7, heat tends to stay on the electrode TS side. Therefore, in the electronic circuit 200 of the modified example, the heat radiating chip 230 is also arranged between the electrode TS and the ground electrode TG. As a result, the heat accumulated on the electrode TS side can be transferred to the ground electrode TG (arrow AR2 in FIG. 14).

As described above, even in the case of the boost type DC / DC converter, an insulating member is formed between the heat generating portion on the circuit board and the electrode having a relatively low temperature and high heat dissipation efficiency such as a ground electrode. By arranging the heat radiating chip, it is possible to efficiently radiate heat without affecting the electrical characteristics of the electronic circuit.

Even in electronic circuits other than DC / DC converters (for example, AC / DC converters or DC / AC converters) as shown in FIGS. 1 and 12, heat dissipation chips are placed on the circuit board where heat tends to accumulate. May be placed.

The embodiments disclosed this time should be considered to be exemplary in all respects and not restrictive. The scope of the present disclosure is indicated by the scope of claims rather than the description of the embodiment described above, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

10 packages, 20 cathode electrodes, 30 anode electrodes, 40 substrates, 50 wire bonding, 100,200 electronic circuits, 110,210 control circuits, 120,220 loads, 130,230,240 heat dissipation chips, 140 insulating members, 151,152 , TG, TS, Vout electrode, 1411, 1412 main surface, 1421-1424 side surface, C1 to C4 capacitor, D1, D2 diode, GND ground potential, L1, L2 inductor, PS DC power supply, SW1, SW2 switching element.

Claims (5)

It is a heat dissipation chip for dissipating heat from the circuit board.
An insulating member having a rectangular parallelepiped shape and including the first and second main surfaces facing each other and the first to fourth side surfaces connecting the first main surface and the second main surface.
A first electrode and a second electrode formed at opposite ends of the insulating member are provided.
In the insulating member, the first side surface and the second side surface face each other, and the third side surface and the fourth side surface face each other.
The first electrode is formed on the entire surface of the first side surface, a part of the first main surface, and a part of the second main surface.
The second electrode is formed on the entire surface of the second side surface, a part of the first main surface, and a part of the second main surface.
When the heat radiating chip is viewed in a plan view from the normal direction of the third side surface, the first electrode and the second electrode have a substantially C shape. The first side surface has a rectangular shape having a long side and a short side.
The heat radiating chip according to claim 1, wherein the aspect ratio indicated by the length of the heat radiating chip along the long side to the length of the heat radiating chip along the short side is larger than 1. The heat radiating chip according to claim 1 or 2, wherein the first electrode and the second electrode are not formed on the third side surface and the fourth side surface. The heat-dissipating chip according to any one of claims 1 to 3, wherein the insulating member is made of a ceramic material containing alumina, aluminum nitride, silicon nitride, or silicon carbide, or a compound containing them. The heat-dissipating chip according to any one of claims 1 to 4, wherein the heat conductivity of the insulating member is larger than 2 W / m · K.

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