JP2008244288A - Semiconductor device provided with temperature control device and printed circuit board - Google Patents

Abstract

Provided are a semiconductor device and a printed circuit board which have improved durability and reliability by preventing deterioration due to heat distortion caused by heat generation of a heat-generating component of a semiconductor chip.
A semiconductor device including a semiconductor substrate including a temperature control device, a semiconductor chip disposed on the semiconductor substrate, and a heat dissipating member that dissipates heat generated by the semiconductor chip. And the printed circuit board which mounted | wore this semiconductor device 1 on the printed circuit board provided with the temperature control apparatus 7b. As the temperature control device 7b, a temperature measuring device such as the thermistor 6a, 6c, 6d is arranged on each member, and the temperature of each member is directly measured to control the heating value of the heater so that each member has a predetermined temperature. May be.
[Selection] Figure 1

Description

  The present invention relates to a semiconductor device and a printed circuit board provided with a temperature control device, and more particularly to a semiconductor device and a printed circuit board provided with a temperature control device, and a temperature control method for the semiconductor device and the printed circuit board.

  Semiconductor chips, particularly highly integrated semiconductor chips, generate heat during operation. This amount of generated heat has an adverse effect on the semiconductor chip itself and the connection portion unless a heat dissipation mechanism is provided to dissipate heat. For this reason, the semiconductor device is provided with a metal heat radiating plate and a heat radiating member, which are brought into close contact with the semiconductor chip to radiate heat generated from the semiconductor chip to the outside of the semiconductor device. As a result, the semiconductor device does not rise above a certain temperature, and the semiconductor chip itself and peripheral members are not damaged by the high temperature.

  In recent years, however, the amount of heat generated has been increasing as semiconductor chips have been highly integrated. For this reason, the heat dissipation mechanism has also been improved in performance. For example, a package type heat dissipation member called a heat spreader can dissipate a large amount of heat generated in the semiconductor chip. The fact that the heat transfer occurs in a short time means that the time from the room temperature to the temperature state during steady operation is short as at the start of operation of the semiconductor chip. That is, the semiconductor chip becomes a high temperature state during steady operation in a short time. However, the semiconductor substrate bonded to the semiconductor chip only by the electrode portion has poor thermal conductivity and does not immediately rise in temperature. In particular, in a semiconductor substrate made of a resin or ceramic material having a low thermal conductivity, the temperature rise is slow. If it does so, a temperature difference will arise between a semiconductor chip and a thermal radiation member, and a semiconductor substrate. For this reason, a difference in thermal expansion occurs between the semiconductor chip and the heat radiating member and the semiconductor substrate, and a thermal stress is generated at these joints. Such stress due to the difference in thermal expansion may be caused by the difference in the thermal expansion coefficient of each material.

  If the degree of integration of the semiconductor chip is not so large or the speed is not increased, the amount of heat generated is relatively small, and such stress does not cause a problem. Recently, however, semiconductor chips have been highly integrated and increased in speed, and the deterioration of the durability of semiconductor devices due to this thermal stress has become a problem. When such a thermal stress is repeatedly applied to the semiconductor device, there is a possibility that a joint portion such as a bump electrode that joins the semiconductor chip and the semiconductor substrate is damaged. In particular, when thermal stress is applied when the joint becomes high temperature, the joint having poor heat resistance is often easily damaged.

  According to the inventors' heat cycle simulation experiment, the durability of the semiconductor device against temperature changes is not a problem in a normal use situation, but is a problem in an application requiring high reliability. In particular, it has been found that the longer the temperature change acting on the semiconductor device, the shorter the life of the semiconductor device. FIG. 8 shows a life test result by heat cycle of a semiconductor device mounted with a highly integrated semiconductor chip. In the graph of FIG. 8, it represents with the cycle number until the lifetime with respect to the temperature difference in a heat cycle comes. As can be seen from the figure, there is a first-order correlation between the temperature difference and the life in the heat cycle, and the life is shorter as the temperature difference is larger. Moreover, if the temperature difference is 140 ° C. or more, the lifetime is 1000 cycles or more. Although this level of reliability can be used with ordinary business personal computers, this is not enough for devices used for network hosts that require high reliability and important data storage devices. I can't say that.

  Further, similarly to the above-described problem in the semiconductor device, the printed circuit board has a problem of thermal stress due to a temperature difference between the heat generated in the semiconductor device and a printed circuit board on which the semiconductor device is mounted. Similar to the damage caused by the stress at the joint between the semiconductor chip and the semiconductor substrate in the semiconductor device, in the printed circuit board, the damage due to the stress at the joint between the semiconductor device and the printed board becomes a problem (in this application, the print An electronic device in which a semiconductor device, an electronic component, or an electrical component is mounted on a substrate is called a printed circuit board.) Up to now, even though the heat resistance of semiconductor devices and printed circuit boards has been studied, the study on the thermal stress accompanying the temperature difference has not been so much conscious except for dealing with special circumstances.

  For example, Patent Document 1 reports on countermeasures against adverse effects caused by thermal stress during repair of a printed circuit board. Patent Document 1 discloses an invention in which there is a local heating step such as soldering when repairing or remodeling a multilayer printed wiring board, and warping or distortion of the multilayer printed wiring board is prevented by residual stress at that time. . As a specific method, a heat generating layer with a built-in heater is arranged in the intermediate layer of the multilayer printed wiring board. When soldering, the heat generating layer generates heat and the entire multilayer printed circuit board is heated to locally This prevents a large temperature difference from occurring.

Patent Document 2 discloses a heater built-in substrate. This is because the heater is built in the substrate of the electronic device used in outer space, and the semiconductor device etc. is efficiently used by the heater built-in substrate in order to prevent the semiconductor device etc. from being exposed to the cryogenic state and becoming inoperable. The electronic equipment is kept warm.
JP 2001-111121 A JP-A-6-344996

  As described above, a multilayer printed wiring board having a temperature adjustment function by a heater is disclosed. However, in Patent Document 1, this temperature adjustment function stops the operation of the multilayer printed wiring board and performs soldering or the like. It is for measures against thermal stress against local heating when repairing. For this reason, the entire multilayer printed wiring board in which the operation is stopped is heated isothermally, and there is no function to compensate for thermal distortion caused by heat generation of the semiconductor device or the like during operation of the multilayer printed wiring board or at the start of operation. Also, in the heater-embedded substrate disclosed in Patent Document 2, this heater has a heat retaining function for smooth operation of the semiconductor device or the like in an extremely low temperature state, but due to heat generated by the operating semiconductor device or the like. There is no function to compensate for thermal distortion.

  In this way, in conventional semiconductor devices and printed circuit boards equipped with the semiconductor devices, local temperature differences that occur at the start of operation, and temperature control of each part to relieve stress on the joints due to distortion caused by this difference Is not a problem, and it cannot be applied to the printed circuit board as described above.

  The present invention has been made in view of the above points, and prevents deterioration due to heat distortion of a semiconductor device due to heat generation of a heat-generating component such as a semiconductor chip and a printed circuit board on which the semiconductor device is mounted, thereby improving durability and reliability. An object of the present invention is to provide a semiconductor device and a printed circuit board, and to provide a temperature control method for improving durability and reliability of the semiconductor device and the printed circuit board.

  In order to solve the above-described problems, the present invention is characterized by the following measures.

  A semiconductor device of the present invention includes a semiconductor substrate, a semiconductor chip disposed on the semiconductor substrate, and a heat dissipation member that dissipates heat generated by the semiconductor chip, and the semiconductor substrate includes a temperature control device. It is characterized by that. Furthermore, the semiconductor chip and the heat radiating member may also include a temperature control device. The temperature control device preferably includes a heater and a power supply control device for the heater, and more preferably includes a temperature measurement device such as a thermistor. The temperature measuring device can also preheat control a temperature control object such as a semiconductor substrate before starting the operation of the semiconductor device so as to reduce thermal distortion of the semiconductor device due to heat generation of the semiconductor chip at the start of operation of the semiconductor device. . Preheating control can be performed by preheating the temperature control object for a predetermined time, in particular, preheating the temperature control object when the temperature control object is below the predetermined temperature, or preheating until the temperature control object exceeds the predetermined temperature. It is preferable that it can also be performed.

  In the semiconductor device of the present invention, even if the operation and stop of the semiconductor device are repeated, the thermal stress accompanying the heat generation of the semiconductor chip is not applied to the semiconductor substrate or the junction between the semiconductor chip and the semiconductor substrate, or the thermal stress is small. There is no risk of repeated damage, and the long-term reliability of the semiconductor device is improved. The temperature control by the heater and the power supply control device for the heater is a temperature control device that is simple, highly accurate, and highly reliable. If a temperature measuring device such as a thermistor is provided, the temperature can be controlled with higher accuracy. Generally, in a semiconductor device, the temperature change due to heat generation is severe at the start of the operation of the semiconductor device, and therefore it is preferable that the temperature control at the start of the operation can be performed. This temperature control at the start of operation is temperature control including a preheating time slightly before the semiconductor device actually operates. In the preheating control, accurate and effective control can be performed by controlling by the preheating time or by controlling the temperature of the temperature control object.

  The printed circuit board of the present invention is provided with a temperature control device on a printed circuit board, and the semiconductor device of the present invention is mounted on the printed circuit board. Furthermore, electronic components, electrical components, printed circuit board reinforcement components, heat dissipation components, and printed circuit board protection components mounted on the printed circuit board may also include a temperature control device. The temperature control device preferably includes a heater and a power supply control device for the heater, and more preferably includes a temperature measurement device. The temperature measuring device can preheat control the temperature control object so as to reduce the thermal distortion of the printed circuit board due to heat generation of the semiconductor chip at the start of operation of the semiconductor device, or can preheat the temperature control object for a predetermined time. In addition, it is preferable that the temperature control object can be preheated when the temperature control object is equal to or lower than the predetermined temperature, or can be preheated until the temperature control object exceeds the predetermined temperature.

  In the printed circuit board of the present invention, even if the operation and stop of the printed circuit board are repeated, thermal stress due to heat generation of the semiconductor device or the like is not applied, or there is no risk of damage to the joint due to repeated thermal stress, Long-term reliability of the printed circuit board is improved. The temperature control by the heater and the power supply control device for the heater is a temperature control device that is simple, highly accurate, and highly reliable. If a temperature measuring device such as a thermistor is provided, the temperature can be controlled with higher accuracy. Generally, in the printed circuit board, the temperature change due to heat generation is severe at the start of the operation of the printed circuit board, and therefore it is preferable that the temperature control at the start of the operation can be performed. The temperature control at the start of operation is preferably temperature control including a preheating time slightly before the printed circuit board is actually operated. In the preheating control, accurate and effective control can be performed by controlling by the preheating time or by controlling the temperature of the temperature control object.

  The temperature control method for a semiconductor device according to the present invention includes a semiconductor substrate, a semiconductor chip disposed on the semiconductor substrate, and a heat dissipation member that dissipates heat generated by the semiconductor chip. It is the temperature control method to control. Furthermore, a temperature control method for controlling the temperature of the semiconductor chip and the heat dissipation member may be used. In this temperature control method for a semiconductor device, the temperature control object such as a semiconductor substrate is preheat controlled so as to reduce the thermal distortion of the semiconductor device due to heat generation of the semiconductor chip at the start of operation of the semiconductor device. It is preferable to perform preheating control for a predetermined time, to preheat the temperature control object when the temperature control object is below a predetermined temperature, and to preheat until the temperature control object exceeds a predetermined temperature. Moreover, in the temperature control method of the semiconductor device, it is preferable to control the temperature of the temperature control object by heating the heater.

  According to the temperature control method for a semiconductor device of the present invention, even if the semiconductor device is repeatedly activated and stopped, thermal stress due to heat generation of the semiconductor chip is not applied between the semiconductor substrate and the semiconductor chip, or is small due to repeated thermal stress. Long-term reliability is improved with no reduction in service life. If a temperature measuring device such as a thermistor is provided, the temperature can be controlled with higher accuracy. Generally, in a semiconductor device, the temperature change due to heat generation is severe at the start of the operation of the semiconductor device, and therefore it is preferable that the temperature control at the start of the operation can be performed. This temperature control at the start of operation is temperature control including a preheating time slightly before the semiconductor device actually operates. In the preheating control, accurate and effective control can be performed by controlling by the preheating time or by controlling the temperature of the temperature control object such as a semiconductor substrate. Moreover, the temperature control by the heater and the power supply control device for the heater is a temperature control method that is simple, highly accurate, and highly reliable.

  A temperature control method for a printed circuit board according to the present invention is a temperature control method for a printed circuit board in which a semiconductor device whose temperature is controlled by the above temperature control method is mounted on a printed circuit board, and controls the temperature of the printed circuit board. This is a temperature control method. Furthermore, a temperature control method for controlling the temperatures of electronic components, electrical components, printed circuit board reinforcement components, heat radiation components, and printed circuit board protection components mounted on the printed circuit board may be used. In this temperature control method, the temperature control object such as a printed circuit board is preheat controlled so as to reduce the thermal distortion of the printed circuit board due to heat generation of the semiconductor chip at the start of the operation of the printed circuit board. Pre-time control, pre-heating the temperature control object when the temperature control object is below the predetermined temperature, pre-heating until the temperature control object exceeds the predetermined temperature, temperature control of the temperature control object by heater heating It is preferable to do.

  According to the printed circuit board temperature control method of the present invention, even if the operation and stop of the printed circuit board are repeated, the thermal stress accompanying the heat generation of the semiconductor device or the like is not applied to the joint between the printed circuit board and the semiconductor device or the like, Alternatively, the lifetime is not reduced due to small thermal stress, and the long-term reliability of the printed circuit board is improved. If a temperature measuring device such as a thermistor is provided, the temperature can be controlled with higher accuracy. Generally, in the printed circuit board, the temperature change due to heat generation is severe at the start of the operation of the printed circuit board, and therefore it is preferable that the temperature control at the start of the operation can be performed. The temperature control at the start of the operation is a temperature control including a preheating time just before the printed circuit board is actually operated. In the preheating control, accurate and effective control can be performed by controlling by the preheating time or by controlling the temperature of the temperature control object. Moreover, the temperature control by the heater and the power supply control device for the heater is a temperature control method that is simple, highly accurate, and highly reliable.

  According to the present invention, a semiconductor device and a printed circuit board having improved durability and reliability by preventing deterioration due to thermal distortion of a semiconductor device due to heat generation of a heat-generating component such as a semiconductor chip and a printed circuit board on which the semiconductor device is mounted, and a semiconductor A temperature control method for improving durability and reliability of the apparatus and the printed circuit board can be provided.

Next, the best mode for carrying out the present invention will be described with reference to the drawings.
(Embodiment 1)
A semiconductor device of the present invention will be described as Embodiment 1 with reference to FIG. FIG. 1 shows an example of a semiconductor device of the present invention as a cross-sectional view. The semiconductor device 1 in FIG. 1 has a semiconductor chip 3 mounted on a semiconductor substrate 2 in the same manner as a normal semiconductor device, and a heat dissipation member 4 is in close contact with the back surface (side without a connection electrode) of the semiconductor chip 3. ing. The heat radiating member 4 is in close contact with the semiconductor substrate 2 so that the space for housing the semiconductor chip 3 is sealed. The heat radiating member 4 has a function of suppressing a temperature rise due to heat generated by the operation of the semiconductor chip 3. The heat radiating member 4 is in close contact with the semiconductor chip 3 to improve heat conduction from the semiconductor chip 3. A metal material having good thermal conductivity is used to facilitate heat dissipation to the outside of the semiconductor device. In this semiconductor device, ball electrodes 8 and 9 are used as a connection electrode between the semiconductor chip 3 and the semiconductor substrate 2 and a connection electrode between the semiconductor device 1 and an external printed circuit board.

  In the semiconductor device 1, heaters 5 a, 5 b, and 5 c are incorporated in the semiconductor substrate 2, the semiconductor chip 3, and the heat dissipation member 4, respectively. The heaters may be arranged not on the inside but on the surface, but it is often more effective to arrange the heater inside. The heaters 5a and 5c are preferably arranged at positions close to the semiconductor chip 3. This is because the semiconductor chip 3 is a heat generating part of the semiconductor device, so that the vicinity of the semiconductor chip 3 is a part where the temperature change is severe and the temperature control is sufficient.

In this semiconductor device 1, FIG. 4 shows the amount of elongation calculated from the temperature change of the semiconductor chip 3 and the semiconductor substrate 2 when the semiconductor chip 3 is energized and started to operate, and the temperature rise at that time. In FIG. 4, the graph on the right side represents the temperature change of each member with respect to the time from the start of operation of the semiconductor chip 3. The graph on the left represents the amount of elongation calculated from the coefficient of thermal expansion with respect to the temperature of each member. Here, the curve (a) is a graph of the semiconductor chip 3, and the curves (b) and (b ′) are graphs of the semiconductor substrate 2. If, when starting the operation by energizing the semiconductor chip 3 of the semiconductor device 1 without temperature control, the temperature of the semiconductor chip 3, the reference point O along the graph (a) between the start operation time t ₁ It rises from up to _{T 1.} The semiconductor chip 3 is calculated to increase by l ₁ as the temperature rises to the temperature T ₁ . On the other hand, the temperature of the semiconductor substrate 2 rises from the reference point O to the temperature T ₂ along the graph (b) during the time t ₁ due to heat transfer from the semiconductor chip 3 and heat dissipation to the outside of the semiconductor device. The semiconductor substrate 2 is calculated to increase by l ₂ as the temperature rises to the temperature T ₂ .

If the elongation amounts l ₁ and l ₂ are equal, the semiconductor chip 3 and the semiconductor substrate 2 connected by the ball electrode (also referred to as a bump electrode) 8 exhibit the same elongation, and thermal stress is generated in each member. do not do. However, in reality, the semiconductor chip 3 and the semiconductor substrate 2 have different temperature rise curves and thermal expansion curves, so that the elongations l ₁ and l ₂ are rarely equal as shown in FIG. Therefore, stress for adjusting the difference between the elongation amounts l ₁ and l ₂ is generated at the joint portion between the semiconductor chip 3 and the semiconductor substrate 2. If the semiconductor device is repeatedly activated and stopped, and the joint is repeatedly stressed, the ball electrode portion having the weakest joint may be damaged.

Therefore, in the semiconductor device 1 of the present invention, the thermistors 5a, 5b, and 5c, which are temperature control devices built in the respective members, control the temperature of each member at the start of the operation of the semiconductor device 1, thereby providing the semiconductor device. The difference in the amount of elongation between the members at the start of the operation of 1 is eliminated or reduced. For example, in order to eliminate the difference in elongation between the semiconductor chip 3 and the semiconductor substrate 2, the elongation l ₂ of the semiconductor substrate 2 may be set equal to l ₁ as shown in FIG. For this purpose, the temperature of the semiconductor substrate 2 at time t ₁ may be set as T ₃ . Measured in advance an initial temperature T ₄ to a temperature of the semiconductor substrate 2 is T ₃ during the time t _1, before activating by applying power to the semiconductor chip 3, by preheating the semiconductor substrate 2 there is a temperature control method to keep the temperature T _4. Further, it is only necessary to include a temperature control device that controls the heater disposed on the semiconductor substrate 2 to increase the temperature before the operation of the semiconductor chip 3.

  In the above description, only the temporary point has been described. However, the semiconductor device 1 is applied by applying the above-described concept based on the temperature change of the semiconductor substrate 2 due to heat generation of the semiconductor chip 3 and the thermal expansion characteristics of the semiconductor chip 3 and the semiconductor substrate 2. The stress due to the difference in thermal expansion between the semiconductor chip 3 and the semiconductor substrate 2 can be reduced by finely controlling the temperature for each time from the start of the operation to the steady state.

  Furthermore, a method for reducing the thermal stress as described above by simple temperature control is illustrated. In FIG. 5, the semiconductor substrate 2 is preheated before the semiconductor chip 3 is operated, and when the semiconductor substrate 2 is preheated to 60 ° C., the semiconductor substrate 2 is heated even after the semiconductor chip 3 is operated. The temperature of the semiconductor substrate 2 is controlled to 70 ° C. when the semiconductor chip 3 is stabilized at about 90 ° C. In this example, it is assumed that the elongation due to the thermal expansion of the semiconductor chip 3 at 90 ° C. and the elongation due to the thermal expansion of the semiconductor substrate 2 at 70 ° C. are substantially the same. In this way, the stress due to the difference in thermal expansion between the semiconductor chip 3 and the semiconductor substrate 2 can be made small. In particular, since the thermal stress is small in a high temperature range, the ball electrode 8 portion, which is a joint portion of the semiconductor chip 3 and the semiconductor substrate 2, is suitable because the stress does not act (or is small) at high temperatures when the strength decreases.

  FIG. 6 shows an example of temperature control when the material of the semiconductor substrate 2 is different and the coefficient of thermal expansion is close to that of the semiconductor chip 3. In this case, the elongation of the semiconductor substrate 2 due to thermal expansion is relatively small, and the temperature of the semiconductor substrate 2 is controlled to 85 ° C. in order to generate the same elongation as that of the semiconductor chip 3 due to thermal expansion at 90 ° C. .

  In FIG. 1, heaters 5 b and 5 c for temperature control are also arranged on the semiconductor chip 3 and the heat radiating member 4. Regarding the heat radiating member 4, in addition to adjusting the amount of elongation due to thermal expansion at the bonding surface with the semiconductor chip 3, the stress at the joint between the semiconductor substrate 2 and the heat radiating member 4 due to the difference in the amount of elongation with the semiconductor substrate 2. It can also be used to reduce this. In particular, the heat dissipating member 4 has excellent heat dissipating properties, so that when the semiconductor chip 3 stops operating and does not generate heat, it is rapidly cooled. At that time, the difference in elongation due to the temperature difference between the semiconductor substrate 2 and the semiconductor chip 3 or the semiconductor substrate 2 becomes large, which is likely to cause stress, and can be adjusted.

  In the semiconductor device of the present invention, temperature measurement devices such as thermistors 6a and 6c are arranged on the respective members for direct temperature measurement as more direct control as well as temporal program control of the heater heat generation amount. Each member may be controlled to have a predetermined temperature. The temperature measurement by the temperature measuring device can also be used for the temporal program control of the heater heat generation amount.

(Embodiment 2)
A printed circuit board according to the present invention will be described as a second embodiment with reference to FIGS. In FIG. 3, an example of the printed circuit board of this invention was shown as a fragmentary sectional view. The printed circuit board 11 in FIG. 3 has a semiconductor device 1, other electronic components 12, an electrical component 13, and the like mounted on the printed circuit board 10 in the same manner as a normal printed circuit board. The semiconductor device 1 includes a VLSI, LSI, IC, and the like, and other electronic components 12 and electrical components 13 include transistors, resistors, capacitors, and the like. The printed circuit board 11 uses ball electrodes 8 and 9 as connection electrodes between the printed circuit board 10 and the semiconductor device 1 or the like.

  In the printed circuit board 11 according to the second embodiment, temperature control of the printed circuit board 10, the semiconductor device 1, and other electronic components 12 and electrical components 13 as necessary, such as heaters 5a, 5d, 5e, 5f, 5g, and 5h. The device is arranged. The heaters 5a, 5d, 5e, 5f, 5g, and 5h may be arranged on the surface of each component such as the semiconductor device 1, but it is often more effective to arrange them inside. The heaters 5d, 5e, and 5f arranged on the printed circuit board 10 are preferably arranged at positions close to components such as the semiconductor device 1 from the viewpoint of temperature control of the printed circuit board 10. These temperature control heaters 5a, 5d, 5e, 5f, 5g, and 5h are caused by a temperature difference between the printed circuit board 10 and the semiconductor device 1 and other electronic components 12 and electrical components 13 when the printed circuit board 11 is operated. It becomes easy to operate in order to relieve the thermal stress. Although not shown, examples of the temperature control target include members having a joint portion that is joined to the printed board 10 such as a reinforcing part, a heat radiating part, and a protective part of the printed board 10 and generates thermal stress.

  The effect of the heater on the thermal stress between the printed circuit board 10 and the semiconductor device 1 and other electronic components 12 and electrical components 13 is the same as that of the printed circuit board 10 and the semiconductor device 1. 2 is the same, the case of the printed circuit board 10 and the semiconductor device 1 considered to have the largest amount of heat generation and the greatest thermal stress will be described as an example with reference to FIG.

In FIG. 2, as an example of a simple printed circuit board 11, a highly integrated semiconductor device 1 that generates a large amount of heat during operation is mounted on a printed circuit board 10. The graph shown in FIG. 4 explains the amount of elongation calculated from the temperature change of the semiconductor device 1 and the printed circuit board 10 and the temperature rise at that time when the printed circuit board 10 is energized and starts operating as an electronic device. To do. In FIG. 4, the graph on the right side represents the temperature change of the semiconductor device 1 and the printed board 10 with respect to the operation time of the printed circuit board 11. The graph on the left represents the amount of elongation calculated from the coefficient of thermal expansion with respect to the temperature of each member. Here, the member (a) is a graph of the semiconductor device 1, and the members (b) and (b ′) are graphs of the printed circuit board 10. If the printed circuit board 11 and the semiconductor device 1 are energized to start operation without controlling the temperature of the printed circuit board 10 and the semiconductor device 1, the temperature of the semiconductor device 1 is a reference along the graph (a) during the time t _1. to rise from the point O to _{T 1.} Then, the semiconductor device 1 is calculated to increase by l ₁ due to thermal expansion with the temperature T ₁ . On the other hand, the temperature of the printed circuit board 10 rises from the reference point O to T ₂ along the graph (b) during time t ₁ due to heat transfer from the semiconductor device 1 and heat dissipation to the outside of the printed circuit board 10. The semiconductor substrate 2 is calculated to grow by l ₂ with the temperature T ₂ .

If the elongation amounts l ₁ and l ₂ are equal, the semiconductor device 1 and the printed circuit board 10 connected by the ball electrode exhibit the same elongation, and no thermal stress is generated in each member. However, in reality, the semiconductor device 1 and the printed circuit board 10 have different temperature rise curves and thermal expansion curves, so that the elongation amounts l ₁ and l ₂ are rarely equal as shown in FIG. Therefore, a stress for adjusting the difference between the elongation amounts l ₁ and l ₂ is generated in the joint portion between the semiconductor device 1 and the printed circuit board 10. If the printed circuit board 11 is repeatedly actuated and stopped, and the joint is repeatedly stressed, the weakest ball electrode portion of the joint may be damaged.

Therefore, in the printed circuit board 11 of the present invention, the temperature control device incorporated in each member controls the temperature of each member when the operation of the printed circuit board 11 is started, and the semiconductor device 1 is started when the operation is started. Eliminate or reduce the difference in elongation due to thermal expansion between each member in the temperature raising process. For example, in order to eliminate the difference in expansion amount between the semiconductor device 1 and the printed circuit board 10, as shown in FIG. 4, them to elongation of l ₂ of the printed circuit board 10 the same as the elongation amount l ₁ of the semiconductor device 1 That's fine. For this purpose, the temperature of the printed circuit board 10 may be Shiteyare and T _3. Before the temperature of the printed circuit board 10 becomes T ₃ during the time t ₁ , the initial temperature T ₄ is measured in advance, and the printed circuit board 11 or the semiconductor device 1 is operated by applying power to the printed circuit board 11. 10 to preheat the there is a temperature control method to keep the temperature T _4. The heater 5d disposed on the printed circuit board 11 may be provided with a temperature control device that controls the temperature of the heater 5d before the semiconductor device 1 is activated.

  In the above description, although only a temporary point has been described, a printed circuit board is applied by applying the above concept based on the temperature change of the printed circuit board 10 due to heat generation of the semiconductor device 1 and the thermal expansion characteristics of the semiconductor device 1 and the printed circuit board 10. The stress caused by the difference in thermal expansion between the printed circuit board 10 and the semiconductor device 1 can be reduced by finely controlling the temperature for each time from the start of operation 11 to the steady state.

  Further, a method for reducing the above-described thermal stress by simple temperature control will be described. In FIG. 5, the printed circuit board 11 is preheated before the semiconductor device 1 is operated. When the printed circuit board 11 is preheated to 60 ° C., the printed circuit board 11 is also operated after the semiconductor device 1 is operated. And the temperature of the printed circuit board 11 is controlled to 70 ° C. when the semiconductor chip 3 is stabilized at about 90 ° C. In this example, the semiconductor chip 3 of the semiconductor device 1 has a temperature of 90 ° C., and the entire semiconductor device 1, particularly the portion of the semiconductor substrate 2 bonded to the printed circuit board 11 has a temperature of 70 ° C. The overall elongation due to thermal expansion and the elongation due to thermal expansion of the printed circuit board 11 are substantially the same. In this way, the stress due to thermal expansion of the semiconductor device 1 and the printed circuit board 11 can be made little or small. In particular, since the thermal stress on the ball electrode 9 which is a joint portion is small in a high temperature range, the stress does not act (or is small) at a high temperature when the strength of the ball electrode portion is reduced.

  FIG. 6 shows an example of temperature control when the printed circuit board 11 and the semiconductor substrate 2 are made of different materials and have a thermal expansion coefficient close to that of the semiconductor device 1 as in the case of the ceramic semiconductor substrate 2. In this case, the elongation due to thermal expansion of the semiconductor substrate 2 is relatively small, and the temperature of the semiconductor substrate 2 is controlled to 85 ° C. in order to generate substantially the same elongation as the thermal expansion of the semiconductor device 1 at 90 ° C. The printed circuit board 11 is set to 70 ° C. In this way, the printed circuit board 11 and the semiconductor substrate 2 have the same amount of elongation due to thermal expansion, and no thermal stress is generated at the joint portion of the ball electrode 9.

  In the printed circuit board 11 shown in FIG. 2, in the semiconductor device 1, as described in the semiconductor device of the first embodiment, the semiconductor chip 3 and the heat radiating member 4 are also provided with temperature control heaters 5b and 5c. . Since these functions and operations have already been described in the semiconductor device of the first embodiment, a description thereof will be omitted.

  In the semiconductor device of the present invention, temperature measurement devices such as thermistors 6a, 6c, and 6d are arranged on the respective members for direct control as well as temporal program control of the heating value of the heater. The heater heating value may be controlled so that each member has a predetermined temperature. The temperature measurement by the temperature measuring device can also be used for temporal program control of the heater.

  FIG. 3 shows a partial cross-sectional view of a printed wiring board 11 in which an electronic component 12 and an electrical component 13 are mounted on the printed board 10 in addition to the semiconductor device 1. The semiconductor device 1, the electronic component 12, and the electrical component 13 are joined to the printed wiring board 11 by ball electrodes 9a, 9b, and 9c. The distinction between the electronic component 12 and the electrical component 13 is not strict, and components mounted on the printed wiring board 11 such as transistors, resistors, capacitors, switches, and relays are collectively referred to as the electronic component 12 and the electrical component 13.

  Heaters 5d, 5e, 5f are arranged on the printed circuit board 10. Heaters 5a, 5g, and 5h are also disposed in the semiconductor device 1, the electronic component 12, and the electrical component 13. Although not shown, the amount of heat generated in each of the heaters 5a, 5d, 5e, 5f, 5g, and 5h is controlled by a supply power supply control device. For the supply power control, various control methods such as power supply time control, supply power amount control, on / off control, program control, and temperature control can be employed. Moreover, it is preferable that a temperature measuring device is disposed on each heating target component of the printed circuit board 10, the semiconductor device 1, the electronic component 12, and the electrical component 13. The temperature of the heating target component can be measured by the temperature measuring device, and the heater can be easily controlled to reach a desired temperature.

  Such a printed wiring board 11 has a large temperature difference between the semiconductor device, the electronic component, the electric component and the printed wiring board 11 when a part of the operation is stopped at the start of the operation. May occur. Even in such a case, each of the heaters operates to reduce the temperature difference between the semiconductor device, the electronic component, the electrical component, and the printed wiring board 11. By relaxing the temperature difference, the thermal stress acting on the ball electrodes 9a, 9b, 9c can be relaxed, and damage due to the thermal stress can be prevented. In particular, it is possible to prevent long-term reliability deterioration of the ball electrodes 9a, 9b, and 9c due to repeated thermal stress.

(Embodiment 3)
A semiconductor device temperature control method according to the present invention will be described as a third embodiment. A semiconductor device according to the present invention includes a semiconductor substrate, a semiconductor chip disposed on the semiconductor substrate, and a heat dissipation member that dissipates heat generated by the semiconductor chip, and the semiconductor device includes the semiconductor substrate, the semiconductor chip, and the heat dissipation member. This is a temperature control method for controlling at least one temperature. In particular, the temperature control method is capable of preheating control of an object to be temperature controlled so as to reduce thermal distortion of the semiconductor device due to heat generation of the semiconductor chip at the start of operation of the semiconductor device.

  FIG. 7 shows a flow of a temperature control method by the temperature control device provided in the semiconductor device. Referring to FIG. 7, when the main power supply of the entire electronic device including the semiconductor device is turned on to start up the device (step S1), the heater control device is turned on (step S2), and the heater built in the semiconductor device is turned on. It operates and each part of the semiconductor device reaches a set temperature (step S3). In this case, as already described in the first embodiment, it is preferable to control the temperature in the vicinity of the junction between the semiconductor substrate and the semiconductor chip. When the semiconductor device reaches a predetermined temperature, the semiconductor device is turned on to actually operate the semiconductor device (step S4). When the semiconductor device is activated, the semiconductor chip generates heat, and the temperature of the semiconductor device increases rapidly around the semiconductor chip to reach a steady state. In this case, since the portion that is not the heat generating portion including the semiconductor substrate has been warmed up to a predetermined temperature in advance, the temperature difference from the semiconductor chip does not increase when the temperature is raised. For this reason, for example, a difference in thermal expansion hardly occurs between the semiconductor chip and the semiconductor substrate. In other words, since no thermal stress is generated in the electrode portion such as the bump electrode that joins the semiconductor chip and the semiconductor substrate in the temperature rising process of the semiconductor device, the occurrence of defective bonding of the electrode due to the thermal stress can be suppressed, and the semiconductor device Reliability is improved.

  When stopping the semiconductor device, it is determined whether or not the power source of the entire electronic device including the semiconductor device must be stopped (step S5). For example, at the time of maintenance of only the semiconductor device, only the power source of the semiconductor device is stopped, the heater control device is set in an operating state, and the semiconductor device is set in a warm-up state (step S6). When the maintenance of the semiconductor device is completed, the semiconductor device is turned on and operated (step S4). In this way, the semiconductor device is maintained at a predetermined temperature as in the case of starting up the entire electronic device. Even if the semiconductor device is operated with the power on, the semiconductor substrate and the like can be The temperature difference between the non-heat generating part and the semiconductor chip does not increase. And the generation | occurrence | production of the joining defect of the electrode by a thermal stress is suppressed.

  In (Step S5), when the power supply of the entire electronic device including the semiconductor device must be stopped, the power supply of the entire electronic device is turned off (Step S7). Then, the entire electronic device including the temperature control device is stopped.

  As a temperature control method, heating control with a heater can be preferably applied. For heating control, program control of the power supplied to the heater, temperature rise program control for controlling the power supplied to the heater from the difference between the measured temperature of the member to be heated and the temperature rise program, and supply of power to the heater for a predetermined time Existing heating control methods such as heating time control can be adopted.

(Embodiment 4)
A temperature control method for a printed circuit board according to the present invention will be described as a fourth embodiment. This embodiment is similar to the temperature control method for a semiconductor device described in the third embodiment. The semiconductor chip in the temperature control method of the semiconductor device is replaced with the semiconductor device in the temperature control method of the printed circuit board, or other electronic component or electric component that generates heat during operation, and the semiconductor substrate in the temperature control method of the semiconductor device is printed. The circuit board temperature control method may be considered as a printed circuit board. And the temperature control method of the printed circuit board of Embodiment 4 is joining by the thermal stress of the ball electrodes 9, 9a, 9b, 9c which hits the junction part of the printed circuit board 10 and the semiconductor device 1 etc. which were shown in FIG. Can prevent damage.

  The specific temperature control method is the same as the temperature control method of the semiconductor substrate described in the third embodiment using the heater and the control device disposed on the printed circuit board in the printed circuit board described in the second embodiment. The temperature may be controlled as described above.

Regarding the above description, the following items are further disclosed.
(Appendix 1)
A semiconductor device comprising: a semiconductor substrate provided with a temperature control device; a semiconductor chip disposed on the semiconductor substrate; and a heat radiating member that radiates heat generated by the semiconductor chip (Appendix 2)
The semiconductor device according to appendix 1, wherein at least one of the semiconductor chip and the heat dissipation member includes a temperature control device.
(Appendix 3)
The semiconductor device according to appendix 1 or 2, wherein the temperature control device includes a heater and a power supply control device for the heater.
(Appendix 4)
4. The semiconductor device according to any one of appendices 1 to 3, wherein the temperature control device includes a temperature measuring device.
(Appendix 5)
The temperature measuring device preheat-controls the temperature control object so as to reduce thermal distortion of the semiconductor device due to heat generation of the semiconductor chip at the start of operation of the semiconductor device. Semiconductor device.
(Appendix 6)
6. The semiconductor device according to appendix 5, wherein the temperature measuring device preheats the temperature control object for a predetermined time.
(Appendix 7)
The semiconductor device according to appendix 5 or 6, wherein the temperature measuring device preheats the temperature control object when the temperature control object is equal to or lower than a predetermined temperature.
(Appendix 8)
The semiconductor device according to any one of appendices 5 to 7, wherein the temperature measuring device preheats until the temperature control object exceeds a predetermined temperature.
(Appendix 9)
A printed circuit board comprising the semiconductor device according to any one of appendices 1 to 8 mounted on a printed board including a temperature control device.
(Appendix 10)
The printed circuit according to appendix 9, wherein at least one of an electronic component, an electrical component, a printed circuit board reinforcing component, a heat radiating component, and a printed circuit board protection component mounted on the printed circuit board includes a temperature control device. Circuit board.
(Appendix 11)
The printed circuit board according to appendix 9 or 10, wherein the temperature control device includes a heater and a power supply control device for the heater.
(Appendix 12)
The printed circuit board according to any one of appendices 9 to 11, wherein the temperature control device includes a temperature measurement device.
(Appendix 13)
The temperature measuring device preheat-controls the temperature control object so as to reduce thermal distortion of the printed circuit board due to heat generation of the semiconductor chip at the start of the operation of the semiconductor device. The printed circuit board as described.
(Appendix 14)
14. The printed circuit board according to appendix 13, wherein the temperature measuring device preheats the temperature control object for a predetermined time.
(Appendix 15)
The printed circuit board according to appendix 13 or 14, wherein the temperature measuring device preheats the temperature control object when the temperature control object is equal to or lower than a predetermined temperature.
(Appendix 16)
The printed circuit board according to any one of appendices 13 to 15, wherein the temperature measuring device preheats until the temperature control object exceeds a predetermined temperature.
(Appendix 17)
Temperature control of a semiconductor device characterized by controlling the temperature of the semiconductor substrate in a semiconductor device comprising a semiconductor substrate, a semiconductor chip disposed on the semiconductor substrate, and a heat dissipation member that dissipates heat generated by the semiconductor chip Method.
(Appendix 18)
18. The temperature control method for a semiconductor device according to appendix 17, wherein the temperature of at least one of the semiconductor chip and the heat dissipation member is controlled.
(Appendix 19)
The temperature control method for a semiconductor device according to appendix 17 or 18, wherein the temperature control object is preheat controlled so as to reduce thermal distortion of the semiconductor device due to heat generation of the semiconductor chip at the start of operation of the semiconductor device.
(Appendix 20)
20. The temperature control method for a semiconductor device according to appendix 19, wherein the temperature control object is preheat controlled for a predetermined time.
(Appendix 21)
The temperature control method for a semiconductor device according to appendix 19 or 20, wherein the temperature control object is preheated when the temperature control object is equal to or lower than a predetermined temperature.
(Appendix 22)
The temperature control method for a semiconductor device according to any one of appendices 19 to 21, wherein the temperature control object is preheated until the temperature exceeds a predetermined temperature.
(Appendix 23)
The temperature control method for a semiconductor device according to any one of appendices 17 to 22, wherein the temperature of the temperature control object is controlled by heating the heater.
(Appendix 24)
Temperature control of a printed circuit board, wherein the temperature of the printed circuit board is controlled in a printed circuit board on which the semiconductor device temperature-controlled by the temperature control method according to any one of appendices 17 to 23 is mounted on the printed circuit board Method.
(Appendix 25)
25. The printed circuit board according to appendix 24, wherein the temperature of at least one of an electronic component, an electrical component, a printed circuit board reinforcement component, a heat dissipation component, and a printed circuit board protection component mounted on the printed circuit board is controlled. Temperature control method.
(Appendix 26)
The temperature of the printed circuit board according to appendix 24 or 25, wherein the temperature control object is preheat controlled so as to reduce thermal distortion of the printed circuit board due to heat generation of the semiconductor chip at the start of operation of the printed circuit board. Control method.
(Appendix 27)
The temperature control method for a printed circuit board according to any one of appendices 24-26, wherein the temperature control object is preheat controlled for a predetermined time.
(Appendix 28)
The temperature control method for a printed circuit board according to appendix 26 or 27, wherein the temperature control object is preheated when the temperature control object is equal to or lower than a predetermined temperature.
(Appendix 29)
29. The temperature control method for a printed circuit board according to any one of appendices 26 to 28, wherein the temperature control object is preheated until the temperature exceeds a predetermined temperature.
(Appendix 30)
The temperature control method for a printed circuit board according to any one of appendices 24-29, wherein the temperature of the temperature control object is controlled by heater heating.

FIG. 1 is a cross-sectional view of a semiconductor device of the present invention. FIG. 2 is a cross-sectional view of a printed circuit board equipped with the semiconductor device of the present invention. FIG. 3 is a cross-sectional view of the printed circuit board of the present invention. FIG. 4 is an adjustment diagram of changes in elongation due to heating by the member. FIG. 5 is a temperature control example (1) of the semiconductor substrate and the printed circuit board. FIG. 6 is a temperature control example (2) of the semiconductor substrate and the printed circuit board. FIG. 7 is a flowchart of temperature control in the temperature control device. FIG. 8 shows a heat cycle test result of the semiconductor device.

Explanation of symbols

1: Semiconductor device 2: Semiconductor substrate 3: Semiconductor chip 4: Heat radiation member 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h: Heater 6a, 6b, 6c, 6d: Thermistor 7a, 7b: Temperature control device 8 : Ball electrode 9: Ball electrode 10: Printed circuit board 11: Printed circuit board 11: Electronic component 12: Electrical component

Claims (10)

  A semiconductor device comprising: a semiconductor substrate provided with a temperature control device; a semiconductor chip disposed on the semiconductor substrate; and a heat dissipating member that dissipates heat generated by the semiconductor chip.   The semiconductor device according to claim 1, wherein the temperature control device includes a heater and a power supply control device for the heater.   The semiconductor device according to claim 1, wherein the temperature control device includes a temperature measurement device.   A printed circuit board comprising the semiconductor device according to claim 1 mounted on a printed board having a temperature control device.   The printed circuit board according to claim 4, wherein the temperature control device includes a heater and a power supply control device for the heater.   The printed circuit board according to claim 4, wherein the temperature control device includes a temperature measurement device.   A temperature of the semiconductor device characterized by controlling the temperature of the semiconductor substrate in a semiconductor device comprising a semiconductor substrate, a semiconductor chip disposed on the semiconductor substrate, and a heat dissipation member that dissipates heat generated by the semiconductor chip. Control method.   8. The temperature control method for a semiconductor device according to claim 7, wherein preheating control of the semiconductor substrate is performed so as to reduce thermal distortion of the semiconductor device due to heat generation of the semiconductor chip at the start of operation of the semiconductor device.   A temperature control method for a printed circuit board, comprising: controlling a temperature of the printed circuit board on a printed circuit board on which the semiconductor device temperature-controlled by the temperature control method according to claim 7 or 8 is mounted. .   The printed circuit board temperature control method according to claim 9, wherein the printed circuit board is preheat controlled so as to reduce thermal distortion of the printed circuit board due to heat generation of the semiconductor chip at the start of operation of the printed circuit board.

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