JPH0645337U - Semiconductor device - Google Patents

Abstract

(57) [Abstract] [Purpose] To increase the current capacity that can be passed without limiting the energizing current due to the difference in the length of the aluminum wire connected by bonding. [Structure] By making the bonding pads 6a and 6b of the emitter electrode on the semiconductor chip 5 and the emitter conductor pattern 30 on the insulating substrate 1 by bonding, the aluminum wire 17 has the same length and the shortest length. Since the amount of heat generated is uniform and minimized, the current capacity that can be passed can be increased as a result.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a semiconductor device having a structure in which an electrode on the upper surface of a semiconductor chip is bonded and connected to a predetermined conductor pattern with an aluminum wire.

[0002]

[Prior art]

 A conventional example of this type of semiconductor device is shown in FIG. FIG. 2 is a plan view showing a part of the semiconductor device. In the figure, reference numeral 1 denotes an insulating substrate, on which a collector conductor pattern 2, an emitter conductor pattern 3 and a gate conductor pattern 4 are arranged. Further, the semiconductor chip 5 is soldered and fixed onto the collector conductor pattern 2. Bonding pads 6a and 6b of the emitter electrode provided on the upper surface of the semiconductor chip 5 and the emitter conductor pattern 3 are bonded by a plurality of aluminum wires 7a and 7b. Similarly, the gate electrode (not shown) on the upper surface of the semiconductor chip 5 and the gate conductive pattern 4 on the upper surface of the insulating substrate 1 are connected by bonding with an aluminum wire 7c.

As the aluminum wires 7a, 7b, 7c, fine wires having a diameter of 1 mmφ or less are generally used, and in a power semiconductor chip, they are connected by a plurality of aluminum wires. Since the bonding pads 6a, 6b of the emitter electrode on the surface of the semiconductor chip 5 are provided at a plurality of places, the aluminum wires 7a, 7b are, for example, a shorter aluminum wire 7b of about 5 mm and a longer aluminum wire 7b. The aluminum wire 7a is about 15 mm. By the way, when the diameter of the aluminum wire is small, the heat generation of the aluminum wire itself greatly changes depending on the connection length of the wire and the value of the current to be passed. This phenomenon will be described with reference to the graph in FIG.

In the graph of FIG. 3, the horizontal axis represents the current value I (A) and the vertical axis represents the temperature rise value ΔT (° C.). In addition, the diameter of the aluminum wire is 0.4 mm, and the length (wiring length) for connecting the conductor patterns is changed from 5 mm to 30 mm, and the wire is bonded and connected. Therefore, when a direct current was changed and passed through each aluminum wire, the temperature rose as in each curve. From this result, it was found that the shorter the connection length of the aluminum wire, the larger the amount of heat radiated through the conductor pattern. For example, comparing the aluminum wire with a length of 5 mm and the aluminum wire with a length of 15 mm, when a current I = 20 A is applied to these aluminum wires, the wire with a length of 5 mm has a temperature rise of about 5 ° C at point b. On the other hand, in the case of 15 mm, the temperature increased to about 70 ° C. at point a.

Looking at the structure of the conventional semiconductor device shown in FIG. 2 in consideration of these actual measurement results, the aluminum wires 7a and 7b connecting the emitter electrode on the upper surface of the semiconductor chip 5 and the emitter conductor pattern 3 are It has been found that the lengths, that is, the connection lengths are different, so that the current that can be passed is limited to the temperature rise of the longer aluminum wire 7a. That is, if the diameter of the conventional aluminum wire is 0.4 mmφ, there is a temperature difference as shown in FIG. 3, and conversely, if the temperature rise ΔT is the same, for example, about 70 ° C. The point shows about 20 A and the point of 5 mm shows about 48 A at the point c, which means that the current capacities are more than doubled.

[0006]

[Problems to be solved by the device]

 In the conventional semiconductor device, since the aluminum wires 7a and 7b that connect the emitter electrode on the surface of the semiconductor chip 5 to the emitter conductor pattern 3 on the insulating substrate have different connection lengths as described above, the longer aluminum wire 7a There was a problem to be solved in that a relatively large current could not flow because the current capacity was limited due to the temperature rise accompanying energization.

[0007]

[The purpose of the device]

 The present invention has been made to solve the above problems, and a semiconductor device capable of increasing a current capacity that can be flowed without limiting an energization current due to a difference in length of an aluminum wire connected by bonding. It is intended to provide

[0008]

[Means for solving problems]

 The semiconductor device of the present invention has a semiconductor chip mounted and fixed to a conductor pattern on an insulating substrate, and a plurality of semiconductor chips are provided between the emitter electrode on the upper surface of the semiconductor chip and the emitter conductor pattern on the insulating substrate. In the semiconductor device that is bonded and connected with the aluminum wire, the emitter conductor patterns are symmetrically arranged on both sides of the semiconductor chip, and the emitter electrode on the upper surface of the semiconductor chip and the emitter conductor pattern have the same length. It is characterized in that it is connected by bonding with a plurality of aluminum wires that are the shortest distance.

[0009]

[Action]

 In the semiconductor device of the present invention, the amount of heat generated is uniform and minimized by making the length of the aluminum wire connecting the emitter electrode on the semiconductor chip and the emitter conductor pattern on the insulating substrate the same and the minimum length. As a result, the current capacity that can be passed can be increased.

[0010]

【Example】

 Hereinafter, an embodiment of the present invention will be described in detail with reference to FIG. In FIG. 1, a collector conductor pattern 2 is formed on an insulating substrate 1 as in the conventional case. Emitter conductor patterns 30 are formed symmetrically with the collector conductor pattern 2 in the center interposed therebetween. A gate conductor pattern 4 is formed above the collector conductor pattern 2 as in the conventional case. A semiconductor chip 5 is mounted and fixed on the collector conductor pattern 2 described above, and bonding pads 6a and 6b for emitter electrodes and bonding pads (not shown) for gate electrodes are formed on the semiconductor chip 5. Are formed. The emitter electrode bonding pads 6a and 6b on the semiconductor chip 5 and the emitter conductor pattern 30 on the insulating substrate 1 are bonded and connected by an aluminum wire 17.

Here, what is important is that the lengths of the aluminum wires 17 are all the same, and the connection length is set to be the shortest distance. In the embodiment of the present invention, the diameter of the aluminum wire was 0.4 mmφ, and all the connection lengths were about 5 mm. The connection by bonding to the gate conductor pattern 4 is the same as the conventional one. The temperature rise in the above embodiment is compared with that of the conventional structure as follows. That is, in the conventional structure, since the connection length of the longer aluminum wire 7a is 15 mm, if the temperature rise value ΔT = 70 ° C., a direct current of I = 20 A can be passed. On the other hand, in the structure of the present invention, since the connection length of the aluminum wire 17 is 5 mm, if the temperature rise value ΔT is the same as the conventional one, it can flow up to DC of I = 48A.

[0012]

[Effect of device]

 As described above, according to the present invention, the emitter conductor patterns are provided symmetrically and the aluminum wire connection from the semiconductor chip surface is made to have the same length and the length is the shortest distance. The amount is uniform and minimized, and as a result, the current capacity that can be passed can be increased.

[Brief description of drawings]

FIG. 1 is a plan view showing a part of a semiconductor device according to an embodiment of the present invention.

FIG. 2 is a plan view showing a part of a conventional semiconductor device.

FIG. 3 is a graph showing a relationship between a temperature rise and an electric current depending on a connection length of an aluminum wire.

[Explanation of symbols]

 1 Insulating Substrate 2 Collector Conductor Pattern 4 Gate Conductor Pattern 5 Semiconductor Chips 6a, 6b Bonding Pad 17 Aluminum Wire 30 Emitter Conductor Pattern

Claims (1)

[Scope of utility model registration request] 1. A semiconductor chip mounted and fixed to a conductor pattern on an insulating substrate, wherein a plurality of aluminum wires are provided between the emitter electrode on the upper surface of the semiconductor chip and the emitter conductor pattern on the insulating substrate. In a bonded semiconductor device, emitter conductor patterns are symmetrically arranged on both sides of the semiconductor chip, and an emitter electrode on the upper surface of the semiconductor chip and the emitter conductor pattern have the same length and the shortest distance. A semiconductor device having a plurality of aluminum wires bonded and connected.