JPH10223679A - Manufacture of semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device which can change a specific circuit function without increasing the cost of manufacture. SOLUTION: This semiconductor device comprises a circuit which senses the short circuit at least between two pad patterns adjacently formed on a chip 3 so that the pad patterns may be electrically short circuited by a wire bonding 6 and which changes operating functions in accordance with the above- mentioned sensing of the short circuit. The semiconductor device is manufactured by adjacently forming at least two pad patterns on the chip 3, and by a wire bonding operation, where the two pad patterns are short circuited using the bonding wire 6, is conducted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor device (semiconductor device) and a method for manufacturing the same.

[0002]

2. Description of the Related Art When manufacturing a semiconductor chip, it is necessary to conduct a test to confirm whether the manufactured semiconductor chip operates properly. In some cases, a test circuit is incorporated in a semiconductor chip for the test.
Since a test circuit is not necessary for a semiconductor device as a product after the test is completed, if the user accidentally uses the test circuit and serious damage may be caused, the user is required to comply with the product specification. It is common to specify that use of the test circuit is prohibited.

[0003]

However, since it is often insufficient to specify the prohibition in the standard, it is sometimes necessary to forcibly disable the use of hardware. For example, after the test is completed, a fuse provided in advance is blown to make the test circuit function inactive,
In some cases, laser trimming is performed before packaging with a mold so that a specific function does not operate. However, forcibly disabling the use of such hardware has a problem of increasing the manufacturing cost.

[0004] This means that, regardless of the test circuit of the semiconductor chip, when the product is shipped as a product after completion of manufacture, for example, the user loses unnecessary operation functions in order to reduce power consumption while leaving only necessary operation functions. The same applies to the case where the user wants to make it. Therefore, an object of the present invention is to provide a semiconductor device and a manufacturing method capable of changing a specific operation function without substantially increasing the manufacturing cost.

[0005]

According to the present invention, there is provided a semiconductor device comprising:
At least two pad patterns formed adjacently on the chip so as to be electrically short-circuited by wire bonding, detecting means for detecting a short circuit between the at least two pad patterns, and detecting the short circuit by the detecting means. And a circuit for changing an operation function.

A method of manufacturing a semiconductor device according to the present invention is characterized in that at least two pad patterns are formed adjacently on a chip, and wire bonding for electrically shorting the at least two pad patterns with bonding wires is performed. And

[0007]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows the surface of a semiconductor chip, in which a conductor pattern 1 is formed on the surface of a chip 2. The conductor pattern 1 is a common line, and includes a probe pad 3 and a bonding pad 4. The probe pad 3 serves as a probe (not shown) in a probe test after a wafer process in a semiconductor chip manufacturing process.
Is the part to which the tip of is applied. The test circuit 5 is used for the test. Bonding pad 4
Is an electrode portion to which the bonding wire 6 is connected for connection with an external terminal of the package. As shown in the figure, the bonding pad 4 has a quadrangular ring shape and a partially cut outer shape, and has a space portion 4a communicating with the outside in a central portion. A metal pad 7 made of a conductor member is formed in the space 4a in a state of being electrically non-contact with the bonding pad 4. The metal pad 7 is formed integrally with the lead pattern 8 on the surface of the chip 2, and the lead pattern 8 extends outside the bonding pad 4 via an annular cut portion.

[0008] The lead pattern 8 is connected to a level detection circuit 11. The level detection circuit 11 is short-circuit detection means, and includes a resistor 12 and an inverter 13. The resistor 12 and the inverter 13 are actually formed on the chip 2 as a circuit pattern, but are shown here as circuit symbols for easy understanding. The voltage Vdd is applied to one end of the resistor 12, and the other end is connected to the lead pattern 8 and the input of the inverter 13. The inverter 13 inverts the input level and outputs the result. The output signal of the inverter 13 is supplied to the test circuit 5 described above. Test circuit 5 is in an active state where the test operation can be performed when the output level of inverter 13 is low, and in an inactive state where the test operation cannot be performed when the output level of inverter 13 is high.

A test of a semiconductor chip is performed before wire bonding is performed, and a test circuit 5 is used in the test. A probe is applied to the probe pad 3 to extract operation data of the semiconductor chip by an external measuring device. In this test, since the voltage Vdd is supplied to the input of the inverter 13 via the resistor 12, the input level is high,
The output level of the inverter 13 becomes low. The test circuit 5 is activated by this low level.

After the test of the semiconductor chip is completed, wire bonding is performed, and the bonding pad 4 and the metal pad 7 are electrically connected. That is, wire bonding is performed to obtain electrical connection between the conductor pattern 1 and an external ground or circuit via an external terminal (not shown) of the package. As described above, for example, the tip of the bonding wire 6 made of gold is a bonding ball 16, and the bonding ball 16 is bonded to the bonding pad 4 including the metal pad 7 by a thermocompression bonding method such as a ball bonding method. As a result, the bonding pad 4 and the metal pad 7 are electrically short-circuited by the bonding ball 16 which is thermocompression-bonded. The other end of the bonding wire 6 is connected to an external terminal of the package.

After wire bonding to such a semiconductor chip is performed, packaging is performed. When the user uses the semiconductor device as such a packaged product, the external terminals of the package are grounded, whereby the potential of the conductor pattern 1 including the metal pad 7 and the bonding pad 4 is grounded. It is equal to the potential. Therefore, the voltage Vdd
Is applied to the resistor 12 via another external terminal (not shown), the input of the inverter 13 is at the ground potential, that is, low level.
Output level is high. As a result, the test circuit 5 becomes inactive, and the test circuit 5 does not operate when the user uses the semiconductor device.

In the above-described embodiment, the test circuit is changed from the active state to the inactive state in which the test circuit does not operate after the wire bonding. However, the operation function may be simply changed. That is, for example, instead of prohibiting all the operations of the test circuit, some of the operations may be performed after wire bonding.
It is also effective when it is desired to change the circuit function of not only the test circuit but also other circuits.

Further, in the above embodiment, the metal pad 7 is formed so as to be surrounded by the bonding pad 4. However, if the bonding pad 4 and the metal pad 7 can be short-circuited by the bonding ball 16 during wire bonding. The bonding pad 4 and the metal pad 7 may have any shape pattern.
For example, the bonding pads 4 may be formed so as to be surrounded by the metal pads 7, or the bonding pads 4 may have a shape in which rectangular lands are juxtaposed. Further, the number of pad patterns short-circuited by wire bonding is not limited to two, and three or more pad patterns may be used.

[0014]

As described above, according to the present invention, a specific circuit function can be changed with almost no increase in manufacturing cost.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

[Description of Signs of Main Parts]

 DESCRIPTION OF SYMBOLS 1 Conductor pattern 2 Chip 3 Probe pad 4 Bonding pad 5 Test circuit 6 Bonding wire 7 Metal pad 8 Lead pattern 11 Level detection circuit

Claims (6)

[Claims] 1. At least two pad patterns formed adjacently on a chip so as to be electrically short-circuited by wire bonding, detecting means for detecting a short circuit between the at least two pad patterns, and the detecting means A circuit for changing an operation function in response to detection of a short circuit. 2. One of the at least two pad patterns is a part of a common line to be at a ground potential,
2. The semiconductor device according to claim 1, wherein the other of said two pad patterns is connected to an input of said detecting means. 3. The one pad pattern is formed in a partially cut annular shape, and the other pad pattern is located inside the annular shape, and the other pad pattern is positioned through an annular cut portion of the one pad pattern. 3. The semiconductor device according to claim 2, wherein a lead pattern connected to the pad pattern extends outside the one pad pattern. 4. The semiconductor device according to claim 1, wherein the circuit for changing the operation function is a test circuit for testing an operation of a semiconductor chip in the device. 5. The semiconductor device according to claim 1, wherein the tip of the bonding wire for the wire bonding has a ball shape enough to cover the at least two pad patterns. 6. A method of manufacturing a semiconductor device, comprising: forming at least two pad patterns adjacent to each other on a chip; and performing wire bonding for electrically short-circuiting the at least two pad patterns with bonding wires.