JP2924933B2 - Storage circuit device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a storage circuit provided with a program circuit having a simplified circuit configuration for storing information as to whether or not a defective bit can be remedied in a device mainly obtained by an attached redundant circuit. The present invention relates to a device (memory chip).

[0002]

2. Description of the Related Art Conventionally, many storage circuit devices (memory chips) of this type have a redundant circuit with an increase in memory chip size. Such memory chips are arranged on a silicon wafer in a plurality of units, and an inspection is performed to determine whether they are non-defective or defective. When confirming the quality, the above-mentioned redundant circuit is used for preliminary measurement as a remedy. It is general that the result of the preliminary inspection by the redundant circuit is an initial evaluation for judging a good or defective memory chip.

FIG. 4 shows an inspection procedure using a redundant circuit of a storage circuit device. In the quality inspection, first, a probe is connected to a bonding type pad on a memory chip, and a preliminary measurement (step S1) is performed. In this preliminary measurement (step S1), it is determined whether or not the repair can be performed by the redundant circuit, and based on the result of the determination, the fuse cutting position is determined so that the defective bit is switched to the redundant bit when a defective bit is selected. Things. These determinations or decisions are made for all the memory chips on the silicon wafer.

Next, a trimming (step S2) process for cutting the corresponding fuse based on the determination result is performed. Finally, for all the memory chips on the silicon wafer, as in the preliminary measurement (step S1), a probe is applied to the bonding-applied pad to determine whether the memory chip is a non-defective product or a defective product (step S3). )I do. As a result, defective products are managed by marking them with ink or laser.

[0005] After the above processing, when assembling, by assembling using only the unmarked memory chips, it is possible to assemble using only good memory chips.

[0006]

By the way, recently, as the memory capacity increases, the measurement unit time required for one memory chip has become considerably longer. In addition, in the inspection procedure on the silicon wafer as described above, it is troublesome to perform a total of two measurements of the preliminary measurement and the Pass / Fail measurement for each of the memory chips.

In such a situation, for example, the number of sheets measured by a single silicon wafer per month is greatly reduced. As a result, the number of shipped storage circuit devices is limited.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and a technical problem thereof is to provide a redundant circuit and a simple configuration which can greatly reduce the measurement time in quality inspection on a silicon wafer. And a storage circuit device provided with the program circuit.

[0009]

According to the present invention, there is provided a storage circuit device having a program circuit for storing information as to whether or not a defective bit can be remedied in a device obtained by an attached redundant circuit. The circuit includes a local portion in which a pad, a fuse, and a resistor of a probe stand application type are connected in series in this order, and the other end of a diode having one end connected to a power supply included in the device is connected to the resistor side in the local portion. Is obtained.

Further, according to the present invention, in a storage circuit device provided with a program circuit for storing information as to whether or not a defective bit can be remedied in a device obtained by an attached redundant circuit, the program circuit includes a bonding circuit. A storage circuit device configured by connecting a fuse between an applicable pad and an input protection circuit is obtained.

Further, according to the present invention, in a storage circuit device provided with a program circuit for storing information as to whether or not a defective bit can be remedied in a device obtained by an attached redundant circuit, the program circuit comprises a resistor. And a fuse connected in series, thereby obtaining a storage circuit device in which both ends of a local portion are connected by a probe stand applicable pad.

In addition, according to the present invention, in a storage circuit device provided with a program circuit for storing information as to whether or not a defective bit can be remedied in a device obtained by an attached redundant circuit, the program circuit comprises: A storage circuit device is obtained in which one end of a local portion formed by connecting a resistor and a fuse in series is connected by a probe stand application type pad and the other end is connected by a bonding application type pad.

[0013]

The storage circuit device according to the present invention simplifies the circuit configuration of a program circuit for storing information as to whether a defective bit obtained by a redundant circuit can be remedied at the time of preliminary measurement (specifically, the program circuit has The circuit configuration includes a local part in which a pad, a fuse, and a resistor are applied in series in this order, and a diode whose one end is connected to a power supply included in the device is connected to the resistance side in the local part. Constructed, constructed by connecting a fuse between the bonding-applied pad and the input protection circuit, and connected to a probe stand-applied pad at both ends of a local unit consisting of resistors and fuses connected in series. Or one end of a local part formed by connecting a resistor and a fuse in series, with one end connected by a probe stand applicable pad and the other end bonded. The pass / fail measurement (determination) of a defective memory chip that cannot be remedied even if a redundant circuit is used on a simple scale as a whole. This makes it possible to eliminate the need to execute a test program for defective storage circuit devices, thereby reducing the measurement time required for inspection of a plurality of storage circuit devices on a silicon wafer after repairing defective bits. You.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Several embodiments will be described below to describe the storage circuit device of the present invention in detail with reference to the drawings.

FIG. 1 shows a program circuit provided in a storage circuit device according to one embodiment of the present invention. This program circuit stores information on whether a defective bit can be remedied by a redundant circuit at the time of preliminary measurement of quality inspection on a silicon wafer. The program circuit includes a probe-dedicated (dedicated) pad 10 on which a probe 12 for electrically recognizing the state of the circuit itself, a fuse 11 made of polycrystalline silicon, and a resistor for the fuse 11 are provided. R1 and a local portion connected in series in this order, and the other end of a diode D1 having one end connected to a power supply (ground connection portion) provided in the device is connected to the resistor R1 side in the local portion. Note that this storage circuit device also includes a redundant circuit (not shown) for preliminary measurement, similarly to the conventional device.

Next, an inspection procedure for a storage circuit device having such a program circuit will be described. In the program circuit, when the defective bit cannot be remedied by the redundant circuit at the time of the preliminary measurement, the fuse 11 is cut in advance by a laser when performing the trimming described in FIG. That is, this program circuit
Whether the defective bit can be relieved by the redundant circuit can be stored depending on whether the fuse 11 is cut or not.

Next, when the Pass / Fail measurement is performed, the probe 12 is first set on the probe stand application type pad 10, and then a negative potential is applied to the probe 12 to determine whether the probe 12 is conductive or non-conductive. Thereby, in the case of non-conduction, it is possible to mark the memory chip as defective before executing the Pass / Fail determination.

As described above, according to the storage circuit device according to the embodiment, it is possible to judge a case where a defective circuit cannot be repaired by a redundant circuit only by first judging the presence or absence of a current in a program circuit in Pass / Fail measurement. Can be. Therefore, in Pass / Fail measurement, it is not necessary to execute a test program for a defective storage circuit device, so that the measurement time required for inspection is reduced. Specifically, the time required for the conventional preliminary measurement is 5 times.
If the time required for Pass / Fail measurement is about 15 seconds, and the time required for Pass / Fail measurement is about 15 seconds, the time required for Pass / Fail measurement can be reduced by about 2 to 3 seconds.

FIG. 2 shows a program circuit provided in a storage circuit device according to another embodiment of the present invention. FIG. 2A illustrates the configuration of the program circuit.
FIG. 2B further shows the modified program circuit.

In the above embodiment, the pad 10 of the probe stand application type is provided in the configuration of the program circuit so that the success or failure of the relief by the redundant circuit can be stored. In this embodiment, FIG. As shown, the pads 21, 22, and 23 of the bonding application type used when assembling the memory chip 20 into a case are used. These pads 2
The input protection circuits 25, 26,
27 are connected. Further, a fuse 24 is connected between the pad 22 and the input protection circuit 26. The pad 22, the fuse 24 and the input protection circuit 26
Are connected in series to form a basic configuration of a program circuit.

Since the address input terminal of the storage circuit device is generally connected to the gate of the MOSFET, the program circuit shown in FIG. 1 is modified by applying the program circuit shown in FIG. By doing
As shown in FIG. 2B, the address input terminal is a P-type M
A program circuit is formed by connecting a gate of T1 which is an OSFET and a gate of T2 which is an N-type MOSFET, and connecting a resistor R2 of about 1 to 2 kΩ and a pad 31 of a bonding application type to a fuse 32. Has little effect on operation. When the program circuit is configured using the address input terminals as described above, the number of probe terminals and the number of pads can be reduced.

In any case of the storage circuit device having the program circuit, the Pass / F is the same as in the first embodiment.
The time required for aile measurement can be shortened.

FIG. 3 shows a program circuit provided in a storage circuit device according to another embodiment of the present invention. This program circuit has a configuration in which two pads 41 and 42 of the probe stand application type are provided, and a fuse 43 and a resistor R3 are connected in series between these pads.
In the program circuit having such a configuration, the input protection circuit can be omitted, so that the number of components of the semiconductor memory device can be reduced.

Further, a program circuit can be formed by replacing either one of the pads 41 and 42 of the probe stand application type with a pad of the bonding application type in the storage circuit device according to another embodiment.

In the case of the storage circuit device provided with these program circuits, the time required for Pass / Fail measurement can be shortened as in the case of the above-described first embodiment and other embodiments.

[0026]

As described above, according to the storage circuit device of the present invention, at the time of preliminary measurement, information as to whether or not a defective bit can be remedied by a redundant circuit is stored in a simply configured program circuit. Since pass / fail measurement (judgment) of a defective memory chip that cannot be remedied even by using a redundant circuit can be omitted, a plurality of storage circuit devices on a silicon wafer after remedying a defective bit are targeted. It is possible to greatly reduce the measurement time in the quality inspection, and as a result, it is possible to ship a large number of non-defective storage circuit devices accurately.

[Brief description of the drawings]

FIG. 1 shows a program circuit provided in a storage circuit device according to one embodiment of the present invention.

FIGS. 2A and 2B show a program circuit provided in a storage circuit device according to another embodiment of the present invention, wherein FIG. 2A illustrates the configuration of the program circuit, and FIG. 2 shows a circuit.

FIG. 3 shows a program circuit provided in a storage circuit device according to another embodiment of the present invention.

FIG. 4 is a flowchart showing an inspection procedure by a redundant circuit in a conventional storage circuit device.

[Explanation of symbols]

10, 41, 42 Pad of probe-stand application type 21, 22, 23, 31 Pad of bond-application type 11, 24, 32, 43 Fuse 12, 44, 45 Probe 20 Memory chip R1, R2, R3 Resistance D1, D2 Diode T1 P-type MOSFET T2 N-type MOSFET

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G11C 29/00 H01L 27/10

Claims (4)

(57) [Claims] 1. A storage circuit device comprising a program circuit for storing information as to whether a defective bit can be remedied in a device obtained by a redundant circuit provided,
The program circuit includes a probe-stand type pad,
A local portion in which a fuse and a resistor are connected in series in this order, and the other end of a diode having one end connected to a power supply provided in the device is connected to the resistor side in the local portion. Storage circuit device. 2. A storage circuit device comprising a program circuit for storing information as to whether or not a defective bit can be remedied in a device obtained by an attached redundant circuit,
The memory circuit device, wherein the program circuit is configured by connecting a fuse between a bonding-applied pad and an input protection circuit. 3. A storage circuit device comprising a program circuit for storing information as to whether or not a defective bit can be remedied in a device obtained by an attached redundant circuit.
A memory circuit device, wherein the program circuit is configured by connecting both ends of a local portion formed by connecting a resistor and a fuse in series with pads of a probe stand application type. 4. A storage circuit device comprising a program circuit for storing information as to whether or not a defective bit can be remedied in a device obtained by an attached redundant circuit.
The memory is characterized in that the program circuit is configured such that one end of a local portion formed by connecting a resistor and a fuse in series is connected by a probe stand application type pad and the other end is connected by a bonding application type pad. Circuit device.