KR100526454B1 - Repaire circuit provided with programming device of antifuse - Google Patents

Abstract

The present invention relates to a repair circuit having an anti-fuse programming device. In particular, the programming device includes a first program voltage generator for generating a high level first voltage and a second program voltage generator for generating a negative second voltage. And a ground voltage supply unit driven to a signal inverting the output of the anti-fuse address generator, the voltage drop unit, the booster unit, and the anti-fuse address generator, and a power supply voltage supply unit driven to the output signal of the anti-fuse address generator. And a first switch signal generator for outputting a signal inverted by the signal of the connection node of the voltage dropping part and the ground voltage supply part, and a signal for outputting the signal inverted by the signal of the connection node of the booster part and the power supply voltage supply part. A first program voltage supply unit for applying a first voltage to the antifuse by the output of the second switch signal generator and the first switch signal generator; 2 includes a second program voltage supply for applying a second voltage to the anti-fuse by the output of the switch occurs. Therefore, the present invention can be easily and reliably programmed using the voltage difference across the anti-fuse, so that the repair process is possible even after the package.

Description

REPAIRE CIRCUIT PROVIDED WITH PROGRAMMING DEVICE OF ANTIFUSE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a repair circuit of a semiconductor memory device, and more particularly, to a programming device having an antifuse consisting of conductive films spaced apart from each other and insulating films therebetween programmed for replacing defective memory cells with redundancy cells. The present invention relates to a repair circuit for performing programming by insulating and insulating the insulating film according to a voltage difference generated from an overvoltage generator.

In general, a semiconductor memory device installs spare cells of a memory for each sub-array block. For example, spare rows and columns are pre-installed for each 256K cell array. Replace with a spare memory cell. When the repair process is completed, the repair circuit performs a programming on the internal circuit that selects a defective memory cell through a test and replaces it with an address signal of a corresponding spare cell. Accordingly, when an address corresponding to a defective line is input in actual use, The selection changes to a line of extra cells. This programming method includes an electric fuse that melts and cuts a fuse with an overcurrent, and a fuse that burns with a laser beam. Among these methods, a method of cutting a fuse using a laser is simple, reliable, and easy to lay out. It is used. As the fuse material, polysilicon wiring or metal wiring is used.

However, the laser type programming method requires a repair process using expensive laser equipment to replace a separate defective cell with a redundancy cell, and a part to which a fuse is cut by performing a fuse window process during the manufacturing process. The repair process is complicated and cumbersome because the laser is irradiated onto the laser to be programmed and the passivation process is performed.

To solve this problem, semiconductor memory devices, such as programmable logic arrays, programmable logic devices, programmable ROMs and DRAMs, have an anti-fuse that can be easily programmed even at the package level. Similar to the capacitor structure of, the upper and lower conductive films and the insulating films therebetween are composed of ONO (Oxide / Nitiride / Oxide) films.

At this time, the programming of the anti-fuse causes the insulating film to be insulated-breakdown by the programming voltage (about 8 to 11 V), which is a voltage difference applied to the conductive films, and to make the two conductive films short-circuit (on state). Change to the word line or bit line of the selected repair circuit.

It is an object of the present invention to provide a programming device capable of supplying a stable programming voltage to an antifuse in a repair circuit having an antifuse as described above, thereby providing a bad memory by an electric programming method using a high voltage without using expensive laser equipment. The repair process for replacing a cell with a redundancy cell is reliably provided to provide a repair circuit having a simple anti-fuse programming device.

In order to achieve the above object, the present invention provides an anti-fuse programming device composed of conductive films spaced apart from each other and an insulating film interposed therebetween, programmed to replace a defective memory cell with a redundancy cell. A first program voltage generator that generates, a second program voltage generator that generates a set negative second voltage, an antifuse address generator that generates an antifuse address signal, and a first voltage of the first program voltage generator Is connected between the voltage drop section for dropping the voltage to a predetermined level, the voltage booster for boosting the second voltage of the second program voltage generator to a predetermined level, and the output of the anti-fuse address generator is inverted. A ground voltage supply driven between the booster and the power supply terminal, A first switch signal generator between the power supply voltage supply unit driven to the output signal and the output of the first program voltage generator and a ground terminal and outputting a signal inverted by a signal of a connection node of the voltage drop unit and the ground voltage supply unit; A second switch signal generator between the output of the second program voltage generator and the ground terminal and outputting a signal inverted by a signal of a connection node of the booster unit and the power supply voltage supply unit; A first program voltage supply unit which is driven to apply a first voltage to one conductive film of the antifuse, and a second program voltage supply which is driven by an output of the second switch generation unit to apply a second voltage to the other conductive film of the antifuse It is characterized by comprising a part.

In addition, the present invention allows the first voltage of the first program voltage generator to be about 5V and the second voltage of the second program voltage generator to be about -3V.

According to the present invention, the repair circuit having an antifuse can be programmed to the antifuse simply and reliably using a high voltage programming method, thereby enabling a repair process even after the package.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a circuit diagram illustrating an anti-fuse programming device according to an exemplary embodiment of the present invention.

Referring to this, the anti-fuse programming apparatus of the present invention includes a first program voltage generator 10 generating 5V, which is a set first voltage, and a second program voltage generator, generating -3V, which is a set second voltage. 20 and an anti-fuse address generator 30 for generating an anti-fuse address signal af_add.

The programming device of the present invention is connected between the voltage drop unit 42 for dropping the signal applied from the first program voltage generator 10 to a predetermined voltage, and is connected between the voltage drop unit 42 and the ground terminal. A ground voltage supply unit 44 driven to a signal inverting the output of the address generator 30 through the inverter I1, and a booster for boosting a signal applied from the second program voltage generator 20 to a predetermined voltage; And a power supply voltage supply unit 48 connected between the booster unit 46 and the power supply terminal and driven to an output signal of the anti-fuse address generator 30. At this time, the voltage drop section 42 and the power supply voltage supply section 48 are PMOS transistors, the ground voltage supply section 44 and the boosting section 46 is composed of NMOS transistors.

Further, the programming device of the present invention is located between the output of the first program voltage generator 10 and the ground terminal and is inverted by the signal of the voltage drop unit 42 and the connection node n2 of the ground voltage supply unit 44. A connection node n4 between the booster 46 and the power supply voltage supply unit 48 between the first switch signal generator 52 for outputting a signal and the output of the second program voltage generator 20 and the ground terminal; And a second switch signal generator 54 for outputting a signal inverted by the signal. In this case, both the first and second switch signal generators 52 and 54 use a conventional CMOS transistor, and the CMOS transistors of the first switch signal generator 52 are connected to the first program voltage generator 10. The second switch signal generator 54 has a PMOS and NMOS transistor having a common gate connected to the ground voltage terminals, and the second switch signal generator 54 has a gate connected to the ground between the second program voltage generator 20 and the ground voltage terminal. Consists of

In addition, the programming device of the present invention is driven by the output of the first switch signal generator 52 to apply the first program voltage generator 10 to the one conductive film of the anti-fuse 60. The second program voltage supply unit driven by the voltage supply unit 56 and the output of the second switch generator 54 to apply the output of the second program voltage generator 20 to the antifuse 60 to another conductive film. (58). At this time, the first and second program voltage supply units 56 and 58 are composed of PMOS and NMOS transistors, respectively.

In addition, the programming device of the present invention includes a first diode D1 connected in a reverse direction to the node n6 between the first program voltage supply unit 10 and the antifuse 60, and the second program voltage supply unit 20 and the anti It comprises a second diode (D2) connected in the forward direction to the node (n7) between the fuse (60). In this case, the first diode D1 connects the node n6 to the power supply voltage Vcc terminal, and the second diode D2 connects the node n7 to the ground voltage terminal.

The programming circuit of the antifuse according to the present invention operates as follows. First, when the antifuse address signal af_add is generated through the antifuse address generator 30, the signal becomes 3 V of the Vcc level and the inverter I1. 0V is applied to node n1 through

Then, the ground voltage supply unit 44 is turned off, and the 5V voltage applied from the first program voltage generator 10 is assumed to be Vtp (-1V) at 5V by the threshold voltage of the PMOS transistor of the voltage drop unit 42. Node n2 takes about 4V.

The NMOS transistor of the first switch signal generator 52 is turned on by 4V of the node n2, so that 0V is applied to the n3 node, and the PMOS of the first program voltage supply 56 is applied by the voltage level of this node. The transistor is turned on to apply 5V of the first programming voltage generator 10 to the node n6. Then, a high voltage of about 5V is applied to any one of the conductive films of the antifuse 60.

On the contrary, when the anti-fuse address signal af_add is generated through the anti-fuse address generator 30, the signal becomes 3 V at the Vcc level, and the PMOS of the power supply voltage supply unit 48 is turned off. At this time, the node n4 becomes -2V, which is increased from -3V to the threshold voltage of the transistor (assuming 1V) by the NMOS transistor of the booster 46.

The PMOS transistor of the second switch signal generator 54 is turned on by the voltage applied to the node n4, and 0V is applied to the node n5. At this time, the NMOS transistor of the second program voltage supply unit 56 is turned on by the voltage level of the node n5, and -3V of the second programming voltage generator 20 is applied to the node n7.

Then, a negative voltage of about -3V is applied to the other conductive film of the antifuse 60.

As a result, 5V and -3V are applied to both ends of the conductive film of the antifuse 60 to have a voltage difference of about 8V. As a result, the insulating film between the conductive films is insulated and destroyed, and a fuse is shorted.

Due to the short-circuit state of the anti-fuse 60, the voltage of the node n6 and the node n7 is about to be the same, but the node voltage (-3V) is short-circuited and tries to equalize the voltage level applied to the nodes n6 and n7. At this time, as the first and second diodes D1 and D2 are both turned on to generate a current path through the diodes D1 and D2 from the power supply voltage Vcc to the ground terminal, the voltages of the nodes n6 and n7 are approximately. Make it Vcc / 2.

On the contrary, if the antifuse address af_add is not generated through the anti-fuse address generator 30, the NMOS of the ground voltage supply unit 44 is turned on and the PMOS of the power supply voltage supply unit 48 is turned on to eventually turn on the first. And all transistors of the second program voltage supply unit 56 are turned off. As a result, programming voltages of 5 V and −3 V are not applied to both ends of the anti-fuse 60, so that the above-described programming operation of the anti-fuse 60 is not performed.

FIG. 2 is a circuit block diagram illustrating a repair circuit operation having the anti-fuse programming device shown in FIG. 1, which is an anti-fuse programming unit 100, an anti-fuse programming detection unit 102, and a repair path 104. ) And the normal path 106.

Referring to this, in the present invention, when the anti-fuse programming is completed through the anti-fuse programming unit 100, the power of all of the anti-fuse programming circuits of FIG. 1 is turned off.

The anti-fuse programming detector 102 then determines whether the anti-fuse is cut or not. If the fuse is blown, the repair path 104 is enabled and the normal path 106 is disabled to select a repair wordline (W / L) or bitline (B / L) signal. Accordingly, the repair circuit having the anti-fuse programming device of the present invention replaces the redundancy cell with a defective memory cell according to the selected repair word line or bit line signal.

In contrast, if the fuse is not blown, the repair path 104 is disabled and the normal path 106 is enabled to select a normal word line (W / L) or bit line (B / L) signal.

As described above, according to the present invention, programming of the antifuse can be performed simply and reliably using the voltage difference across the antifuse, so that the repair process can be performed even after the package.

As a result, the present invention can improve the problem of the conventional programming method of cutting polysilicon or metal fuse using expensive laser equipment, thereby reducing the repair process cost.

1 is a circuit diagram showing an anti-fuse programming device according to an embodiment of the present invention;

FIG. 2 is a circuit block diagram for explaining a repair circuit operation with the antifuse programming device shown in FIG.

Explanation of symbols on main parts of drawing

10: first program voltage generator 20: second program voltage generator

30: anti-fuse address generator 42: voltage drop

44: ground voltage supply 46: boost

48: power supply voltage supply unit 52: first switch signal generation unit

54: second switch signal generator 56: first program voltage supply

58: second program voltage supply unit

60: Antifuse

Claims (4)

In the anti-fuse programming device consisting of conductive films spaced apart from each other and an insulating film interposed therebetween, programmed to replace a defective memory cell with a redundancy cell, A first program voltage generator configured to generate a set high level first voltage; A second program voltage generator configured to generate a set negative second voltage; An antifuse address generator for generating an antifuse address signal; A voltage drop unit configured to drop the first voltage of the first program voltage generator to a predetermined level; A booster boosting the second voltage of the second program voltage generator to a predetermined level; A ground voltage supply unit connected between the voltage drop unit and a ground terminal and driven to a signal inverting an output of the antifuse address generator; A power voltage supply unit connected between the boosting unit and a power supply terminal and driven to an output signal of the anti-fuse address generator; A first switch signal generator between the output of the first program voltage generator and a ground terminal and outputting a signal inverted by a signal of a connection node of the voltage drop unit and the ground voltage supply unit; A second switch signal generator between the output of the second program voltage generator and a ground terminal and outputting a signal inverted by a signal of a connection node of the booster and the power supply voltage supply unit; A first program voltage supply unit which is driven by an output of the first switch signal generator to apply the first voltage to an anti-fuse conductive film; And And a second program voltage supply unit which is driven by an output of the second switch generating unit and applies the second voltage to another conductive film of the antifuse. 2. The repair circuit of claim 1, wherein a first diode is connected to a node between the first program voltage supply unit and the antifuse in a reverse direction to apply a power supply voltage to the node. 2. The repair circuit of claim 1, wherein a second diode is connected to a node between the second program voltage supply unit and the antifuse in a forward direction to lower a voltage applied to the node to ground. 2. The repair circuit according to claim 1, wherein the first voltage of the first program voltage generator is about 5V and the second voltage of the second program voltage generator is about -3V.