KR20050065170A - Method for manufacturing programmable variable condensor by using non volatile memory - Google Patents

Abstract

Disclosed is a method of manufacturing a programmable variable capacitor using a non-volatile memory (NVM) mainly used for frequency adjustment as a capacitor capable of varying capacity. The disclosed method is packaged into a test process of a variable capacitor using a programmable NVM, performing a pre-test, determining the amount of trimming capacity based on the test result, and then targeting the NVM cell using EEPROM, which is a nonvolatile memory. After deciding and programming, implement the desired capacity, test process to achieve the desired capacity, trimming the variable capacitor with good samples, and reprogramming is not possible due to programming errors. Trimming until it has a value. Therefore, there is an effect that can have a desired capacity value by selectively programming a nonvolatile memory by addressing it through a control signal from the outside.

Description

METHODS FOR MANUFACTURING PROGRAMMABLE VARIABLE CONDENSOR BY USING NON VOLATILE MEMORY}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the manufacture of semiconductor devices, and more particularly, to a method of manufacturing a programmable variable capacitor using a non-volatile memory (NVM) mainly used for frequency adjustment as a capacitor capable of varying capacitance. It is about.

In the prior art, there is a method of cutting a metal lead using a laser on a wafer when manufacturing a variable capacitor, or a method of connecting elements outside the chip. Trimming with a laser can damage a substrate, which requires a relatively large area in order to eliminate circuit damage that may occur.

Therefore, this method cannot be used after the package. In other words, if a trimming process is performed before the package, a defect is required to be discarded. As a result, there is no way to compensate for changes in capacity that may be caused by the package.

In addition, the method of connecting devices outside the chip may cause a loss of capacitance when the lead wire is connected, and it is impossible to implement a system on chip (SoC).

1 is a perspective view for explaining a capacitor which can change its capacity as a conventional variable capacitor 10 and can be mainly used for frequency adjustment.

1 shows a variable capacitance capacitor 10 called a trimmer, and ceramics are used as the dielectric. In addition, a polyester film or the like is also used as a dielectric.

It is made to be mounted on a printed board, and the screw portion 14 attached to the board to adjust the capacity is connected to either lead wire 12 so that a poor contact of the lead wire 12 or a system on chip There is a problem that it is impossible to use in an integrated application circuit.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and the main object of the present invention is to attach a capacitor using a nonvolatile memory to a capacitor array having a constant capacity in the configuration of a variable capacitor, and thus selectively connect the capacitors. The present invention provides a method of manufacturing a programmable variable capacitor using a nonvolatile memory.

In addition, another object of the present invention is to provide a method of manufacturing a programmable variable capacitor using a nonvolatile memory that can have a desired capacity value by selectively programming the nonvolatile memory by addressing it through a control signal from the outside.

Accordingly, the present invention provides a method of manufacturing a programmable variable capacitor using a nonvolatile memory capable of preventing damage to a substrate due to conventional laser trimming and correcting a capacitance error of a capacitor generated after a package is completed.

In addition, the present invention can not be corrected after the laser trimming operation only once, so if you make an error during trimming is a bad sample, using the NVM cell can be re-trimming can significantly lower the failure rate and lower the manufacturing cost The present invention provides a method of manufacturing a programmable variable capacitor using a nonvolatile memory.

The present invention for realizing the above object is packaged into a test procedure of a variable capacitor using a programmable NVM, and then performing a pre-test, after determining the degree of capacity to be trimmed based on the test results, the non-NVM cell Determining a target using EEPROM, a volatile memory, and then programming to implement the desired capacity, and after the test process reaches the desired capacity, trimming of the variable capacitor with good samples is completed, and programming errors do not have proper capacity values. If possible, the present invention provides a method of manufacturing a programmable variable capacitor using a nonvolatile memory, which includes trimming until a desired capacitance value is obtained.

According to another object of the present invention, there is provided a method of manufacturing a programmable variable capacitor using a nonvolatile memory, characterized in that the capacity of the variable capacitor is changed through a pin for giving a separate control signal even after the package.

According to still another object of the present invention, there is provided a method of manufacturing a programmable variable capacitor using a nonvolatile memory, characterized in that a desired capacitance value can be obtained by connecting a capacitor having a constant capacitance in parallel.

According to still another object of the present invention, in the application of a nonvolatile memory, the application of a single poly EEPROM using a CMOS process makes it possible to implement a nonvolatile memory, which requires no further processing in a logic CMOS process. Provided is a method of manufacturing a programmable variable capacitor.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings. In addition, this embodiment is not intended to limit the scope of the present invention, but is presented by way of example only.

2 is a view for explaining a method for circuitry to implement the desired capacitance basically in accordance with a preferred embodiment of the present invention.

As shown in Fig. 2, capacitor arrays C_0 to C-7 having constant capacitances on the left side are arranged in parallel, and each switch is connected to one node of the capacitor to connect the capacitors to implement desired capacitance.

In the drawing, both ends of the capacitor arrays C_0 to C_7 are all connected to one node, and the other side is connected to the switches NVM_0 to NVM_7 and connected to one node.

For a variable capacitor using this switch, the capacitance of the capacitor with the closed switch will be added. For example, as shown in the figure, when the switches NVM_0, NVM_1, and NVM_2 are closed, the total capacitor value becomes Ctotal = C_0 + C_1 + C_2.

3 is a circuit diagram of a switch implemented as an NVM cell in the variable capacitor using the switch shown in FIG. 2.

As shown in Fig. 3, a system-on-chip of a variable capacitor is enabled by using an EEPROM, which is a nonvolatile memory whose switch state is not cleared even when the power supply is cut off. As can be seen, according to a preferred embodiment of the present invention, the NVM cell transistor is implemented to enable programming of switching by facilitating data writing and erasing using control signals and control decoder circuitry.

According to an exemplary embodiment of the present invention, in order to switch the capacitor 'C_0' connected to A_0, a program is performed by addressing at a decoder receiving only NVM_0 inputs D_0 to D_2 from among the programmable NVM cell transistor arrays NVM_0 to NVM_7. And B_0 nodes may have the effect of being connected to each other. Therefore, according to a preferred embodiment of the present invention, it is possible to implement a system-on-chip to program the existing variable resistor in the above-described manner.

4A is a flowchart illustrating a process of testing and fabricating a variable capacitor using a conventional laser trimming method.

First, in step S10, after the fab out (fabout), it is subjected to a pre-test in step S12. Then, laser trimming is performed in step S14 to change the value of the variable capacitor. In the next step, after performing a post test whether the variable capacity is implemented at a desired value in S16, if it is bad, it is determined that it cannot be used as a bad sample in step S18, and if it is satisfactory, after performing the package in step S20, The final test is performed in S22. Subsequently, if it is determined in step S22 that it is defective, it is determined that it is impossible to use it as a capacitor by judging it as a bad sample in step S24. Is determined to be a good sample.

4B is a flowchart illustrating a process of testing and fabricating a variable capacitor using an NVM according to a preferred embodiment of the present invention.

As shown in Figure 4b, after the package in step S102 to test the variable capacitor using the programmable NVM in accordance with a preferred embodiment of the present invention, the pre-test is performed in step S104. In step S108, after determining the amount of capacity to trim based on the test result, the target NVM cell is determined using a method as shown in FIG. 3, and then programmed to implement a desired capacity.

Thereafter, in step S106, the trimming of the variable capacitor is completed with good samples when the desired capacity is reached through the test procedure. If programming does not have proper capacity because of error, reprogramming is possible, so trimming is possible until desired capacity is obtained.

5 is a cross-sectional view illustrating a structure of a typical single poly EEPROM in which a nonvolatile memory is implemented using a single poly EEPROM. Unlike the conventional method of implementing floating gates and control gates in a stacked type, the EEPROM is composed of a single poly without any additional process like a general CMOS process.

While the invention has been described in accordance with some preferred embodiments herein, those skilled in the art will recognize that many modifications and improvements can be made without departing from the true scope and spirit of the invention as set forth in the appended claims.

As described above, the present invention has the effect of having a desired capacity value by externally addressing a control signal and selectively programming a nonvolatile memory.

Therefore, the present invention has the advantage that it is possible to prevent damage to the substrate due to the conventional laser trimming and correction of the capacitance error of the capacitor generated after the package is completed, which can be applied to a circuit such as frequency adjustment.

In addition, the present invention can not be corrected after the laser trimming operation only once, so if you make an error during trimming is a bad sample, using the NVM cell can be re-trimming can significantly lower the failure rate and lower the manufacturing cost There are advantages to it.

1 is a perspective view for explaining a capacitor which can change the capacitance as a conventional variable capacitor, and can be mainly used for frequency adjustment.

2 is a view for explaining a method for circuitry to implement the desired capacitance basically in accordance with a preferred embodiment of the present invention.

3 is a circuit diagram of a switch implemented as an NVM cell in the variable capacitor using the switch shown in FIG. 2.

4A is a flowchart illustrating a process of testing and fabricating a conventional variable capacitor.

4B is a flowchart illustrating a process of testing and fabricating a variable capacitor according to a preferred embodiment of the present invention.

5 is a cross-sectional view illustrating a structure of a typical single poly EEPROM in which a nonvolatile memory is implemented using a single poly EEPROM.

Claims (4)

Packaged into a test procedure of a variable capacitor using a programmable NVM, and then performing a pretest; Determining the amount of capacity to trim based on the test result, and then determining a target by using the EEPROM, which is a nonvolatile memory, and programming the NVM cell to implement a desired capacity; Completing the trimming of the variable capacitor with a good sample when the desired capacity is reached through the test process; And If you do not have a proper capacity value due to programming error, you can reprogram it. Method of manufacturing a programmable variable capacitor using a nonvolatile memory, characterized in that it comprises a. The method of claim 1, The method of manufacturing a programmable variable capacitor using a nonvolatile memory, characterized in that for changing the capacity of the variable capacitor through a pin that can give a separate control signal even after the package. The method of claim 1, The desired capacitance value is a method of manufacturing a programmable variable capacitor using a nonvolatile memory, characterized in that obtained by connecting a capacitor having a constant capacitance in parallel. The method of claim 1, The method of manufacturing a programmable variable capacitor using a nonvolatile memory, characterized in that by applying a single poly EEPROM using a CMOS process without the need for further processing in a general logic CMOS process in applying the nonvolatile memory.