KR20030076084A - Apparatus for writing and reading data by using cantilever - Google Patents

Abstract

PURPOSE: A device for writing and reading data using a cantilever is provided to have a unit for writing, reading, and storing data, and to selectively control writing and reading processes of the cantilever, thereby reducing power consumption and power line noise as improving operational speed. CONSTITUTION: A cantilever array(100) reads and writes data. A temporary storage device(200) stores the read and written data. An input/output device(300) outputs the written data or inputs the read data from the temporary storage device. A control device(400) selectively controls the cantilever array and the temporary storage device, respectively. Each cantilever has a local register for being applied with the written data from the temporary storage device and storing the applied data therein. The cantilever array comprises as follows. The cantilevers output a sensing voltage between dummy resistors by varying a resistance value of a piezo-resistor with the data. Comparators compare the output sensing voltage with a reference voltage, and output data signals.

Description

Apparatus for writing and reading data by using cantilever}

The present invention relates to a data recording and reading device using a cantilever, and more particularly, to a device for storing write and read data, thereby selectively performing recording and reading in the cantilever and adjusting the input / output of the input / output device to reduce power consumption. The present invention relates to a data recording and reading device using a cantilever that can reduce power line noise and improve operating speed.

In general, atomic force microscopy (AFM) uses small rods called cantilever made by micromachining. The cantilever is designed to bend up and down easily, even by microscopic forces, and at the tip is a pointed needle about the size of a few atoms. When the probe approaches the surface of the sample, a force (pulling force) or a pushing force (repulsive force) is applied between the atoms at the tip of the probe and the atoms at the surface of the sample, and it is a device for sensing the force.

The principle of this atomic force microscope is now being applied to nano-exposure devices and data storage devices.

In the operating mode of the atomic force microscope, in the contact mode, repulsive force is used. The magnitude of the force is very small (about 1-10 nm), but the cantilever is also very sensitive, and thus is bent by the force.

In order to measure the bending of the cantilever up and down, a laser beam is irradiated to the cantilever, and the angle of the light reflected from the upper surface of the cantilever is measured using a photodiode.

However, since a detection device using a laser and a photodiode requires a complicated and sophisticated device, a method of using a device that integrates and detects a resistive sensor on a cantilever has been proposed (US005266801A).

The cantilever technology incorporating such piezo-resistive sensors is easier to manufacture and simpler than photodiodes, thus opening up the possibility of data storage using cantilevers.

A representative nuclear microscope data storage device is Milliped, announced by IBM. In this millifeed, the 'write' operation is performed by using a resistive heater embedded in the tip of the atomic force microscope to indent the media consisting of PMMA with heat generated by the heater.

The written data is scanned with the tip of the cantilever, and the piezo resistor detects the degree of cantilever deflection and performs a 'read' operation.

In the case of the millifeed, there is no suggestion on which device and method will be used in a special read or write operation, except for placing the cantilever in parallel to improve the write and read operations.

Scanning Probe Microscopy (SPM) A cantilever array that senses data in a data storage device and performs a read operation, and vice versa, a scanning probe microscope data storage head (hereinafter referred to as a 'cantilever head'). ).

In order to perform a reading / writing operation with such a cantilever head, a conventional method is possible to perform a read / write operation in a manner similar to that of a DRAM. There is a method of selecting a cantilever to read (or write) data at the same time, outputting the data through an output buffer, and then moving the cantilever head to the next data position.

Let's take an example of a cantilever head with an array of 32x32 cantilevers in scanning probe microscope data storage.

In the prior art, when operating similarly to DRAM, when k (1 ≦ k ≦ 1024) cantilevers are selected and performed a read operation in a 32 × 32 cantilever array, data is output only to k output buffers.

However, if all 32x32 (1024) cantilevers are selected to perform a read operation, 1024 data output buffers and output pads should be placed.

In addition, since the data is recorded, the 1024 input / output buffers are required when designing 32x32 cantilever heads.

Therefore, a conventional data recording and reading device using a cantilever requires an input / output buffer equal to the number of cantilever arrays, thereby reducing circuit design margins and increasing power consumption and power line noise. It was.

In addition, the data can be read simultaneously with the arrayed cantilevers, moved to the next position, and the reading or writing operation cannot be performed during the time of sensing again, and thus the operation speed is significantly reduced.

Accordingly, the present invention provides a data recording and reading apparatus using a cantilever that can be read and written sequentially after storing the sensed data and the data for recording, which are devised to solve the above problems. Its purpose is to.

Another object of the present invention is to provide a data recording and reading device using a cantilever that can freely design an input / output device by selectively controlling the cantilever array and the storage device, respectively, thereby reducing power consumption and power line noise.

Another object of the present invention is to improve the operation speed by sensing and storing data, and then outputting a sensing data signal when sensing and moving to the next data, or storing data for the next recording when performing recording. It is an object of the present invention to provide a data recording and reading device using a cantilever.

A preferred aspect for achieving the above objects of the present invention comprises: a cantilever array for reading and writing data;

A temporary storage device for storing the data;

There is provided a data recording and reading device using a cantilever composed of an input / output device for outputting recording data of the temporary storage device or receiving read data.

1 is a block diagram of a data recording and reading apparatus using a cantilever according to the present invention.

2 is a circuit diagram of a data recording and reading apparatus using a cantilever according to the present invention.

3 is a perspective view of a cantilever according to the present invention.

4 is a circuit diagram of a cantilever according to the present invention.

5 is a circuit diagram illustrating a comparator comparing and outputting a reference voltage and a sensing voltage according to the present invention.

6 is a circuit diagram illustrating a reference voltage generator and an output buffer.

7A and 7B are timing diagrams of a control signal applied to a data recording and reading apparatus using a cantilever according to the present invention.

<Description of Symbols for Main Parts of Drawings>

20: silicone support 27: tip

29: cantilever unit 100: cantilever array

101: cantilever 131,210,230: switching means

130: local register 150: reference voltage generator

160: output buffer 161,171: comparator

181,182: inverter 200: temporary storage device

220: Register 300: I / O device

301: data output buffer 400: control device

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

1 is a block diagram of a data recording and reading apparatus using a cantilever according to the present invention, comprising: a cantilever array 100 for reading and writing data; A temporary storage device 200 for storing the data; An input / output device (300) for outputting write data of the temporary storage device (200) or receiving read data; Control device 400 for selectively controlling the cantilever array 100 and the temporary storage device 200, respectively.

2 is a circuit diagram of a data recording and reading apparatus using a cantilever according to the present invention. First, the cantilever array 100 is n X m (where n is 1,2,3, ..., n, and m is 1,2,3, ..., m) cantilevers are arrayed.

As shown in FIG. 3, the cantilever 101 is floated from the bottom, and the tip 27 is provided at the tip, and the piezoelectric sensor resistor whose resistance value is changed by the bending force detected by the tip 27. A cantilever portion 29 in which R1 is formed; The cantilever part 29 is supported, and is composed of a silicon support 20 having a dummy resistor R2 electrically connected to the piezo sensor resistor R1.

Power is supplied through the electrode 26 connected to the piezoelectric sensor resistor R1, and the piezoelectric sensor resistor R1 is electrically connected to the connection portion 25 of the dummy resistor R2 through the electrode line 23. The resistor R2 is connected to the electrode 24 to ground.

Here, the cantilever 101, as shown in Figure 4, one terminal of the piezo sensor resistor (R1) is connected to the power supply (Vcc), the other terminal is connected to one terminal of the dummy resistor (R2), The other terminal of the dummy resistor is connected to the grounding switching means 29, and the sensing voltage V2 at which the data is sensed at a point 'a' between the piezo sensor resistor R1 and the dummy resistor R2. Is output.

In addition, the sensing voltage V2 output at the point 'a' between the piezoelectric sensor resistor R1 and the dummy resistor R2 of each cantilever 101 is a reference voltage output from the reference voltage generator 150. In comparison with, the data signal outputs whether the data signal is " 1 " or " 0 " at a predetermined voltage or zero voltage (see FIGS. 2, 5 and 6).

In addition, the output voltage of the comparator 171 is inverted twice in two inverters 181 and 182 to output a predetermined or zero distortion voltage (see FIGS. 2 and 5).

As described above, the reference voltage generator 150 has a power supply Vcc and third and fourth resistors R ₃ and R ₄ connected in series, and the fourth resistor R ₄ as shown in FIG. 6. Is connected to the switching means 151 connected in series, so that the control signal PHI r of the control device is applied only when the tip of the cantilever scans the media so that the third and fourth resistors R ₃ and R ₄ Generates reference voltage at connection point 'b'.

Here, the reference voltage generator 150 may be freely arranged in the cantilever array 100 by one or several per row or per column.

In addition, an output buffer unit 160 is connected to an output terminal of the reference voltage generator 150 to prevent attenuation and fluctuation of the output reference voltage. In this case, the output voltage of the reference voltage generator 150 is output. Is input from the negative terminal of the comparator 161, the feedback voltage is input from the positive terminal of the comparator 161, the comparator 161 outputs a reference voltage (V1).

Then, when the data recording and reading apparatus using the cantilever of the present invention has n x m cantilevers arranged in the cantilever array, first, the data reading operation will be described.

At this time, in order to select the first to third columns of cantilevers to read data, the control signals PHI r, PHIa, PHI b, and PHI w of the control device control the operation of the first to third columns of cantilevers. The other cantilevers are not operated because no control signal is applied.

More specifically, the PHI r control signal is enabled in the first cantilever 101 of the selected one-column cantilever so that the first cantilever 101 senses data, and the piezo resistor sensor R1 and the dummy resistor R2 In between, the sensing voltage is drawn and applied to the comparator 171.

The comparator 171 receives the PHI r control signal, compares the reference voltage output from the reference voltage generator 150 with the sensing voltage, and outputs whether the data signal is “1” or “0” as a predetermined voltage or zero voltage. .

The output of the comparator 171 is stored in the first register 220 of the temporary storage device 200 while the switching means 210 of the temporary storage device 200 receiving the PHIa control signal is turned on.

In this way, the cantilevers in the first to third columns receive control signals of PHI r and PHIa of the control device, and store the data sensed output values in registers of the temporary storage device 200.

When the storage is finished, the control device stops the application of the control signals of PHI r and PHIa to block unnecessary current consumption in the cantilever array.

Thereafter, the cantilever array moves to a position where the next data is located, and during the sensing time, the control device applies a PHI b control signal to the switching means 230 of the temporary storage device 200 and switches it to switch the input / output device 300. Output to the data output buffer 301, the data output buffer 301 transmits the data signal sensed in the first cantilever of the first column of the cantilever array through the pin 303 to an external device.

Here, the switching means 230 is preferably configured in a plurality, so as to correspond to each of the arrayed cantilever, and the PHI b control signal is also a plurality of control signals (PHI 1b, PHI 2b, PHI 3b, ..., PHI mb) are applied to sequentially enable the plurality of switching means to output the sensed data signal stored in the registers of the temporary storage device 200 to the input / output device 300. It is desirable to.

Of course, the control device may apply the stored data signal as another control signal to be sequentially transmitted to the input / output device.

Therefore, in the present invention, it is not necessary to design an input / output device in the same number as the conventional cantilever, and the designer can freely design the input / output device, thereby reducing power consumption and power line noise.

In addition, by sensing and storing data, and then sensing and moving to the next data, by outputting a sensing data signal, the data recording and reading device using the cantilever of the present invention can improve the operation speed compared to the conventional apparatus. There is this.

Second, the data recording operation in the data recording and reading apparatus using the cantilever of the present invention will be described.

While the cantilever array 100 moves to a location to store data, the switching means 230 of the temporary storage device 200 is enabled with a control signal, so that each of the arrayed cantilevers temporarily stores a data signal for recording data. The plurality of registers of the storage device 200 are sequentially stored.

When the data signal is stored in the plurality of registers, the PHIa control signal is applied to the switching means 210 to enable the switching means 210 connected to the selected cantilever of the cantilever array 100.

Then, the data signal is stored in the local register 130 of the selected cantilever, the switching means 131 is switched to the switching means 131 by the PHIw control signal, and the data stored in the local register 130 is recorded by the selected cantilever.

Here, the data stored in the temporary storage device 200 may be directly transmitted to the corresponding cantilever to perform a recording operation.

As shown in FIG. 3, boron is lowered around the tip 27 formed in the cantilever 36 to use the tip as a heater, and the cantilever portion 29 has a high doped region 35. By transmitting the electrical signal to the tip by forming a to be able to perform a recording operation.

7A and 7B are timing diagrams of a control signal applied to a data recording and reading apparatus using a cantilever according to the present invention. First, when performing data reading in FIG. 7A, cantilevers selected from the cantilever array perform scanning and sensing. The PHI r control signal is applied to the reference voltage generator, and then PHIa is applied to the switching means 210 shown in FIG. 2 in order to store the sensed data in the registers of the temporary storage device.

Then, in order to sequentially transmit the sensed data stored in the registers of the temporary storage device to the input / output device, a plurality of control signals (PHI 1b, PHI 2b, PHI 3b, ..) , PHI mb) is applied.

At this time, the PHI r control signal is applied to the reference voltage generator, and then the cantilevers selected in the cantilever array perform scanning and sensing operations.

As a result, the input / output device of the present invention outputs the sensed data sequentially input, thereby eliminating the need to design the input / output device in the same number as the conventional cantilever.

In addition, when performing data recording in FIG. 7B, when data for recording is input from the input / output device, a plurality of control signals PHI 1b, PHI 2b, PHI 3b, which are selectively provided to the switching means 230 of the temporary storage device. ..., PHI mb) is sequentially applied to store data for writing in the registers of the temporary storage device.

Then, the PHI a control signal is applied to the switching means 210 of the temporary storage device to store data for writing stored in the registers in a local register connected to each of the arrayed cantilevers, and subsequently, the switching means 131 Switching to the PHI w control signal causes the cantilever to perform writing by data.

Here, when the cantilever performs recording by the PHI w control signal, the plurality of control signals PHI 1b, PHI 2b, PHI 3b,..., PHI mb are sequentially applied to the switching means 230. The data for writing is stored in the registers of the temporary storage device.

As described in detail above, the present invention does not need to design an input / output device equal to the number of conventional cantilevers, and the designer can freely design the input / output device, thereby reducing power consumption and power line noise.

In addition, when sensing and storing data, and then moving to and sensing the next data, by outputting a sensing data signal, an operation speed can be improved.

Although the invention has been described in detail only with respect to specific examples, it will be apparent to those skilled in the art that various modifications and variations are possible within the spirit of the invention, and such modifications and variations belong to the appended claims.

Claims (6)

A cantilever array for reading and writing data; A temporary storage device for storing the data; And an output device for outputting the recording data of the temporary storage device or receiving the read data. The method of claim 1, And a control device for selectively controlling the cantilever array and the temporary storage device, respectively. The method of claim 1, To record data, And each of the arrayed cantilevers further comprises a local register for receiving and storing data for writing from the temporary storage device. The method of claim 1, The cantilever array has a read data for A plurality of cantilevers for varying a resistance value of the piezo sensor resistor R1 based on the sensed data and outputting a sensing voltage V2 between the dummy resistors R2; And a comparator for outputting a data signal by comparing the sensing voltage V2 output from each of the plurality of cantilevers with a reference voltage V1 output from a reference voltage generator. Reader. The method according to claim 1 or 2, And a switching means for switching data for recording by a control signal (PHIw) of a control device between the cantilever and the local register. The method according to claim 1 or 2, The temporary storage device, Switching means for switching read and write data to each of the arrayed cantilevers by a control signal PHI a of a control device; And a switching means for switching the read and write data to the input / output device by a control signal (PHI b) of a control device.