JP2008103565A - Adjustment pattern structure for ladder resistance and electronic component having the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adjustment pattern structure for a ladder resistance that allows high-accuracy resistance-value adjustment by a trimming operation in one step without requiring two steps of coarse adjustment and fine adjustment, and an electronic component having the same. <P>SOLUTION: The adjustment pattern structure for a ladder resistance has first/second column parts formed on a substrate and a plurality of ladder parts formed between the first/second column parts in parallel. It comprises a first input/output part provided at one end of the first column part and a second input/output part provided at the opposite end of the second column part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a ladder resistor adjustment pattern structure and an electronic component having the same, and more particularly to a ladder resistor adjustment pattern structure capable of finely setting an adjustment amount and an electronic component having the same.

  In an electronic component having a ladder resistance, there is a method of adjusting a resistance value by trimming a part of an adjustment pattern structure in a ladder resistance region formed on a semiconductor substrate.

  As a conventional thin film resistor adjustment pattern structure, there is a thin film resistor having a ladder structure (Patent Document 1). In this thin film resistor, a ladder resistor adjustment pattern structure for adjusting a resistance value is provided between an input portion and an output portion of the resistor. The thin film resistor can be adjusted to the optimum resistance value by sequentially cutting the ladder portion with a laser beam while measuring the resistance value.

As another thin film resistor adjustment pattern structure, there is a thin film resistor composed of a coarse adjustment trimming portion and a fine adjustment trimming portion (Patent Document 2). Fine adjustment of the resistance value is performed by cutting the fine line portion of the meandering ladder pattern in order to make coarse adjustment, and finely adjusting the depth of cut by cutting the resistance of the fine adjustment trimming portion in two places from the same direction. Is.
Japanese Utility Model Publication No. 72-106 JP-A-159899

  However, according to the adjustment pattern structure of the thin film resistor in Patent Document 1, it is said that the ladder portion can be adjusted to the optimum resistance value by sequentially cutting with a laser beam. Since it is difficult to perform, there is a problem when a highly accurate resistance value is required.

  Further, according to the adjustment pattern structure of the thin film resistor disclosed in Patent Document 2, since the fine adjustment trimming unit is provided, it is possible to cope with a case where a highly accurate resistance value is required. However, when the resistance value is adjusted, coarse adjustment is performed. And two steps of fine adjustment are required, and there is a problem that it takes time to adjust the resistance value.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a ladder resistor adjustment pattern structure capable of highly accurate resistance value adjustment by a trimming operation in one step without requiring two steps of rough adjustment and fine adjustment, and an electronic component having the same. It is to provide.

  [1] According to one aspect of the present invention, the first and second pillar portions formed on the substrate, and the plurality of ladder portions formed in parallel between the first and second pillar portions, The first input / output unit provided at the end of the first column part and the second input provided at the end of the second column part opposite to the end part. And a ladder resistor adjustment pattern structure characterized by comprising an output section.

  [2] The ladder resistance adjustment pattern according to [1], wherein a pattern width of the first and second column portions is larger than a pattern width of the ladder resistor. It may be a structure.

  [3] According to one aspect of the present invention, the first and second pillar portions formed on the substrate, and a plurality of ladder portions formed in parallel between the first and second pillar portions, The first input / output unit provided at the end of the first column part and the second input provided at the end of the second column part opposite to the end part. An electronic component comprising: a ladder resistor having an output portion as a circuit element, wherein at least one of the ladder portions of the ladder resistor is subjected to a trimming process for adjusting a resistance value. .

  [4] The above-mentioned [3], wherein the adjustment pattern of the ladder resistor is formed so that the pattern width of the first and second column portions is larger than the pattern width of the ladder resistor. It may be an electronic component described in 1.

  According to the embodiment of the present invention, there is provided an adjustment pattern structure of a ladder resistor capable of highly accurate resistance value adjustment by trimming work in one step without requiring two steps of coarse adjustment and fine adjustment. It becomes possible to provide the electronic component which has.

(Embodiment of the present invention)
FIG. 1A is a circuit configuration diagram showing a ladder resistor adjustment pattern structure according to an embodiment of the present invention, and FIG. 1B shows a ladder resistor pattern layout of FIG. 1A formed on a substrate. FIG.

  The ladder resistor adjustment pattern structure according to the embodiment of the present invention includes a first and second pillar portions formed on a substrate and a plurality of parallel portions formed between the first and second pillar portions. And a ladder part.

  The substrate is a semiconductor substrate such as Si, but is not particularly limited to the semiconductor substrate, and any substrate can be used as long as a resistance element or the like can be formed thereon. When the ladder resistor adjustment pattern structure according to the embodiment of the present invention and the electronic component having the same are formed on a semiconductor substrate, the electronic component having a resistance element or the like can be formed by a known semiconductor process. Description of the manufacturing process is omitted.

  As shown in FIG. 1A, a resistor Ra is connected as a first column portion, and a resistor Ra is connected as a second column portion to form a pair of column portions on the substrate. . A resistor Rb is connected in parallel between the resistors Ra of the first column portion and between the resistors Ra of the second column portion to constitute a ladder-shaped resistor. With such a configuration, a ladder resistor adjustment pattern structure is formed. This circuit configuration is represented by a pattern layout formed on the substrate as shown in FIG.

  That is, as shown in FIG. 1B, the ladder resistor 10 has a first column portion 11 and a second column portion 12 connected to the contact regions 14 and 15 which are input / output portions, respectively. A pair of pillar portions are formed, and ladder portions 13a to 13g are formed in parallel between the two pillar portions.

  Here, the contact region 14 is connected to the end portion of the first column portion 11, and the contact region 15 is connected to the end portion of the second column portion 12 far from the end portion of the first column portion 11, These end portions, that is, the contact regions 14 and 15 are first and second input / output portions of the ladder resistor 10, respectively. The ladder resistor 10 is formed on a substrate (not shown) by a known semiconductor manufacturing process.

  In the embodiment of the present invention, the contact regions 14, 15, the first pillar portion 11, the second pillar portion 12, and the ladder portions 13a to 13g use, for example, NiCo, InSb or the like as a resistance wiring material. .

(Adjustment of resistance value of ladder resistor 10)
FIGS. 2A and 2B are diagrams for explaining the operation of trimming the ladder resistor 10 according to the embodiment of the present invention with a laser and adjusting it to a predetermined resistance value.

  As shown to Fig.1 (a), let the resistance value of the part of the 1st pillar part 11, the ladder parts 13a-13g, and the part of the 2nd pillar part 12 be Ra, Rb, and Ra, respectively.

  FIG. 2A is a view showing that the position of the ladder portion 13d has been cut by laser trimming, and FIG. 2B is a circuit diagram corresponding thereto. Here, since the adjustment step capable of adjusting the resistance value by trimming the ladder portion by one step is approximately calculated, Rb is assumed to be small enough to be ignored.

  Under the above conditions, the current I flowing through the trimmed ladder resistor 10 flows as shown in FIG. In this case, the circuit diagram is equivalently represented as shown in FIG. 2B, and the combined resistance is the sum of the series combined resistance 4Ra up to the trimming portion and the parallel combined resistance 2Ra / 2 = Ra after the trimming portion. 5Ra.

  Consider the case of an N-stage ladder resistor in the same way as described above. FIG. 3A is a circuit diagram of a ladder resistor having an N-stage ladder portion, and FIG. 3B is an equivalent circuit diagram when trimming is performed. Consider the combined resistance when the second column part 12 up to the n-th of the N stages is trimmed. Here, if Rb is small enough to be ignored, it is equivalently expressed as shown in FIG. 3B. Therefore, the series combined resistance nRa up to the trimming portion and the parallel combined resistance (N− after the trimming portion) are expressed. n) Combined with Ra / 2, the combined resistance is (N + n) Ra / 2.

  Therefore, in the ladder resistor 10 according to the embodiment of the present invention, the resistance value can be adjusted in steps of Ra / 2 by cutting the ladder portion by one stage by trimming.

(Effect of the embodiment of the present invention)
FIG. 4A shows a ladder resistor having a conventional N-stage ladder portion, and FIG. 4B shows a state in which this ladder portion is cut by n stages by trimming.

  As shown in FIG. 4B, most of the current I ′ flowing through the ladder resistor flows through the (n + 1) -th ladder portion, so that the combined resistance is 2nRa + Rb. Therefore, the resistance value is adjusted in steps of 2Ra by cutting the ladder portion by one stage by trimming.

  Therefore, the resistance value of the ladder resistor according to the embodiment of the present invention can be adjusted with an accuracy four times that of the conventional ladder resistor.

  In addition, the above-described effect can be achieved as a pattern layout in which the line widths of the first pillar portion 11 and the second pillar portion 12 and the ladder portion 13 are different, so that the first pillar portion 11 and the second pillar portion 12 are The line width of the ladder portion 13 can be set larger. Thereby, the ladder part 13 is lengthened by setting the line width of the ladder part 13 to be the same as the conventional one, and setting the line widths of the first pillar part 11 and the second pillar part 12 larger than the conventional one. In addition, the resistance value can be adjusted with higher accuracy.

  As described above, according to the adjustment pattern structure of the ladder resistor 10 according to the embodiment of the present invention, the adjustment can be performed with a fineness four times or more than the conventional ladder resistor adjustment step. Accordingly, since two steps of rough adjustment and fine adjustment are not required, the adjustment time can be shortened, and the resistance value can be adjusted with high accuracy by trimming work in one step. .

  Moreover, if this is applied to an electronic component, the area of the ladder resistor occupying the semiconductor chip can be reduced, and the cost can be reduced.

(Example of application of ladder resistor according to embodiment of present invention to electronic component)
As an electronic component, an example of application to an MR sensor 100 in which a highly accurate offset adjustment is required by adjusting a resistance value will be described.

  The MR sensor 100 detects the change in the magnetic field and the presence / absence of the magnetic substance as a voltage change by utilizing the fact that the resistance value of the resistance part constituting the MR sensor 100 changes due to the magnetic resistance due to the magnetoresistive effect.

  FIG. 5A shows a configuration in which the resistors R1, R2, R3, and R4 are bridge-connected in the horizontal and vertical directions, and the A direction and the B direction of the magnetic field applied to each resistor during trimming adjustment. FIG. 5 is a circuit connection diagram showing a configuration in which resistors R5, R6, R7, and R8 are bridge-connected in an orthogonal 45-degree direction, and a C direction and a D direction of a magnetic field applied to each resistor during trimming adjustment.

  The power supply voltage Vcc1 is supplied to the end where the resistors R1 and R3 are connected, the end where the resistors R2 and R4 are connected is connected to the ground GND, and the output is output from the end where the resistors R1 and R2 are connected. The output voltage Vout1- is output from the end where the voltage Vout1 + and the resistors R3 and R4 are connected.

  Similarly, the power supply voltage Vcc2 is supplied to the end where the resistors R5 and R7 are connected, the end where the resistors R6 and R8 are connected is connected to the ground GND, and the end where the resistors R5 and R6 are connected. Output voltage Vout2 +, and output voltage Vout2- is output from the end where resistors R7 and R8 are connected.

  FIG. 6A is a plan view showing the MR sensor 100 configured by laying out the circuit configuration diagram described above on the substrate 50 in a predetermined pattern, and FIG. 6B shows R1 to R8. It is the elements on larger scale of the ladder resistor 10 formed in a part of.

  Resistors R1 to R8 assembled in the bridge shown in FIG. 3 are formed of a predetermined resistance material on the substrate 50. A ladder resistor 10 shown in FIG. 6B is formed on a part of each of the resistors R1 to R8, and is formed of the same resistance material as the resistors R1 to R8 except for the second column portion 12. . The first column portion 11 and the ladder portion 13 of the resistors R1 to R8 and the ladder resistor 10 are formed by a known semiconductor process using InSb, NiCo, or the like, for example. The second column portion 12 of the ladder resistor 10 is formed of a material having a specific resistance lower than that of InSb, NiCo or the like, for example, Al or an alloy thereof.

NiCo, which has a high electron mobility and is often used as an MR sensor, is used for the resistors R1 to R8 and the first pillar portion 11, the second pillar portion 12 and the ladder portion 13 of the ladder resistor 10, and the specific resistance thereof is about 2. 3 × 10 ⁻⁷ (Ω · m).

  While applying the magnetic fields in the A to D directions shown in FIGS. 5A and 5B to the MR sensor 100 formed as described above, the output voltages Vout1 +, Vout1-, Vout2 +, and Vout2- of the MR sensor 100 are applied. taking measurement. While performing this measurement, laser trimming of the ladder portion 13 of each of the ladder resistors 10 of the resistors R1 to R8 is performed. By adjusting the resistance values of the resistors R1 to R8 with laser trimming, the offsets of the output voltages Vout1 +, Vout1-, Vout2 +, and Vout2- can be adjusted with high accuracy.

  In the case of this MR sensor 100, since the first pillar portion 11 and the second pillar portion 12 are configured with a line width larger than the line width conventionally used, the offset of each of the resistors R1 to R8. Adjustment accuracy has been greatly improved. Specifically, the adjustment accuracy of ± 5 mV in the conventional configuration can be adjusted with an accuracy of ± 1 mV.

(A) is a circuit block diagram which shows the adjustment pattern structure of the ladder resistance which concerns on embodiment of this invention, (b) is a figure which shows the pattern layout of the ladder resistance of (a) formed on the board | substrate. It is. (A) is a figure which shows having cut | disconnected by the laser trimming to the position of the ladder part 13d, (b) is a circuit diagram corresponding to this. (A) is a circuit diagram of a ladder resistor having an N-stage ladder section, and (b) is an equivalent circuit diagram when trimming is performed. (A) shows the ladder resistance which has the conventional N-stage ladder part, (b) is a figure which shows the state which cut | disconnected only this n-stage ladder part by trimming. (A) shows the configuration in which the resistors R1, R2, R3, and R4 are bridge-connected in the horizontal and vertical directions, and the A direction and the B direction of the magnetic field applied to each resistor during trimming adjustment, and (b) is orthogonal FIG. 5 is a circuit connection diagram showing a configuration in which resistors R5, R6, R7, and R8 are bridge-connected in a 45-degree direction, and a C direction and a D direction of a magnetic field applied to each resistor during trimming adjustment. (A) is a top view which shows MR sensor 100 comprised by laying out what was constituted by the above-mentioned circuit connection diagram on substrate 50 by a predetermined pattern, and (b) is one of R1-R8. It is the elements on larger scale of the ladder resistor 10 formed in the part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Ladder resistance 11 1st pillar part 12 2nd pillar part 13, 13a-13g Ladder part 14, 15 Contact area | region 50 Board | substrate 100 MR sensor R1-R8 Resistance

Claims (4)

First and second pillars formed on the substrate;
A plurality of ladder portions formed in parallel between the first and second pillar portions, and
A first input / output unit provided at an end of the first column part;
A second input / output unit provided at an end opposite to the end of the second column part;
A ladder resistance adjustment pattern structure characterized by comprising:   2. The ladder resistor adjustment pattern structure according to claim 1, wherein a pattern width of each of the first and second pillar portions is larger than a pattern width of the ladder resistor. First and second pillars formed on the substrate;
A plurality of ladder portions formed in parallel between the first and second pillar portions, and
A first input / output unit provided at an end portion of the first column portion; and a second input / output unit provided at an end portion on the opposite side of the end portion of the second column portion. Including a ladder resistor having a circuit element;
At least one of the ladder portions of the ladder resistor is subjected to a trimming process for adjusting a resistance value. 4. The electronic component according to claim 3, wherein the adjustment pattern of the ladder resistance is formed so that the pattern width of the first and second column portions is larger than the pattern width of the ladder resistance.

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