CN115329707A - Design method of angle sensing chip based on anisotropic magnetoresistance effect - Google Patents
Design method of angle sensing chip based on anisotropic magnetoresistance effect Download PDFInfo
- Publication number
- CN115329707A CN115329707A CN202210977713.8A CN202210977713A CN115329707A CN 115329707 A CN115329707 A CN 115329707A CN 202210977713 A CN202210977713 A CN 202210977713A CN 115329707 A CN115329707 A CN 115329707A
- Authority
- CN
- China
- Prior art keywords
- pad
- bridge
- magnetic resistance
- angle
- layout
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/30—Circuit design
- G06F30/39—Circuit design at the physical level
- G06F30/392—Floor-planning or layout, e.g. partitioning or placement
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/30—Circuit design
- G06F30/39—Circuit design at the physical level
- G06F30/398—Design verification or optimisation, e.g. using design rule check [DRC], layout versus schematics [LVS] or finite element methods [FEM]
Abstract
The invention discloses a design method of an angle sensing chip based on an anisotropic magnetoresistance effect, the angle sensing chip can realize double-angle sine and cosine waveform signals with a phase difference of 45 degrees, the sensing range is 0-180 degrees, the uniqueness at a certain angle can be ensured, and the double-bridge arrangement uses a concentric design, so that the sensing error can be reduced, the sensing precision is improved, and the accurate measurement of the angle is realized; and the double bridges are concentrically arranged, so that the overall size of the chip is effectively reduced, the purpose of miniaturization of devices is realized, and the production cost of products is greatly reduced.
Description
Technical Field
The invention relates to the technical field of angle sensing chips, is mainly used for measuring the rotation angle of an article to be measured, can be applied to the fields of robots, industrial automation control, aerospace and the like, and particularly relates to a method for designing an angle sensing chip based on an anisotropic magnetoresistance effect.
Background
The angle sensing chip is a signal sensing device for measuring an included angle between an object to be measured and a reference object, and is mainly divided into a photoelectric angle sensor and a magnetic angle sensor according to different principles. The photoelectric angle sensor is limited by the processing precision, so that the precision is not high. The high-end angle sensors in the current market all belong to magnetic angle encoders based on magnetic signal detection. According to different magnetic induction principles, there are mainly: the TMR type, the AMR type and the GMR type are mainly different in the shape and the structure of an angle sensing chip pattern of different manufacturers.
Disclosure of Invention
The invention aims to provide a design method of an angle sensing chip based on an anisotropic magnetoresistance effect, the angle sensing chip can realize double-angle sine and cosine waveform signals with the phase difference of 45 degrees, the sensing range is 0-180 degrees, the uniqueness at a certain angle can be ensured, and the double-bridge arrangement and the concentric design can reduce the sensing error, improve the sensing precision and realize the accurate measurement of the angle; and the double-bridge concentric arrangement also effectively reduces the whole size of the chip, realizes the purpose of miniaturization of devices, greatly reduces the production cost of products and overcomes the defects of the prior art.
In order to achieve the purpose, the invention provides the following technical scheme: a design method of an angle sensing chip based on anisotropic magnetoresistance effect comprises the whole design part of the chip layout and the arrangement structure of a Wheatstone bridge;
the AMR angle sensing chip layout comprises two Wheatstone bridges, namely a bridge A and a bridge B; the bridge A and the bridge B are concentrically arranged, and the two bridges and an external circuit are connected with PADs; defining an external magnetic field H as a direction x, wherein the direction x is 0 degrees, every two resistors in the bridge A are sequentially parallel to the direction x and the direction y, and adjacent resistors in the bridge A form an included angle of 90 degrees; four groups of resistors in the bridge B form 45-degree included angles with the x direction and the y direction, and adjacent resistors in the bridge B form 90-degree included angles;
an arrangement of the wheatstone bridges; resistors with an included angle of 90 degrees in the electric bridge A are communicated, and four resistor units in the electric bridge A are arranged according to the central position of the layout and are in a four-corner windmill shape; wherein the connection position of two resistors of the bridge A is connected to the PAD; the four resistance units of the electric bridge B are respectively arranged in four areas at four corners of a square of the AMR angle sensing chip layout according to the rest positions of the four resistance units of the electric bridge A after the arrangement is finished, and adjacent resistance parts in the electric bridge B are communicated and connected to the PAD; the centers of the magnetic resistance patterns of the electric bridge A and the electric bridge B are positioned at the same position, namely the center of the layout; the concentric arrangement not only greatly reduces the whole size of the chip, but also realizes the purpose of miniaturization of the device; and the measurement error of the chip can be effectively reduced, and the measurement precision of the angle sensor chip is improved.
As a further scheme of the invention: the layout of the AMR angle sensing chip is designed to be a square with the side length of 700-1000 um; the distance between the bridge part and the layout boundary is 4 um-10 um.
As a further scheme of the invention: the PAD material is Al electrodes, the number of the PAD materials is 6, and the PAD materials are respectively PAD 1 、PAD 2 、PAD 3 、PAD 4 、PAD 5 And PAD 6 (ii) a Wherein PAD 1 And PAD 5 、PAD 2 And PAD 6 、PAD 3 And PAD 4 And performing mirror symmetry on every two layout centers. Wherein PAD1 and PAD5 are the common PAD of bridge A and bridge B, PAD 5 For double bridge input VCC, PAD 1 Is the ground end GND, PAD of the double bridge 2 And PAD 6 The positive voltage output end (VOUTB +) and the negative voltage output end (VOUTB-) of the bridge B are sequentially arranged; PAD 3 And PAD 4 The positive voltage output terminal (VOUTA +) and the negative voltage output terminal (VOUTA-) of the bridge A are arranged in sequence.
As a further scheme of the invention: the length-width ratio of the magnetic resistance layer of each magnetic resistance unit in the bridge is 100-200 magnetic resistance strips, the magnetic resistance strips of each unit are arranged in order, and the magnetic resistance strips of each resistor unit are connected end to form a snake shape; the width w of the magnetic resistance strips is kept between 5um and 20um according to the design value of actual requirements, the thickness t of the magnetic resistance strip film is between 15nm and 50nm, and the distance d between the magnetic resistance strips is between 2um and 5um.
As a further scheme of the invention: the whole chip structure is divided into 5 layers; wherein the substrate adopts single crystal Si in a standard CMOS process; an isolation layer is arranged on the substrate and is formed by thermal oxidation process SiO with the thickness of 250nm-500nm 2 Composition is carried out; the via hole metal is made of Al material and has the thickness of 1-2 um, and electrode Al is grown on the Sensor layer by etching SiN after the photoetching process, so that the Sensor layer is conducted and can be connected with the PAD part; the Sensor layer is made of permalloy material and has a thickness of 20nm-50nm.
Compared with the prior art, the invention has the beneficial effects that: the invention can output sine and cosine waveform signals with a double angle of phase difference of 45 degrees, namely, the uniqueness of the sensing angle is ensured, and the accurate measurement of the angle is realized. Through the concentric arrangement design and scientific layout of the double Wheatstone bridges, the structure is simplified, the whole area and the processing process flow of the chip are reduced as much as possible while the chip parameters meet the requirements, so that the production and manufacturing cost is effectively reduced, and the product quality is improved.
Drawings
FIG. 1 is an output characteristic diagram of an AMR angle sensor chip according to the present invention;
FIG. 2 is a schematic diagram of an AMR angle sensor chip layout according to the present invention;
FIG. 3 is a schematic diagram of an AMR angle sensor chip according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1-3, the present invention provides a technical solution: a design scheme of an angle sensing chip based on Anisotropic Magnetoresistance (AMR) comprises an integral design part of a layout of the angle sensing chip, arrangement of a Wheatstone bridge, shape and size design of resistors of the Wheatstone bridge and an angle sensing chip structure.
According to the output characteristics of the film, when the external magnetic field H is defined to be 0 DEG direction in the x direction, the bridge A outputs a cosine signal y with double angle A ＝k 1 cos (2 theta), bridge B outputs a double-angle sine signal y B ＝k 2 sin (2 θ), k for a particular chip 1 、k 2 Is a known constant. As shown in FIG. 1, for a particular angle, the outputs of both bridges are unique, and the actual measurements can be converted from the outputs of both bridgesAnd measuring the angle.
The AMR angle sensing chip layout comprises: bridge A, bridge B, bridge A and bridge B arrange concentrically, 6 PADs that the bridge is connected with external circuit. As shown in fig. 2, the four sets of resistors of the bridge a are respectively parallel to the x and y directions and form 90 ° angles with each other, and the four sets of resistors of the bridge B form 45 ° angles with the x and y directions and form 90 ° angles with each other.
The thin film part of the AMR angle sensing chip mainly comprises a magnetic resistance line and an electrode. According to different line resistance requirements, the overall size of the layout can be designed to be a square with side length (700-1000) um. The distance between the bridge part and the layout boundary is 4-10 um. The resistance parts of the bridge A with an included angle of 90 degrees are communicated, and four resistor units are arranged according to the central position of the layout to form a four-corner windmill shape and are connected to the PAD. And the four resistance units of the bridge B are respectively arranged in four areas at four corners of a square according to the rest positions of the four resistance units of the bridge A after arrangement, and all resistance parts in the bridge B are communicated and connected to the PAD. The centers of the magnetoresistive patterns of the bridge A and the bridge B are positioned at the same position, namely the center of the layout. The concentric arrangement not only greatly reduces the whole size of the chip, but also realizes the purpose of miniaturization of the device; and the measuring error of the chip can be effectively reduced, and the measuring precision of the angle sensor chip is improved. The 6 square structures are PADs which are connected with the electric bridge and an external circuit, the PADs are made of Al electrodes, the size of the PADs is 80um to 80um, the size of the PADs is designed to be convenient for packaging and routing, and the actual size of the PADs can be properly increased and decreased according to a packaging process. PAD 1 And PAD 5 、PAD 2 And PAD 6 、PAD 3 And PAD 4 And performing mirror symmetry on every two layout centers. Wherein, PAD 1 And PAD 5 Is a common PAD, PAD of bridge A and bridge B 5 Is a dual bridge input terminal (VCC), PAD 1 Ground (GND), PAD, of a double bridge 2 And PAD 6 A positive voltage output terminal (VOUTB +) and a negative voltage output terminal (VOUTB-) of the bridge B are respectively arranged; PAD 3 And PAD 4 Respectively as the positive voltage output terminal (VOUTA +) and the negative voltage output terminal (VOUTA-) of the bridge A.
According to the AMR principle of the NiFe film, the magnetic moment of the film can be distributed along the long edge direction, the magnetic resistance layer is designed into magnetic resistance strips with the length-width ratio of 100-200, the magnetic resistance strips of each unit are arranged in order, and the magnetic resistance strips of each resistor unit are connected end to form a snake shape. The width w of the magnetic resistance strips is kept between 5um and 20um according to the design value of actual requirements, the thickness t of the magnetic resistance strip film is between 15nm and 50nm, and the distance d between the magnetic resistance strips is between 2um and 5um. The structure of the AMR angle sensor has a total of 5 layers, as shown in fig. 3. Wherein the substrate adopts single crystal Si in a standard CMOS process; the isolation layer is composed of SiO2 with the thickness of 250nm-500nm by a thermal oxidation process; the via hole metal is made of Al material and has the thickness of 1-2 um, and electrode Al is grown on the Sensor layer by etching SiN after the photoetching process, so that the Sensor layer is conducted and can be connected with the PAD part; the Sensor layer is made of permalloy material and has a thickness of 20nm-50nm.
Those not described in detail in this specification are within the skill of the art.
Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various changes in the embodiments and/or modifications of the invention can be made, and equivalents and modifications of some features of the invention can be made without departing from the spirit and scope of the invention.
Claims (5)
1. A design method of an angle sensing chip based on an anisotropic magnetic resistance effect is characterized in that: the method comprises the whole design part of the chip layout and the arrangement structure of a Wheatstone bridge;
the AMR angle sensing chip layout comprises two Wheatstone bridges, namely a bridge A and a bridge B; the bridge A and the bridge B are concentrically arranged, and the two bridges and an external circuit are connected with PADs; defining an external magnetic field H as a direction x, wherein the direction x is 0 degrees, every two resistors in the bridge A are sequentially parallel to the direction x and the direction y, and adjacent resistors in the bridge A form an included angle of 90 degrees; four groups of resistors in the bridge B form 45-degree included angles with the x direction and the y direction, and adjacent resistors in the bridge B form 90-degree included angles;
an arrangement of the wheatstone bridges; resistors with an included angle of 90 degrees in the electric bridge A are communicated, and four resistor units in the electric bridge A are arranged according to the central position of the layout and are in a four-corner windmill shape; wherein the connection position of two resistors of the bridge A is connected to the PAD; the four resistance units of the electric bridge B are respectively arranged in four areas at four corners of a square of the AMR angle sensing chip layout according to the rest positions of the four resistance units of the electric bridge A after the arrangement is finished, and adjacent resistance parts in the electric bridge B are communicated and connected to the PAD; the centers of the magnetic resistance patterns of the electric bridge A and the electric bridge B are positioned at the same position, namely the center of the layout; the concentric arrangement not only greatly reduces the whole size of the chip, but also realizes the purpose of miniaturization of the device; and the measurement error of the chip can be effectively reduced, and the measurement precision of the angle sensor chip is improved.
2. The method for designing an angle sensor chip based on the anisotropic magnetic resistance effect according to claim 1, wherein: the layout of the AMR angle sensing chip is designed to be a square with the side length of 700-1000 um; the distance between the bridge part and the layout boundary is 4-10 um.
3. The method for designing an angle sensor chip based on the anisotropic magnetic resistance effect according to claim 1, wherein: the PAD material is Al electrodes, the number of the PAD materials is 6, and the PAD materials are respectively PAD 1 、PAD 2 、PAD 3 、PAD 4 、PAD 5 And PAD 6 (ii) a Wherein PAD 1 And PAD 5 、PAD 2 And PAD 6 、PAD 3 And PAD 4 And performing mirror symmetry on every two layout centers. Wherein PAD1 and PAD5 are the common PAD of bridge A and bridge B, PAD 5 For double bridge input VCC, PAD 1 Is the ground end GND, PAD of the double bridge 2 And PAD 6 The positive voltage output end (VOUTB +) and the negative voltage output end (VOUTB-) of the bridge B are sequentially arranged; PAD 3 And PAD 4 The positive voltage output terminal (VOUTA +) and the negative voltage output terminal (VOUTA-) of the bridge A are arranged in sequence.
4. The method for designing an angle sensor chip based on the anisotropic magnetic resistance effect according to claim 1, wherein: the length-width ratio of the magnetic resistance layer of each magnetic resistance unit in the bridge is 100-200 magnetic resistance strips, the magnetic resistance strips of each unit are arranged in order, and the magnetic resistance strips of each resistor unit are connected end to form a snake shape; the width w of the magnetic resistance strips is kept between 5um and 20um according to the design value of actual requirements, the thickness t of the magnetic resistance strip film is between 15nm and 50nm, and the distance d between the magnetic resistance strips is between 2um and 5um.
5. The method for designing an angle sensor chip based on the anisotropic magnetic resistance effect according to claim 1, wherein: the whole chip structure is divided into 5 layers; wherein the substrate adopts single crystal Si in a standard CMOS process; an isolation layer is arranged on the substrate and is formed by thermal oxidation process SiO with the thickness of 250nm-500nm 2 Composition is carried out; the via hole metal is made of Al material and has the thickness of 1-2 um, and electrode Al is grown on the Sensor layer by etching SiN after the photoetching process, so that the Sensor layer is conducted and can be connected with the PAD part; the Sensor layer is made of permalloy material and has a thickness of 20nm-50nm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210977713.8A CN115329707A (en) | 2022-08-15 | 2022-08-15 | Design method of angle sensing chip based on anisotropic magnetoresistance effect |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210977713.8A CN115329707A (en) | 2022-08-15 | 2022-08-15 | Design method of angle sensing chip based on anisotropic magnetoresistance effect |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115329707A true CN115329707A (en) | 2022-11-11 |
Family
ID=83923381
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210977713.8A Pending CN115329707A (en) | 2022-08-15 | 2022-08-15 | Design method of angle sensing chip based on anisotropic magnetoresistance effect |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115329707A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116699482A (en) * | 2023-08-08 | 2023-09-05 | 北京智芯微电子科技有限公司 | Magnetic sensor and anti-fraudulent use electric energy meter |
-
2022
- 2022-08-15 CN CN202210977713.8A patent/CN115329707A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116699482A (en) * | 2023-08-08 | 2023-09-05 | 北京智芯微电子科技有限公司 | Magnetic sensor and anti-fraudulent use electric energy meter |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN202119391U (en) | Independent packaged magneto-resistor angle sensor | |
| WO2012116659A1 (en) | Separately packaged bridge magnetic-field angle sensor | |
| EP3029479B1 (en) | Singlechip push-pull bridge type magnetic field sensor | |
| US9964601B2 (en) | Magnetic sensor | |
| CN205809273U (en) | A kind of anisotropic magnetoresistance AMR sensor without set/reset device | |
| JP2796391B2 (en) | Physical quantity detection method and physical quantity detection device, servo motor using these methods and devices, and power steering device using this servo motor | |
| KR20150102053A (en) | Magnetic Sensing Device and Magnetic Sensing Method Therefor | |
| CN100375890C (en) | Magnetic displacement sensor containing zero-setting GMR chip | |
| CN115267623B (en) | Magneto-resistance magnetic switch sensor | |
| WO2012031553A1 (en) | Magnetic encoder with tunnel magnetoresistance effect | |
| CN115329707A (en) | Design method of angle sensing chip based on anisotropic magnetoresistance effect | |
| WO2022183826A1 (en) | Magnetic sensor and manufacturing method therefor, and electronic device | |
| CN111044953A (en) | Single-chip full-bridge TMR magnetic field sensor | |
| TWI685667B (en) | Magnetic field sensing apparatus | |
| US20130127454A1 (en) | Magnetic field sensor including an anisotropic magnetoresistive magnetic sensor and a hall magnetic sensor | |
| JP2015108527A (en) | Magnetic sensor | |
| JP6185298B2 (en) | Magnetic sensor | |
| EP3814722A1 (en) | A magnetic encoder | |
| CN116182696A (en) | Magneto-resistance angle sensor based on anisotropic effect | |
| CN214585084U (en) | Magnetic sensor and nondestructive testing device based on magnetic sensor | |
| JP2005069744A (en) | Magnetic detection element | |
| CN212008887U (en) | Single-chip full-bridge TMR magnetic field sensor | |
| CN206038743U (en) | Single -chip magneto resistor current sensor | |
| JP3004926B2 (en) | Magnetic encoder | |
| CN210142177U (en) | Magnetic field sensing device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |