CN106546931A - A kind of miniature non-diagonal giant magnetoresistance effect sensing element - Google Patents

Abstract

The invention discloses a kind of non-diagonal giant magnetoresistance effect sensing element, including：Coil top layer portion, coil floor portions, sensitive material body, connection via, PCB upper stratas and PCB lower floors；The sensitive material body is arranged between the PCB upper stratas and the PCB lower floors；The coil top layer portion is arranged at PCB upper stratas upper surface；The coil floor portions are arranged at the PCB lower surfaces；The connection via passes through the PCB upper stratas and the PCB lower floors, and connects the coil top layer portion and coil floor portions composition MEMS coils, so as to surround the sensitive material body；Insulation filler is filled between the PCB upper stratas and the PCB lower floors.Instant invention overcomes because the drawbacks of sensing element volume is larger caused by general technology winding volume is excessive, planarizing non-diagonal giant magnetoresistance effect sensing element.

Description

A Miniature Off-Diagonal Giant Magneto-impedance Effect Sensitive Element

technical field

The invention relates to the field of magnetic sensitive elements, in particular to a MEMS magneto-impedance effect sensitive element.

Background technique

The off-diagonal GMI magnetic sensor has a high magnetic field resolution (up to 10 ^-12 T), and can be applied to many aspects such as biological information detection, magnetic safety detection, nondestructive flaw detection, geomagnetic navigation, traffic control, etc. The off-diagonal GMI magnetic sensitive element has the highest resolution in the existing miniaturized (size less than 10mm*10mm*10mm) magnetic field sensors. However, because there is a signal pickup coil in its structure, the miniaturization of its size is restricted by the size of the coil. Therefore, the size of the non-diagonal GMI magnetic sensor cannot be as small as the size of a chip like the Hall element. This limits its application in some occasions.

Therefore, there is an urgent need to design a new non-diagonal GMI magnetic sensor in the market.

Contents of the invention

The invention proposes a miniature non-diagonal giant magneto-impedance effect sensitive element. The signal pick-up coil and sensitive material of the sensitive element are manufactured by the wiring technology of a printed circuit, and the miniaturization of the non-diagonal giant magneto-impedance effect sensitive element is realized.

The miniature non-diagonal giant magneto-impedance effect sensitive element proposed by the present invention includes: a coil top layer part, a coil bottom layer part, a sensitive material body, connection vias, a PCB upper layer and a PCB lower layer; the sensitive material body is arranged on the PCB upper layer and the PCB lower layer; the coil top layer part is arranged on the upper surface of the PCB upper layer; the coil bottom layer part is arranged on the lower surface of the PCB lower layer; the connection via hole passes through the PCB upper layer and the The lower layer of the PCB is connected to the top layer of the coil and the bottom layer of the coil to form a MEMS coil, which surrounds the sensitive material body; an insulating filler is filled between the upper layer of the PCB and the lower layer of the PCB.

In the miniature non-diagonal giant magneto-impedance effect sensitive element proposed by the present invention, the sensitive material body is a material with magneto-impedance effect.

In the miniature non-diagonal giant magneto-impedance effect sensitive element proposed by the present invention, the upper layer of the PCB and the lower layer of the PCB are rigid materials or flexible materials.

In the miniature non-diagonal giant magneto-impedance effect sensitive element proposed by the present invention, the shape of the sensitive material body is film, block or filament.

In the miniature non-diagonal giant magneto-impedance effect sensitive element proposed by the present invention, the wire diameter and the spacing between the wires of the MEMS coil are the minimum wire diameter and wire distance of the circuit board.

In the miniature non-diagonal giant magneto-impedance effect sensitive element proposed by the present invention, the outer surface of the miniature non-diagonal giant magneto-impedance effect sensitive element is covered with an insulating covering layer.

In the miniature non-diagonal giant magneto-impedance effect sensitive element proposed by the present invention, an AC drive signal is applied to both ends of the sensitive material body.

In the miniature non-diagonal giant magneto-impedance effect sensitive element proposed by the present invention, sensor signals are obtained from both ends of the MEMS coil.

In the miniature non-diagonal giant magneto-impedance effect sensitive element proposed by the present invention, the bottom part of the coil is arranged obliquely, its upper end is opposite to the upper end of the corresponding part of the wire at the top layer of the coil, and its lower end is opposite to the other phase of the top layer of the coil. The lower ends of the adjacent parallel wires are opposite.

The purpose of the present invention is to provide a miniature non-diagonal giant magneto-impedance effect sensitive element and its preparation method. The preparation method of the present invention adopts some micro-mechanical preparation methods to overcome the size problem caused by the coil and can well widen the non-diagonal The application of GMI magnetic sensitive components in the field of miniaturization of sensitive components is required.

The invention overcomes the disadvantage of large volume of the sensitive element caused by the large volume of the general process coil, and makes the non-diagonal giant magneto-impedance effect sensitive element planarized.

Description of drawings

Fig. 1 is a top view of a miniature non-diagonal giant magneto-impedance effect sensitive element of the present invention.

Fig. 2 is a cross-sectional view of a miniature non-diagonal giant magneto-impedance effect sensitive element of the present invention.

detailed description

The present invention will be further described in detail in conjunction with the following specific embodiments and accompanying drawings. The process, conditions, experimental methods, etc. for implementing the present invention, except for the content specifically mentioned below, are common knowledge and common knowledge in this field, and the present invention has no special limitation content.

The present invention proposes a miniature non-diagonal giant magneto-impedance effect sensitive element, comprising: coil top layer part 1, coil bottom layer part 2, sensitive material body 3, connection via hole 4, PCB upper layer 5 and PCB lower layer 6.

In the present invention, the sensitive material body 3 is arranged between the PCB upper layer 5 and the PCB lower layer 6, and the sensitive material body 3 is a material with magnetoresistance effect.

In the present invention, the coil top layer part 1 is arranged on the upper surface of the PCB upper layer 5; the coil bottom layer part 2 is arranged on the lower surface of the PCB lower layer 6; The lower end is opposite to the lower end of another adjacent parallel wire b of the top layer part 1 of the coil.

In the present invention, the connection via hole 4 passes through the upper layer 5 of the PCB and the lower layer 6 of the PCB, and connects the coil top layer 1 and the coil bottom layer 2 to form a MEMS coil, thereby surrounding the sensitive material body 3 .

In the present invention, in the present invention, the upper PCB layer 5 and the lower PCB layer 6 are rigid materials or flexible materials, and insulating fillers 7 are filled between the upper PCB layer 5 and the lower PCB layer 6 .

In the present invention, the shape of the sensitive material body 3 is film, block or filament.

In the present invention, the sensor signal 10 is obtained from both ends of the MEMS coil.

In the present invention, the AC driving signal 9 is applied to both ends of the sensitive material body 3 .

In the present invention, the minimum wire diameter and the minimum spacing between the wires of the MEMS coil are the minimum wire diameter and wire distance of the circuit board.

In the present invention, the outer surface of the miniature non-diagonal giant magneto-impedance effect sensitive element is covered with an insulating covering layer 8 .

The non-diagonal GMI magnetic sensitive element shown in Figure 1 adopts the structure of a coil covered by a sensitive material body, wherein the AC drive signal 9 is added to both ends of the sensitive material body 3, and the sensor signal is transmitted from the two ends of the top layer part 1 of the coil and the bottom layer part 2 of the coil. obtained at the end.

As shown in the cross-sectional view of the sensitive element in FIG. 2 , the preparation process is as follows: firstly, the coil top layer part 1 is prepared on the upper surface of the PCB upper layer 5 , and then the sensor material body 3 is prepared on the lower surface of the PCB upper layer 5 .

As shown in FIG. 2 , the cross section of the sensitive material body 3 is prepared parallel to the coil top layer 1 and the coil bottom layer 2 , the length is shorter than the coil and located in the coil top layer 1 and the coil bottom layer 2 . The other end of the sensitive material body 3 is directly connected to the PCB lower layer 6 . The gap between PCB upper layer 5 and PCB lower layer 6 is filled with insulating filling material 7 to fix the whole structure. The bottom coil part 2 is prepared on the lower surface of the lower PCB layer 6 corresponding to the coil top layer part 1 .

As shown in FIG. 1 , the coil bottom part 2 is arranged obliquely, its upper end is opposite to the upper end of the corresponding part of the wire a of the coil top part 1, and its lower end is opposite to the lower end of another adjacent parallel wire b of the coil top part 1. These opposite wire terminals are connected through via holes 4 , and this structure is repeated to form a complete solenoid MEMS coil, surrounding the sensitive material body 3 . Finally, an insulating covering layer 8 is coated on the entire outer surface of the device to complete the preparation of the MEMS giant magneto-impedance effect sensitive element.

The protection content of the present invention is not limited to the above embodiments. Without departing from the spirit and scope of the inventive concept, changes and advantages conceivable by those skilled in the art are all included in the present invention, and the appended claims are the protection scope.

Claims (9)

1. A miniature non-diagonal giant magneto-impedance effect sensitive element, characterized in that it comprises: coil top layer part (1), coil bottom layer part (2), sensitive material body (3), connection via hole (4), PCB The upper layer (5) and the lower layer of the PCB (6); The sensitive material body (3) is arranged between the PCB upper layer (5) and the PCB lower layer (6); The coil top layer part (1) is arranged on the upper surface of the PCB upper layer (5); The coil bottom layer part (2) is arranged on the lower surface of the PCB lower layer (6); The connection via hole (4) passes through the PCB upper layer (5) and the PCB lower layer (6), and connects the coil top layer part (1) and the coil bottom layer part (2) to form a MEMS coil, thereby enclosing said body of sensitive material (3); An insulating filler (7) is filled between the PCB upper layer (5) and the PCB lower layer (6). 2. The miniature non-diagonal giant magneto-impedance effect sensitive element according to claim 1, characterized in that, the sensitive material body (3) is a material with magneto-impedance effect. 3. The miniature non-diagonal giant magneto-impedance effect sensitive element according to claim 1, characterized in that, the PCB upper layer (5) and the PCB lower layer (6) are rigid materials or flexible materials. 4. The miniature non-diagonal giant magneto-impedance effect sensitive element according to claim 1, characterized in that, the shape of the sensitive material body (3) is thin film, block or filament. 5. miniature non-diagonal giant magneto-impedance effect sensitive element as claimed in claim 1, is characterized in that, the minimum diameter of the wire of described MEMS coil and the minimum spacing between the wire are the minimum wire diameter and line distance of circuit board . 6. The miniature non-diagonal giant magneto-impedance effect sensitive element according to claim 1, characterized in that, the outer surface of the miniature off-diagonal giant magneto-impedance effect sensitive element is covered with an insulating covering layer (8). 7. The miniature non-diagonal giant magneto-impedance effect sensitive element according to claim 1, characterized in that an AC drive signal (9) is applied to both ends of the sensitive material body (3). 8. The miniature non-diagonal giant magneto-impedance effect sensitive element according to claim 1, characterized in that the sensor signal (10) is obtained from both ends of the MEMS coil. 9. miniature non-diagonal giant magneto-impedance effect sensitive element as claimed in claim 1, is characterized in that, its upper end of described coil bottom layer part (2) and described coil top layer part (1) corresponding part wire (a) upper end On the contrary, its lower end is opposite to the lower end of another adjacent parallel wire (b) of the coil top layer part (1).