KR20150001117A

KR20150001117A - Inertial Sensor

Info

Publication number: KR20150001117A
Application number: KR20130073828A
Authority: KR
Inventors: 한승훈; 김종운; 이성준; 임창현
Original assignee: 삼성전기주식회사
Priority date: 2013-06-26
Filing date: 2013-06-26
Publication date: 2015-01-06

Abstract

An inertial sensor according to an embodiment of the present invention includes a mass body, an electrode or a piezoresistive element, a flexible beam to which the mass is coupled, and a flexible beam connected to the flexible beam, And a package portion covering the sensor portion, and a stress blocking slit is formed in the package portion.

Description

Inertial Sensor

The present invention relates to an inertial sensor.

Generally, inertial sensors are widely used in automobiles, airplanes, mobile communication terminals, toys, etc., and three-axis acceleration and angular velocity sensors for measuring X-axis, Y-axis and Z-axis acceleration and angular velocity are required. In order to detect minute accelerations High performance and small size.

The acceleration sensor according to the related art includes a technical feature for converting the movement of the mass body and the flexible portion into an electric signal and includes a piezo resistor (piezoresistance) detecting the movement of the mass from the resistance change of the piezoresistive element disposed in the flexible portion, And a capacitance type in which the movement of the mass is detected by a change in capacitance between the fixed electrode and the like.

And the piezoresistance method uses a device whose resistance value changes by stress. For example, where the tensile stress is distributed, the resistance value increases and the resistance value decreases where the compressive stress is distributed.

In the inertial sensor according to the prior art including the prior art, when stress is applied due to an external impact or the like, the sensing efficiency is lowered and the sensor may be damaged or the system may be unbalanced. Further, when a separate stress relief structure is formed in order to block the stress due to the stress, there is a problem that the size increases and the productivity decreases.

US 20060156818A

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and it is a first aspect of the present invention to provide a strain relief slit in a package portion of an inertial sensor and a separate stress relief structure such as a buffer layer, And to provide an inertial sensor that can be implemented with reduced weight and productivity can be increased.

According to a second aspect of the present invention, there is provided a stress blocking slit formed on a PCB in addition to a stress blocking slit in a package, and an inertial sensor capable of effectively blocking an external impact by blocking external stress at upper, lower, .

Further, in the inertial sensor according to an embodiment of the present invention, a plurality of the stress blocking slits are formed so as to surround the outer peripheral portion of the sensor portion.

The inertial sensor according to an embodiment of the present invention may further include an upper cover coupled to one side of the sensor unit to cover an electrode or a piezoresistive element of the sensor unit, do.

Further, in the inertial sensor according to an embodiment of the present invention, the sensor further includes a lower cover coupled to the support portion to cover the mass of the sensor portion, and the lower cover is covered by the package portion.

In the inertial sensor according to an embodiment of the present invention, the lower cover is coupled to the PCB, and the PCB is a wiring board for inputting and outputting a sensor signal.

Further, in the inertial sensor according to an embodiment of the present invention, a stress blocking slit is formed in the PCB.

Further, in the inertial sensor according to an embodiment of the present invention, the stress blocking slit may be formed to surround the outer circumferential portion of the sensor portion.

In the inertial sensor according to an embodiment of the present invention, an in / out pad for inputting and outputting signals of the sensor unit may be formed on the PCB.

The features and advantages of the present invention will become more apparent from the following detailed description based on the accompanying drawings.

Prior to this, terms and words used in the present specification and claims should not be construed in a conventional and dictionary sense, and the inventor may appropriately define the concept of a term in order to best describe its invention The present invention should be construed in accordance with the spirit and scope of the present invention.

According to the present invention, there is provided an inertial sensor that can be realized in a small size and light weight and can be increased in productivity, because a stress blocking slit is formed in the package portion of the inertial sensor and a separate stress blocking structure such as a buffer layer is not required The stress blocking slit is formed on the PCB in addition to the stress blocking slit in the package portion, so that the inertia sensor capable of effectively blocking the external impact by blocking the external stress at the upper, lower and side portions of the sensor portion can be obtained.

1 is a sectional view schematically showing the configuration of an inertial sensor according to an embodiment of the present invention;
2 is a schematic plan view of the inertial sensor shown in Fig.
3 is a schematic bottom view of the inertial sensor shown in Fig.

BRIEF DESCRIPTION OF THE DRAWINGS The objectives, specific advantages and novel features of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. It should be noted that, in the present specification, the reference numerals are added to the constituent elements of the drawings, and the same constituent elements are assigned the same number as much as possible even if they are displayed on different drawings. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

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

1 is a schematic plan view of an inertial sensor shown in FIG. 1, and FIG. 3 is a cross-sectional view of the inertial sensor shown in FIG. 1, It is a schematic bottom view.

The inertial sensor 100 includes a sensor unit 110, an upper cover 120 and a lower cover 130, a package unit 140, and a PCB 150, as shown in FIG.

More specifically, the upper cover 120 is coupled to the sensor unit to cover one side of the sensor unit 110, and the lower cover 130 is coupled to the sensor unit 110 to cover the other side of the sensor unit 110. [ (Not shown).

The package unit 140 is coupled to the PCB 150 to cover the sensor unit 110, the upper cover 120, and the lower cover 130. A stress blocking slit 141 for blocking external stress is formed in the package unit 140.

As shown in FIGS. 1 and 2, a plurality of the stress blocking slits 141 may be formed to surround the outer circumferential portion of the sensor portion 110. This is to prevent the stress generated from the outside from being transmitted to the sensor unit, and to be reduced or exhausted by the slit.

Also, the PCB 150 is a wiring board for inputting and outputting a sensor signal, and the lower cover 130 is coupled to be laminated. An in / out pad 152 for inputting and outputting a sensor signal is formed on the PCB 150, and a stress blocking slit 151 is formed.

1 and 3, at least one stress blocking slit 151 may be formed so as to surround the outer circumferential portion of the sensor portion 110, and the stress generated from the outside may not be transmitted to the sensor portion And is to be reduced or exhausted by the slit.

1, the inertial sensor 100 according to an embodiment of the present invention includes a stress blocking slit 141 formed on a package portion 140 and a stress blocking slit 151 formed on a PCB 150 The external stress can be effectively blocked by intercepting the external stress at the upper, lower, and side portions of the sensor unit 110.

In addition, since a separate stress relief structure such as a buffer layer is not required, it can be realized in a small size and light weight, and the productivity is increased.

Next, the sensor unit 110 includes a mass body 111, a flexible beam 112, and a support unit 113.

In addition, a driving electrode and a sensing electrode are formed on one surface of the flexible beam 112 to be realized by an angular velocity sensor, a piezoresistive element (not shown) is coupled to be realized as an acceleration sensor, . The flexible beam 112 may be formed with an electrode pad 114 for inputting and outputting a sensor signal by wire bonding or the like.

The support portion 113 is coupled to the other surface of the flexible beam 112 to support the flexible beam 112 so that the mass body 111 can float.

When the external force is generated, the mass body 111 generates a moment by an external force and is moved. A piezoresistive element (not shown) of the flexible beam 112 composed of a flexible board is mounted on the mass body 111, The resistance value is changed by detecting the resistance value, and the acceleration is calculated.

Also, as described above, the top cover 120 is coupled to one side of the flexible beam 112 to cover the driving and sensing electrodes or the piezoresistive element. A bonding agent B may be applied to bond the upper cover to the flexible beam 112 and the thickness of the bonding agent B may affect the flexibility of the flexible beam 120 and the upper cover 120. [ The interval can be determined.

Further, as described above, the lower cover 130 is coupled to one surface of the support portion 113 to cover the mass body 111. [ The bonding agent B may be applied to the support portion 113 to bond the lower cover 130 and the mass body 111 and the lower cover 130 may be bonded to each other by the thickness of the bonding agent B. [ Can be determined.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the same is by way of illustration and example only and is not to be construed as limiting the present invention. It is obvious that the modification and the modification are possible.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

100: inertia sensor 110: sensor unit
120: upper cover 130: lower cover
140: Package Unit 150: PCB
111: mass body 112: flexible beam
113: Support part 114: Electrode pad
141: stress blocking slit 151: stress blocking slit
152: in / out pad B: bonding agent

Claims

A sensor unit including a mass, a flexible beam arranged with an electrode or a piezoresistive element and coupled with the mass, and a support connected to the flexible beam and supporting a flexible beam such that the mass is lifted; And
And a package portion covering the sensor portion,
And a stress blocking slit is formed in the package portion.

The method according to claim 1,
Wherein a plurality of the stress blocking slits are formed so as to surround the outer peripheral portion of the sensor portion.

The method according to claim 1,
Further comprising an upper cover coupled to one side of the sensor unit to cover the electrode of the sensor unit or the piezoresistive element, and the upper cover is covered by the package unit.

The method according to claim 1,
Further comprising a lower cover coupled to the support portion to cover the mass of the sensor portion, wherein the lower cover is covered by the package portion.

The method of claim 4,
Further comprising a printed circuit board (PCB) to which the lower cover is coupled and which is a wiring board for inputting and outputting a sensor signal.

The method of claim 5,
Wherein the PCB is provided with a stress blocking slit.

The method of claim 6,
Wherein at least one of the stress blocking slits is formed to surround an outer peripheral portion of the sensor portion.

The method of claim 5,
And an input / output pad for signal input / output of the sensor unit is formed on the PCB.