CN103151220B

CN103151220B - Long-contact time micro-electromechanical universal inertia switch and manufacturing method for same

Info

Publication number: CN103151220B
Application number: CN201310062983.7A
Authority: CN
Inventors: 刘双杰
Original assignee: Shenyang Ligong University
Current assignee: Shenyang Ligong University
Priority date: 2013-02-28
Filing date: 2013-02-28
Publication date: 2014-11-19
Anticipated expiration: 2033-02-28
Also published as: CN103151220A

Abstract

The invention provides a long-contact time micro-electromechanical universal inertia switch and a manufacturing method for the same, and aims to solve the problems of capability of capturing inertial acceleration in a single direction only and short contact time of a movable electrode and a fixed electrode of the conventional micro-electromechanical system (MEMS) inertia switch. Key points are that a middle structural layer of a silicon chip comprises an annular mass frame, an annular external electrode and an anchorage area, which are arranged outwards from an anchorage point taken as the center of a circle. The anchorage area and the anchorage point are bonded with a lower cover plate. Four external springs are arranged crosswise. The two ends of each external spring are fixedly arranged between the anchorage area and the annular external electrode respectively. Four internal springs are arranged crosswise. The two ends of each internal spring are fixedly arranged on the annular mass frame and the anchorage point respectively. The inertia switch and the manufacturing method have the positive effects that inertial acceleration in any direction can be captured; and after threshold acceleration is captured, the contact time of the two electrodes is greatly prolonged.

Description

Micro electronmechanical universal inertia switch and manufacture method thereof that time of contact is long

Technical field

The present invention relates to microcontroller switch, be specifically related to micro electronmechanical (MEMS) inertia switch.

Background technology

Micro electro mechanical inertia switch is the sensitive of acceleration to be provided to the MEMS actuator of switch closed action, also claims threshold switch, acceleration switch or g value switch, and it is by the product of machinery and the unified combination of electricity.Not only volume is little, response is fast for MEMS inertia switch, can catch faint signal, and processing performance is good, is applicable to batch production, cuts down finished cost.Micro electro mechanical inertia switch is generally to form hamburger structure by three layers of upper substrate (hereinafter referred to as upper cover plate)-silicon chip intermediate structure layer-infrabasal plates (hereinafter referred to as lower cover), silicon chip intermediate structure layer comprises spring, mass and external electrode, mass wherein connects by spring, become movable electrode, another electrode is fixed electrode.The problem that it exists is:

1, switch can only catch unidirectional inertial acceleration.When needing the inertial acceleration of perception multiple directions, can only realize by switch arrays, but after array switch can not guarantee the consistent and array of the sensitivity of each angle, volume is larger, reliability is lower;

2, the operation principle of micro electro mechanical inertia switch is to move to a certain position after catching acceleration by movable electrode, and fixed electrode collides and then connects circuit.But because the moment of collision is extremely of short duration, make the time of contact of movable electrode and fixed electrode too short, when operational environment is more extreme, (below subzero 30 degree), cause circuit reliably not connect.Therefore how extending the time of contact of two electrodes, is a problem of micro electro mechanical inertia switch.

Summary of the invention

For solving the problems of the technologies described above, the object of this invention is to provide long micro electronmechanical universal (any direction) inertia switch and manufacture method thereof of a kind of time of contact.

The object of the present invention is achieved like this: it comprises upper and lower cover plate and silicon chip intermediate structure layer, it is characterized in that: said upper cover plate is siliceous plate; Silicon chip intermediate structure layer is, the anchor point of take is outwards annular quality frame, annular external electrode He Mao district successively as the center of circle, anchor district is the plane framework shape of square-outside and round-inside, wherein anchor district and anchor point and upper and lower cover plate bonding, four outer springs (forming outer spring frame) are cross and arrange, the two ends of each outer spring are separately fixed between anchor district and annular external electrode, and four inner springs (forming inner spring frame) are cross to be arranged, the two ends of each inner spring are separately fixed on annular quality frame and anchor point.

Like this, annular quality frame and annular external electrode are arranged on respectively on inside and outside spring(-supported) mount, and annular quality frame and annular external electrode are suspended between upper and lower cover plate, all become movable electrode.In switch is subject to x-y plane during the inertial acceleration of a direction, annular quality frame is towards this direction motion, when outside inertial acceleration reaches threshold value, under the acting in conjunction of inside and outside spring(-supported) mount, there is flexible contact in two movable electrodes (annular quality frame and annular external electrode), then move together, extended the time of contact of two electrodes.Also, because two movable electrodes are annular, guaranteed that in x-y plane, two movable electrodes can capture inertial acceleration in either direction, and the threshold value of either direction acceleration is consistent.

Compared with prior art, good effect of the present invention is: the inertial acceleration that can catch either direction in x-y plane; Next captures after threshold acceleration, has greatly extended two electrode contact times, makes switch performance more reliable, has significantly improved anti-interference and the reliability of switch.

Accompanying drawing explanation

Fig. 1 is structural representation of the present invention.

Fig. 2 is the A-A profile (omitting upper cover plate) of Fig. 1.

Embodiment

Referring to Fig. 1, it comprises upper cover plate 6, lower cover 8 and silicon chip intermediate structure layer, and said upper cover plate is siliceous plate; Referring to Fig. 2, silicon chip intermediate structure layer is, the anchor point 3 of take is outwards annular quality frame 1, annular external electrode 4 He Mao districts 7 successively as the center of circle, anchor district is the plane framework shape of square-outside and round-inside, wherein anchor district and anchor point and upper and lower cover plate bonding, four outer spring 5(formation outer spring framves) being cross arranges, the two ends of each outer spring are separately fixed between anchor district and annular external electrode, four inner spring 2(form inner spring frame) be cross layout, the two ends of each inner spring are separately fixed on annular quality frame and anchor point.

Manufacturing technique of the present invention is:

A) on intermediate structure layer silicon chip, thermal oxidation generates 5000 silicon dioxide layer, by M2 version (silicon chip back side ICP version), does mask, and photolithographic structures layer silicon chip, as ICP masking layer; The erosion of structure sheaf silicon chip back side ICP light engraving, etching depth 5um, the cleaning of removing photoresist, treats electrostatic bonding;

B) by M1 version (metal electrode version), make mask lithography sheet glass, corrosion Prex7740 glass 1800; Sputtered with Ti (400)-Pt (400)-Au (1200), utilizes photoresist lift off to make metal electrode, the cleaning of removing photoresist;

C) silicon slice pattern and glass electrode pattern alignment electrostatic bonding; Wafer thinning is polished to 60um;

D) by M3 version (front side of silicon wafer ICP version), make mask lithography, ICP releasing structure;

E) silicon dioxide layer of thermal oxidation generation 2um on cover plate silicon chip, does mask by M4 version (cover plate back side etched plate), and photoetching cover plate front side of silicon wafer, as KOH corrosion masking layer, KOH corrosion depth 200um; By M5 version (cover plate front etch and scribing version), do mask, photoetching cover plate silicon chip back side, as KOH corrosion masking layer, the two-sided corrosion depth 100um of KOH;

F) cover plate and structure sheaf BCB bonding; ICP etching PAD point.

Claims

1. a manufacture method for the micro electronmechanical universal inertia switch of growing time of contact, is characterized in that: said time of contact, long micro electronmechanical universal inertia switch comprised upper and lower cover plate and silicon chip intermediate structure layer, and upper cover plate is siliceous plate, silicon chip intermediate structure layer is, the anchor point of take is outwards annular quality frame successively as the center of circle, annular external electrode He Mao district, anchor district is the plane framework shape of square-outside and round-inside, wherein anchor district and anchor point and upper, lower cover bonding, four outer springs are cross and arrange, the two ends of each outer spring are separately fixed between anchor district and annular external electrode, four inner springs are cross and arrange, the two ends of each inner spring are separately fixed on annular quality frame and anchor point, like this, in annular quality frame and annular external electrode are arranged on respectively, on outer spring frame, annular quality frame and annular external electrode are suspended in, between lower cover, all become movable electrode,

The step of manufacturing long micro electronmechanical universal inertia switch time of contact is:

A) on intermediate structure layer silicon chip, thermal oxidation generates 5000 silicon dioxide layer, by M2 version, does mask, and photolithographic structures layer silicon chip, as ICP masking layer; The erosion of structure sheaf silicon chip back side ICP light engraving, etching depth 5um, the cleaning of removing photoresist, treats electrostatic bonding;

B) by M1 version, make mask lithography sheet glass, corrosion Prex7740 glass 1800; Sputtered with Ti thickness 400-Pt thickness 400-Au thickness 1200, utilizes photoresist lift off to make metal electrode, the cleaning of removing photoresist;

D) by M3 version, make mask lithography, ICP releasing structure;

E) silicon dioxide layer of thermal oxidation generation 2um on cover plate silicon chip, does mask by M4 version, and photoetching cover plate front side of silicon wafer, as KOH corrosion masking layer, KOH corrosion depth 200um; By M5 version, do mask, photoetching cover plate silicon chip back side, as KOH corrosion masking layer, the two-sided corrosion depth 100um of KOH;

F) cover plate and structure sheaf BCB bonding; ICP etching PAD point.