CN206735793U - Microheater - Google Patents

Abstract

The utility model discloses a kind of microheater, including：Substrate, support membrane, heating member and encapsulating shell.Substrate has the first surface and second surface being oppositely arranged along its thickness direction, substrate is provided with runs through its heat-insulated through hole in thickness direction, and heat-insulated through hole and extraneous ventilation device are communicated with substrate, support membrane is located on the first surface of substrate and covers the first end of heat-insulated through hole, heating member is located on the surface of remote heat-insulated through hole of support membrane, and encapsulating shell is located on the second surface of substrate and covers the second end of heat-insulated through hole.According to microheater of the present utility model, heat-insulated through hole and extraneous ventilation device are connected by being set on substrate, thus when microheater works, the chamber limited by heat-insulated through hole, support membrane and encapsulating shell is in communication with the outside, and prevents from causing the flimsy problem of device due to existing pressure differential inside and outside chamber.

Description

Microheater

Technical field

Micro-electromechanical system field is the utility model is related to, more particularly, to a kind of microheater.

Background technology

In correlation technique, the structure of micro-hotplate mainly has closing membrane structure and cantilever beam structure, cantilever beam structure Power consumption than closing membrane structure it is low in energy consumption, and cantilever beam structure due to composite membrane thermal stress release problem device will be caused to exist Risen and fallen on horizontal plane, and with the rise of device reaction temperature, for composite membrane by expanded by heating, these can all increase cantilever beam knot Structure thermal stress localized clusters.Close membrane mechanical performance is more preferable, and it is poor but compatible good with CMOS technology to hang film mechanical performance A bit.Because closed film mechanical strength is more preferable, and be advantageous to the coating of follow-up sensitive material and proposing for subsequent sensor life-span Height, most sensors use this design.

However, the micro-hotplate of closing membrane structure, in the long-term course of work, its internal device easily damages Bad problem, so as to influence the reliability of the practical effect of sensor and work.

Utility model content

The application is made based on discovery of the utility model people to following facts and problem and understanding：Utility model people is led to Cross research to find, close the micro-hotplate of membrane structure in the long-term course of work, its internal device is damaged master If as caused by being broken fatigue of materials.By the further research and exploration of utility model people, the fatigue for causing device is found The reason for fracture, is：Closing the gas pressure change in the chamber of the micro- heating of face type of membrane structure causes its support membrane to remove by certainly Body thermal stress influence it is outer, also by periodicity/chronicity pressure differential caused by draught head so that support membrane periodicity/ Fatigue fracture easily occurs in the presence of chronicity pressure differential.

The utility model is intended at least solve one of technical problem present in prior art.Therefore, the utility model carries Go out a kind of microheater, the microheater is simple in construction, service life is long, reliability is high.

According to the microheater of the utility model embodiment, including：Substrate, the substrate have along its thickness direction phase To the first surface and second surface of setting, the substrate is provided with runs through its heat-insulated through hole, and the lining in thickness direction The heat-insulated through hole and extraneous ventilation device are communicated with bottom；Support membrane, the support membrane are located at the described of the substrate On first surface and the capping heat-insulated through hole first end；Heating member, the heating member are located at the remote institute of the support membrane On the surface for stating heat-insulated through hole；Encapsulating shell, the encapsulating shell be located on the second surface of the substrate and cover it is described every Second end of heat through-hole.

According to the microheater of the utility model embodiment, heat-insulated through hole and the external world are connected by being set on substrate Ventilation device, thus when microheater works, connected by the chamber that heat-insulated through hole, support membrane and encapsulating shell limit with extraneous It is logical, prevent from causing the flimsy problem of device due to existing pressure differential inside and outside chamber.

According to some alternative embodiments of the present utility model, the second surface of the substrate is provided with groove, described The ventilation device is limited between groove and the encapsulating shell.

Alternatively, the groove is multiple and being provided at circumferentially spaced along the heat-insulated through hole.

Alternatively, the cross section of the groove is curved or U-shaped.

According to some alternative embodiments of the present utility model, the end shape positioned at the first surface of the heat-insulated through hole As circle.

Further, the cross-sectional area of the heat-insulated through hole is by the first surface to the direction of the second surface Upper increase.

According to some alternative embodiments of the present utility model, the heating member is resistive heater, the resistive heater Curvature varying in their extension direction is continuous.

Alternatively, projection of the resistive heater on the support membrane be rounded, oval, involute shape or summit Locate the polygon of rounding.

Alternatively, the resistive heater includes parallel to each other and spaced multiple straight sections and connection is two neighboring The curved segment of the straight section, the curved segment and the junction of the straight section seamlessly transit.

Additional aspect and advantage of the present utility model will be set forth in part in the description, partly by from following description In become obvious, or by it is of the present utility model practice recognize.

Brief description of the drawings

Of the present utility model above-mentioned and/or additional aspect and advantage will in the description from combination accompanying drawings below to embodiment Become obvious and be readily appreciated that, wherein：

Fig. 1 is the part isometric structure chart according to the microheater of the utility model embodiment；

Fig. 2 is the part isometric structure chart according to another angle of the microheater of the utility model embodiment.

Reference：

Substrate 1, first surface 11, second surface 12, heat-insulated through hole 13, first paragraph 131, second segment 132, ventilation device 14,

Support membrane 2,

Heating member 3, straight section 31, curved segment 32,

Electrode 4.

Embodiment

Embodiment of the present utility model is described below in detail, the example of the embodiment is shown in the drawings, wherein from beginning Same or similar element is represented to same or similar label eventually or there is the element of same or like function.Below by ginseng The embodiment for examining accompanying drawing description is exemplary, is only used for explaining the utility model, and it is not intended that to of the present utility model Limitation.

In description of the present utility model, it is to be understood that term " " center ", " thickness ", " on ", " under ", " preceding ", The instruction such as " rear ", "left", "right", " vertical ", " level ", " top ", " bottom " " interior ", " outer ", " axial direction ", " radial direction ", " circumference " Orientation or position relationship are based on orientation shown in the drawings or position relationship, are for only for ease of description the utility model and simplification Description, rather than the device or element of instruction or hint meaning must have specific orientation, with specific azimuth configuration and behaviour Make, therefore it is not intended that to limitation of the present utility model.In addition, define " first ", the feature of " second " can be expressed or Person implicitly includes one or more this feature.In description of the present utility model, unless otherwise indicated, " multiples' " contains Justice is two or more.

, it is necessary to which explanation, unless otherwise clearly defined and limited, term " are pacified in description of the present utility model Dress ", " connected ", " connection " should be interpreted broadly, for example, it may be fixedly connected or be detachably connected, or integratedly Connection；Can be mechanical connection or electrical connection；Can be joined directly together, can also be indirectly connected by intermediary, It can be the connection of two element internals.For the ordinary skill in the art, above-mentioned art can be understood with concrete condition Concrete meaning of the language in the utility model.

Microheater below with reference to Fig. 1 and Fig. 2 descriptions according to the utility model embodiment.

As depicted in figs. 1 and 2, according to the microheater of the utility model embodiment, including：Substrate 1, support membrane 2, add Warmware 3 and encapsulating shell (not shown).For example, above-mentioned microheater can be micro-hotplate, above-mentioned microheater It can apply to sensor field.

Specifically, substrate 1 has the first surface 11 and second surface 12 being oppositely arranged along its thickness direction, in substrate 1 when placing in the horizontal direction, first surface 11 and the upper and lower surface that second surface 12 is substrate 1.Substrate 1 is provided with Thickness direction runs through its heat-insulated through hole 13, and heat-insulated through hole 13 and extraneous ventilation device 14 are communicated with substrate 1.It is optional Ground, substrate 1 can be silicon substrate.

Support membrane 2 is located on the first surface 11 of substrate 1 and covers the first end of heat-insulated through hole 13, the middle part of support membrane 2 The first end of heat-insulated through hole 13 is covered, its neighbouring periphery edge of support membrane 2 is partially supported upon on substrate 1 and is connected with substrate 1. Support membrane 2 can be silicon oxide film, silicon nitride film or silica/silicon nitride composite membrane.

Heating member 3 is located on the surface of remote heat-insulated through hole 13 of support membrane 2, is supported heating member 3 by support membrane 2 and is incited somebody to action Heating member 3 is spaced with heat-insulated through hole 13.Alternatively, heating member 3 can be thread, sheet etc..It is additionally provided with and heats on substrate 1 The connected electrode 4 of part 3, electrode 4 can be set with the periphery edge of adjacent substrate 1.For example, when substrate 1 is square, electrode 4 can be with It is located at four corners of substrate 1.

Encapsulating shell is located on the second surface 12 of substrate 1 and covers the second end of heat-insulated through hole 13, passes through encapsulating shell, support Film 2 covers the second end and the first end of heat-insulated through hole 13 respectively so that common between encapsulating shell, support membrane 2 and heat-insulated through hole 13 Limit chamber.

It is understood that during microheater works, heating member 3, which works, can produce heat, and support membrane 2 Heating member 3 and heat-insulated through hole 13 are separated, now different pressure, two tables of support membrane 2 are born in the two of support membrane 2 surface A surface in face is towards heating member 3 and another surface towards above-mentioned chamber so that support membrane 2 is removed by itself thermal stress shadow Ring outer, the pressure differential as caused by heat also suffered from.

, can be by the chamber and the external world by the ventilation device 14 by being provided with above-mentioned ventilation device 14 on substrate 1 Connection, thus when microheater works, gas pressure and the gas pressure of its outside in above-mentioned chamber can be reduced Pressure differential so that gas pressure and the gas pressure of its outside in above-mentioned chamber reach unanimity, so as to reduce support membrane 2 Suffered pressure differential so that the pressure at both sides of support membrane 2 reaches unanimity, so as to prevent support membrane 2 because by periodically/length Fatigue damage problem caused by the pressure differential of phase property, extend the service life of microheater, improve microheater work Reliability.

According to the microheater of the utility model embodiment, by setting the heat-insulated through hole 13 of connection and outer on substrate 1 The ventilation device 14 on boundary, thus when microheater works, the chamber that is limited by heat-insulated through hole 13, support membrane 2 and encapsulating shell It is in communication with the outside, prevents from causing the flimsy problem of device due to existing pressure differential inside and outside chamber.

According to some alternative embodiments of the present utility model, reference picture 2, the second surface 12 of substrate 1 is provided with groove, should Groove can radially extend and the periphery wall of the inwall through heat-insulated through hole 13 and substrate 1, is limited between groove and encapsulating shell Go out ventilation device 14.Thus, by setting groove on the second surface 12 of substrate 1, the processing of ventilation device 14 can be facilitated Shaping, and make it that ventilation device 14 is simple.

Alternatively, reference picture 2, groove can be multiple and being provided at circumferentially spaced along heat-insulated through hole 13.Thus, it is possible to make Gas in above-mentioned chamber and its outside gas can rapidly and uniformly circulate so that gas pressure in chamber with outside it The gas pressure in portion quickly reaches unanimity, while can be more uniformly distributed the gas pressure of the various pieces in chamber.For example, Above-mentioned multiple grooves can radially be set, it is possible thereby to shorten the flow path of gas, while can increase the stream of gas Dynamic area, preferably the pressure at both sides of support membrane 2 can be reached unanimity, more significantly reduce the pressure suffered by support membrane 2 Power is poor.

Alternatively, the cross section of above-mentioned groove can be with curved or U-shaped.So that the structure of groove is simple, is easy to add Work is molded, while is caused the internal face of groove smooth and avoided the generation of stress, and further increasing microheater can By property.

According to some alternative embodiments of the present utility model, referring to Figures 1 and 2, heat-insulated through hole 13 is located at first surface 11 end is formed as circular so that the part of the heat-insulated through hole 13 of capping of support membrane 2 is also circle, i.e., is in support membrane 2 Hanging part is circle, it is possible thereby to make in support membrane 2 in its edge of hanging part to be smooth continuous and avoid The appearance of salient angle, so as to prevent the problem of stress concentration of support membrane 2, further improve life-span of support membrane 2 and miniature The reliability of heater work.Alternatively, support membrane 2 is overall can be with rounded or square.

Further, the cross-sectional area of heat-insulated through hole 13 is in (the ginseng by first surface 11 to the direction of second surface 12 According on the direction from top to bottom in Fig. 2) increase.Thus, it is possible to the overall structure stability and intensity of microheater are improved, The chip density of microheater can be improved simultaneously.

For example, heat-insulated through hole 13 can be formed as truncated cone-shaped.

In another example reference picture 2, heat-insulated through hole 13 can include internal diameter different first paragraph 131 and second segment 132, above-mentioned First paragraph 131 and second segment 132 are all formed as cylinder, wherein first paragraph 131 adjacent to heat-insulated through hole 13 first surface 11, Two section of 132 second surface 12 adjacent to heat-insulated through hole 13, the internal diameter of first paragraph 131 are less than the internal diameter of second segment 132.

According to some alternative embodiments of the present utility model, reference picture 1, heating member 3 can be resistive heater, heating electricity It is continuous to hinder the Curvature varying of silk in their extension direction.As a result, it is flat between the various pieces of resistive heater Slip transition, can prevent occurring the problem of structural stress concentration on heating member 3, further improve microheater can By property.

For example, projection of the resistive heater on support membrane 2 can be fallen with rounded, oval, involute shape or apex The polygon of fillet.

In another example reference picture 1, resistive heater can include parallel to each other and spaced multiple straight sections 31 and connect The curved segment 32 of two neighboring straight section 31 is connect, curved segment 32 and the junction of straight section 31 seamlessly transit.Thus, it is possible to make resistive heater It is evenly distributed on support membrane 2 so that microheater can obtain the samming region of larger area and high quality at work.

Processing method referring to Fig. 1 and Fig. 2 descriptions according to the microheater of the utility model embodiment.

According to the processing method of the microheater of the utility model embodiment, may include steps of：

S10, substrate 1 first surface 11 deposition form support membrane 2.Chemical vapour deposition technique can be utilized in substrate 1 deposition of first surface 11 forms above-mentioned support membrane 2, and the support membrane 2 can be structure of composite membrane.It is for instance possible to use low pressure Chemical vapour deposition technique or plasma enhanced chemical vapor deposition technology deposit on the first surface 11 of substrate 1 forms oxygen SiClx/silicon nitride composite membrane.Wherein, can be to the first surface 11 and second of substrate 1 on substrate 1 before depositing support film 2 Surface 12 is polished, it is possible thereby to strengthen the bonding strength and reliability between support membrane 2 and substrate 1.

S20, heating member 3 is laid on support membrane 2, can be deposited using sputtering technology on support membrane 2 and form heating member 3, such as the method that magnetron sputtering can be used.According to design requirement on support membrane 2 sputtering sedimentation slabbing or it is thread plus Warmware 3, the graphics shape of heating member 3 can be circle, ellipse, the polygon or snakelike of involute shape, apex rounding.

S30, from the second surface 12 of substrate 1 along its thickness direction (direction from bottom to top in reference picture 2) etch serve as a contrast Bottom 1 is to form heat-insulated through hole 13, and etched substrate 1 is to form groove on the second surface 12 of substrate 1.Heat-insulated through hole 13 and groove Etching can carry out simultaneously, can also successively carry out (for example, can first etch heat-insulated through hole 13, then etched recesses).Certainly, Heat-insulated through hole 13 and groove etch simultaneously can improve processing efficiency.

S40, use bonding agent that encapsulating shell is connected with substrate 1 to encapsulate the internal components of microheater.In encapsulation, Bonding agent is smeared on the package, then encapsulating shell is be bonded with the second surface 12 of substrate 1.Bonding agent is smeared on the package When so that the bonding agent thickness of the bonding region on encapsulating shell can it is homogeneous and less than groove depth, with prevent encapsulating shell with Substrate 1 be bonded when glued dose of groove fill up and so that the ventilation device 14 of microheater is plugged.

According to the processing method of the microheater of the utility model embodiment, process is simple, easy to operate and shaping Quality is high.

According to some alternative embodiments of the present utility model, in above-mentioned S30 steps, heat-insulated through hole 13 and groove are etched Step is as follows：

First use dry etching technology heat-insulated to be formed along its thickness direction etched substrate 1 by the second surface 12 of substrate 1 The Part I of through hole 13, use above-mentioned dry etching technology on the second surface 12 of substrate 1 etched substrate 1 to form groove Part I.

Continue the thickness direction along substrate 1 on the basis of the Part I of heat-insulated through hole 13 using wet etching technique again Etched substrate 1 continues to carve to form heat-insulated through hole 13, using above-mentioned wet etching technique on the basis of the Part I of groove Substrate 1 is lost to form groove.

Thus, the technology being combined by dry etching technology with wet etching technique, microheater can be reduced Processing cost, and Forming Quality can be ensured.Moreover, first carved again using wet method using dry etching when etching heat-insulated through hole 13 Erosion, damage caused by dry etching can be avoided possible to support membrane 2；Dry etching and wet etching are used in etched recesses The technology being combined, the depth of groove can be improved, avoid the above-mentioned chamber formation closed chamber of microheater after encapsulation.

Alternatively, above-mentioned dry etching technology can be deep reaction ion etching.

Alternatively, the corrosive agent of above-mentioned wet etching technique can be Triton X-100 and tetramethyl hydroxide The mixed solution of ammonium.For example, when substrate 1 is silicon substrate, the corrosive agent of wet etching technique uses above-mentioned mixed solution, can To eliminate acute angle stress concentration structure caused by anisotropic silicon, and be advantageous to eliminate and corruption caused by boss is formed on groove Erosion problem.

In the description of this specification, reference term " one embodiment ", " some embodiments ", " illustrative examples ", The description of " example ", " specific example " or " some examples " etc. means to combine specific features, the knot that the embodiment or example describe Structure, material or feature are contained at least one embodiment or example of the present utility model.In this manual, to above-mentioned art The schematic representation of language is not necessarily referring to identical embodiment or example.Moreover, description specific features, structure, material or Person's feature can combine in an appropriate manner in any one or more embodiments or example.

While there has been shown and described that embodiment of the present utility model, it will be understood by those skilled in the art that： These embodiments can be carried out with a variety of changes, modification in the case where not departing from principle and objective of the present utility model, replaced And modification, the scope of the utility model are limited by claim and its equivalent.

Claims (9)

1. A kind of 1. microheater, it is characterised in that including：

   Substrate, the substrate have the first surface and second surface being oppositely arranged along its thickness direction, and the substrate is provided with Run through its heat-insulated through hole in thickness direction, and the heat-insulated through hole and extraneous ventilation device are communicated with the substrate；

   Support membrane, the support membrane are located on the first surface of the substrate and cover the first end of the heat-insulated through hole；

   Heating member, the heating member are located on the surface of the remote heat-insulated through hole of the support membrane；

   Encapsulating shell, the encapsulating shell are located on the second surface of the substrate and cover the second end of the heat-insulated through hole.
2. 2. microheater according to claim 1, it is characterised in that the second surface of the substrate is provided with recessed Groove, the ventilation device is limited between the groove and the encapsulating shell.
3. 3. microheater according to claim 2, it is characterised in that the groove is multiple and along the heat-insulated through hole Be provided at circumferentially spaced.
4. 4. microheater according to claim 2, it is characterised in that the cross section of the groove is curved or U-shaped.
5. 5. according to the microheater any one of claim 1-4, it is characterised in that the heat-insulated through hole is located at institute The end for stating first surface is formed as circular.
6. 6. microheater according to claim 5, it is characterised in that the cross-sectional area of the heat-insulated through hole is by institute The side for stating first surface to the second surface is increased up.
7. 7. according to the microheater any one of claim 1-4, it is characterised in that the heating member is adding thermal resistance Silk, the Curvature varying of the resistive heater in their extension direction is continuous.
8. 8. microheater according to claim 7, it is characterised in that the resistive heater is on the support membrane Project the polygon of rounded, oval, involute shape or apex rounding.
9. 9. microheater according to claim 7, it is characterised in that the resistive heater include it is parallel to each other and Every multiple straight sections of setting and the curved segment of the two neighboring straight section of connection, the curved segment and the junction of the straight section are smooth Transition.