CN201075844Y

CN201075844Y - Holding-up drive type micro motor for reducing driving voltage

Info

Publication number: CN201075844Y
Application number: CNU2007201503446U
Authority: CN
Inventors: 洪银树; 黄义佑; 李彦其
Original assignee: JIANZHUN DYNAMO IND CO Ltd
Current assignee: JIANZHUN DYNAMO IND CO Ltd
Priority date: 2007-06-14
Filing date: 2007-06-14
Publication date: 2008-06-18
Anticipated expiration: 2017-06-14

Abstract

The utility model relates to a snatching driving micro-motor for reducing the driving voltage comprising a silicon substrate, an upper cover, an inner ring, a rib structure, at least more than one SDA slabs, at least more than one SDA supporting cantilever beams, an outer ring orbit and a lower electrode. The utility model is characterized in that the silicon substrate is a silicon substrate with an ultralow resistance value. The resistance value of the silicon substrate is below 0.004 Omega-cm. A first layer of polysilicon material is deposited on the silicon substrate with an ultralow resistance value. The upper cover is an immovable component fixed on the first layer of polysilicon material. A second layer of polysilicon material and a third layer of polysilicon material are deposited on the first layer of polysilicon material. The inner ring and the rib structure are respectively formed by the third layer of polysilicon material and the second layer of polysilicon material. The inner ring is connected with the rib structure, the SDA supporting cantilever beams are connected between the inner ring and the outer orbit. The SDA slabs are connected with the SDA supporting cantilever beams. The utility model can be used for assembling a micro-fan motor structure and can solve the defects of the traditional prior art.

Description

Can reduce the snatch drive-type micro motor of driving voltage

Technical field

The utility model relates to a kind of snatch drive-type (Scratch Drive Actuator; SDA) micro motor.

Background technology

In modern science, the development of miniaturization technology is of crucial importance with application, the fabrication techniques assembly that the global in recent years mini-fan (Micro Fan) that is developed is the utilization MEMS (micro electro mechanical system), and the size of mini-fan is about 2mm * 2mm.Mini-fan mainly is made up of gentle breeze fan flabellum that utilizes self-packaging technology (Self-assembly) to make and the SDA micro motor (Micro Motor) that utilizes micro-holding type actuator to form as rotor, the detailed making step of this assembly then adopts MEMSCAP, INC. (Man Si launches company) multi-user MEMS processing procedure (the Multi-User MEMS Processes that company developed; MUMPs).

Existing in the world in recent years many scientific papers are delivered and how to be used face type micro-processing technology (SurfaceMicromechaning Technology) to carry out the research and development relevant for SDA component application association area, wherein are the most representative and commercialization possibility of micro motor that drives rotor with SDA.Existing SDA micro motor physical characteristic has following four kinds with electrical the measurement:

1, Terunobu Akiyama people such as (Qiu Shanhui letters) successfully develop the SDA assembly and measure relation, input voltage peak value and each walking of the displacement of SDA actuating assembly and driving voltage and incoming frequency advance the relation of distance and the dull and stereotyped length of SDA and each walking advance apart between relation.

2, design SDA is connected on the flexible curved bar spare, measures the SDA power output with the deflection (Buckling) of flexural member, draws the relation of input voltage peak value and power output; Use the driver of SDA as Langlet (Lambert), and with the location of this platform application, and obtain of the influence of different SDA flat geometry the good rate of SDA by experimental result in the optical fiber coupling as the X/Y precisely locating platform.A plurality of SDA that turn one's coat are fixed on via special combination (Bonding) technology and form many group SDA on the glass baseplate, form the SDA conveyer belt.

3, Linderman people such as (Li Deman) forms a plurality of groups of objects that also utilize the connection of combination (Boading) technology to activate with 188 SDA, and then imports voltage with little chain.

4, with circular arrangement, form diameter is the rotation motor of 520 μ m to Bright (Bu Laite) with SDA, and silicon materials flabellum blade erected with binding element is fixed on the motor, is applied to promote microfluid.And SDA modular construction material is to make axle bush, conductive layer and cantilever beam structure with polycrystalline silicon material, the designed optimum size of Bright is dull and stereotyped long 78 μ m, wide 65 μ m of SDA, the height of axle bush and cantilever beam structure is 1.5 μ m, and length of cantilever be 30 μ m, wide be 4 μ m.

(30～150Vo-p) limit its commercialization uses for the high driving voltage of SDA micro motor but the weakest ring of all documents is exactly.

The shortcoming of another traditional SDA micro motor is that the lifetime is too short, and as shown in Figure 1, the junction of traditional SDA dull and stereotyped 4 and SDA support cantilever beam 5 is because the flexural rigidity deficiency is easy to cause fracture because reverse.

Summary of the invention

At the problems referred to above, main purpose of the present utility model is to provide a kind of snatch drive-type micro motor that reduces driving voltage, and it can significantly reduce driving voltage and can effectively promote the rotation life-span, prolongs the lifetime of SDA micro motor.

For achieving the above object, a kind of snatch drive-type micro motor that reduces driving voltage provided by the utility model includes: a silicon substrate; One loam cake; Ring in one; One framing system; At least more than one SDA flat board; At least more than one SDA support cantilever beam; One outer loop orbit; One bottom electrode; It is characterized in that: described silicon substrate is a ultralow resistance silicon substrate, and its resistance is 0.004 Ω-below the cm; Deposit the ground floor polycrystalline silicon material on the described ultralow resistance silicon substrate, described loam cake is to be the not movable member that is fixed in described ground floor polycrystalline silicon material, deposit second and third layer polycrystalline silicon material again on the described ground floor polycrystalline silicon material, ring is then formed by described the 3rd layer of polycrystalline silicon material and second layer polycrystalline silicon material respectively with framing system in described, and ring connects described framing system in described, described SDA support cantilever beam is connected between described interior ring and the described outer loop orbit, and described SDA flat board then is connected with described SDA support cantilever beam.

In the above-mentioned the technical solution of the utility model, the junction of described SDA support cantilever beam and described interior ring, outer loop orbit is provided with lead angle.

In the above-mentioned the technical solution of the utility model, described bottom electrode adopt the following ultralow resistance silicon substrate of 0.004 Ω-cm as the lower electrode material of SDA micro motor to reduce driving voltage.

Adopt technique scheme, the utility model adopts ultralow resistance first, and (0.001～0.004 Ω-cm) silicon substrate reduces SDA micro motor driving voltage, utilize yellow light lithography manufacture method that the SDA micro motor is produced on the ultralow resistance silicon substrate, the driving voltage of SDA micro motor significantly can be reduced, be reduced to 12～30Vo-p by the 30～150Vo-p in past.In addition, in order to promote the lifetime of SDA micro motor, the utility model has adopted new-type rib and lead angle structural design, and the lead angle structure of increase strengthens rotary torsion between cantilever beam one external slide rail road and SDA one cantilever beam, can effectively promote to rotate the life-span.And the design of novel lead angle of the present utility model and rib can effectively promote the SDA micro motor and rotate the life-span, reaches more than 75 hours and its maximum speed reaches 30rpm.Because the utility model can be widely used in multiple microminiaturized industry, no matter be to consider that from each side such as production cost, manufacture process and microminiaturizations the utility model all can solve the shortcoming of traditional known techniques.

Description of drawings

Fig. 1 is the section of structure of traditional SDA micro motor;

Fig. 2 is the section of structure of the utility model SDA micro motor;

Fig. 3 is a lead angle schematic diagram of the present utility model;

Fig. 4 A, Fig. 4 B are the utility model SDA micro motor fabrication steps schematic diagrames;

Fig. 5 A is the vertical view of the utility model SDA micro motor;

Fig. 5 B is the side structure cutaway view of the utility model SDA micro motor;

Fig. 6 is driving voltage and silicon substrate resistance graph of a relation;

Fig. 7 is the enforcement schematic diagram that the utility model SDA applies to mini-fan.

Embodiment

Now lifting following examples also is elaborated to structure of the present utility model, effect and characteristics in conjunction with the accompanying drawings.

SDA micro motor provided by the utility model, as shown in Figure 2, it comprises:

One loam cake, 8, one interior ring 6, one framing system 7, at least more than one SDA support cantilever beam 5, at least more than one the dull and stereotyped 4 and one outer loop orbit 14 of SDA.

Wherein, loam cake 8 is for being fixed in the not movable member of ground floor polycrystalline silicon material 1, in ring 6 and framing system 7 be the 3rd layer of polycrystalline silicon material 3 and being connected of second layer polycrystalline silicon material 2, in SDA support cantilever beam 5 is connected between ring 6 and the

outer loop orbit

14,4 of SDA flat boards are connected with SDA support cantilever beam 5.

As shown in Figure 1 and Figure 2, can compare the difference that the utility model and traditional SDA micro motor exist on agent structure:

In order to increase the torsion of SDA support cantilever beam 5, the utility model is to adopt the 3rd layer of polycrystalline silicon material 3 as the main structure layer, forms SDA flat board 4, SDA support cantilever beam 5, interior ring 6 and loam cake 8.Tradition SDA micro motor then is to utilize second layer polycrystalline silicon material 2 as the main structure layer.

The main function of framing system 7 of the present utility model is, utilize second layer polycrystalline silicon material 2 as trip and be connected on the 3rd layer of polycrystalline silicon material 3, ring 6 and framing system 7 are the 3rd layer of polycrystalline silicon material 3 and being connected of second layer polycrystalline silicon material 2 wherein, can improve traditional SDA micro motor utilizes second layer polycrystalline silicon material 2 as framing system 7 merely, and the SDA micro motor is because many one deck polysilicon structures, interior ring 6 closely can be blocked with loam cake 8, so just can improve the structure tightness of rotating the life-span and increasing assembly.

As shown in Figure 3, be the novel designs lead angle 9 that the utility model adopts, the main effect of lead angle 9 is to increase the structural strength of SDA support cantilever beam 5, improves the good rate of SDA micro motor, prevents to cause micro motor to lose efficacy because of long-time torsional fracture.

Utilize sweep electron microscope can clearly observe the lead angle that the utility model is provided with in the SDA micro motor.Adopt the design of lead angle 9, the utility model the experiment proved that, the continuous operation time of SDA micro motor can be promoted to significantly to surpass 75 hours and rotating speed reaches more than the 30rpm.

Shown in Fig. 4 A, Fig. 4 B, the making step of SDA micro motor of the present utility model is as follows for another example:

(1) use LPCVD (low-pressure chemical vapor deposition) system on ultralow resistance silicon substrate 10, to deposit low stress (250MPa) silicon nitride film (Si ₃N ₄) as insulating barrier 11, and utilize the first road photolithography and dry-etching technology to define the exposed region of ultralow resistance silicon substrate 10, as bottom electrode contact window 12.The utility model adopts the lower electrode material of the ultralow resistance silicon substrate 10 of 0.001～0.004 Ω-cm as the SDA micro motor, to reach effective reduction driving voltage.

(2) on insulating barrier 11, use the LPCVD system to deposit ground floor low stress (200MPa) doped polycrystalline silicon film 13 of 1.5 μ m, and chip inserted horizontal boiler tube to carry out phosphorous diffusion and high annealing processing procedure, utilize the outer loop orbit (trail) 14 of the second road photolithography and reaction equation coupled plasma (ICP) dry-etching technology definition SDA micro motor at last.

(3) use ground floor low stress phosphorosilicate glass material film 16 that PECVD (plasma enhanced chemical vapor deposition) system deposits 2 μ m as ground floor low stress (300MPa) sacrifice layer, and utilize the 3rd road photolithography and dry-etching technology to define miniature prominent some contact window 17 and axle bush contact window 18.

(4) use the LPCVD system to deposit the second layer low stress doped polycrystalline silicon film 19 of 2 μ m, and chip inserted horizontal boiler tube to carry out phosphorous diffusion and high annealing processing procedure, utilize the 4th road photolithography and dry-etching technology definition framing system (rib) 7 at last.

(5) use second layer low stress phosphorosilicate glass material film 21 that the PECVD system deposits 1.5 μ m as second layer low stress sacrifice layer, and utilize the 5th road photolithography and dry-etching technology to define miniature prominent some contact window 22 and axle bush contact window 24.

(6) then carry out the 6th road optical photomicrography resolution, and utilize the figure of dry-etching technology etching anchoring part contact window 25 with definition loam cake (cover).

(7) use the LPCVD system to deposit the 3rd layer of low stress doped polycrystalline silicon film 26 of 2 μ m as the main structure layer, and chip inserted horizontal boiler tube to carry out phosphorous diffusion and high annealing processing procedure, utilize the main structure zone of the 7th road photolithography and dry-etching technology definition SDA micro motor, wherein comprise at least one miniature prominent point 27, SDA support cantilever beam 5, interior ring 6, loam cake 8, SDA dull and stereotyped 4 and axle bush 31.

(8) utilize E-beam (electron beam evaporation plating machine) the vapor deposition 200nm/250nm Cr/Au of system metallic film, and utilize the 8th road photolithography and Wet-type etching technology to define top electrode 34 and bottom electrode 35 patterns.

(9) the working concentration dilution is 49% HF (hydrofluoric acid) etching ground floor and second layer low stress phosphorosilicate

glass material film

16,21, to discharge the main structure layer of SDA micro motor.

By the SDA micro motor that adopts above-mentioned making step to make, shown in Fig. 5 A, Fig. 5 B, can improve the shortcoming in traditional SDA micro motor high driving voltage and low life-span, and the utility model utilizes ultralow resistance silicon substrate 10 first, and (0.001 Ω-cm) driving voltage with the SDA micro motor is reduced to 12～30Vo-p by 30～150Vo-p.

According to the dividing potential drop theorem, the driving voltage of SDA micro motor is relevant with the resistance of silicon substrate, as shown in Figure 6, for comparing two SDA actuators of on the silicon substrate of different resistances, making respectively in the same process mode (single SDA flat board), SDA on ultralow resistance substrate is as long as 4～7Vo-p driving voltage is promptly movable, the SDA micro motor driving voltage of eight SDA assemblies of serial connection is 12～30Vo-p, and is much lower more than the driving voltage of the SDA assembly that utilizes the ordinary silicon substrate.

As shown in Figure 7, application for a kind of new-type SDA micro motor 40, the utility model is called mini-fan, mini-fan combines SDA micro motor 40 and eight minitype flabellum structures 41 of utilizing self-packaging technology exploitation, and the actuating force that the pi elastic contact 42 of connection SDA micro motor 40 and minitype flabellum structure 41 lifts blade structure then is to utilize the pi material process surface tension that high-temperature baking produced itself.

The SDA micro motor can be used in the technology of multiple microminiaturized industry, especially for the making of mini-fan, can break through the technology hedge of present mini-fan, reaches the target of low driving voltage and high life cycle, the real initiative that belongs in the middle of like product.

The above only is a preferable enforcement kenel of the present utility model, and the equivalent structure that all application the utility model specifications, claims or accompanying drawing are done changes, and all should be included in the scope of patent protection of the present utility model.

Claims

1. snatch drive-type micro motor that can reduce driving voltage includes:

One silicon substrate;

One loam cake;

Ring in one;

One framing system;

At least more than one SDA flat board;

At least more than one SDA support cantilever beam;

One outer loop orbit;

One bottom electrode;

It is characterized in that: described silicon substrate is a ultralow resistance silicon substrate, and its resistance is 0.004 Ω-below the cm; Deposit the ground floor polycrystalline silicon material on the described ultralow resistance silicon substrate, described loam cake is to be the not movable member that is fixed in described ground floor polycrystalline silicon material, deposit second and third layer polycrystalline silicon material again on the described ground floor polycrystalline silicon material, ring is then formed by described the 3rd layer of polycrystalline silicon material and second layer polycrystalline silicon material respectively with framing system in described, and ring connects described framing system in described, described SDA support cantilever beam is connected between described interior ring and the described outer loop orbit, and described SDA flat board then is connected with described SDA support cantilever beam.

2. can reduce the snatch drive-type micro motor of driving voltage according to claim 1, it is characterized in that: the junction of described SDA support cantilever beam and described interior ring, outer loop orbit is provided with lead angle.

3. can reduce the snatch drive-type micro motor of driving voltage according to claim 1, it is characterized in that: described bottom electrode adopt the following ultralow resistance silicon substrate of 0.004 Ω-cm as the lower electrode material of SDA micro motor to reduce driving voltage.