CN1536335A - Microcantilever sensor and its making method - Google Patents

Abstract

The invention relates to a micro cantilever beam sensor and making method, including a chip, and its character: there is at least a group of sensor cells set on the chip, where the sensor cell is composed of the completely same four force-sensitive resistors composing a Wheatstone bridge and two cantilever beams, two of these resistors are on the substrate of the chip, the other two are on the two cantilever beams, respectively, one cantilever beam acts on a measuring cantilever beam and the other one acts on a reference cantilever beam, and each cantilever beam each has a window to make it set on the chip in a U-shape and the measuring cantilever beam is set with a sensitive layer on the surface. It can design and prepare in a liquid-flow microtank by the front etching and silicon-glass bonding techniques, to directly detect liquid biomolecule. Whether applied to gas sensor or biosensor, it will play an important role in reducing device size, enhancing device sensitivity and realizing sensor multi-functionality. It has wide prospects for the fields of environment monitoring, clinic diagnosis and therapy, new drug development, food safety, industrial processing control, military and so on.

Description

A kind of micro-cantilever beam sensor and preparation method thereof

Technical field

The present invention relates to a kind of sensor and preparation method thereof, particularly micro-cantilever beam sensor that takes the shape of the letter U about a kind of semi-girder and preparation method thereof.

Background technology

In 20 years of past, one of obvious improvement of microelectric technique is the development of new measuring technology.Scanning probe microscopy is one of well-known detection technique, and wherein scanning tunnel microscope and scanning force microscopy are the most representative two kinds of highly sensitive detecting instruments.The principle of work of scanning force microscopy be with probe stationary one to the highstrung micro-cantilever of faint power on, and make it and the testing sample surface atom between have the interaction of power, the power that acts between probe and the sample makes semi-girder generation deformation, and go on record, because micro-cantilever is very responsive to the variation of faint power, therefore can high-resolution imaging material surface pattern, the research surface nature.

The slight curves of semi-girder is come record by optics or electrical method usually.Optical detecting method can obtain little vertical resolution to 0.01 , though it has higher sensitivity, the huge optical measuring system and the close adjustment of laser have limited it and have used widely: as under ultrahigh vacuum, low temperature, the liquid condition and in the measurement of array semi-girder.The method of breaking away from this problem is integrated capacitance, piezoelectricity, the force sensing element electrical detection method in semi-girder, because the electrical detection method is easier to operation than optical means, is easy to turn to practicability.In the electrical detection method, pressure resistance type reading method on the throne is easier to realize than other detection technique.

In recent years, highly sensitive micro-cantilever technology is applied to the research focus that biology, chemical sensor become sensor field.This class sensor can be surveyed the existence of micro-biochemical molecular under gaseous state or liquid condition, as airborne organic gas, harmful gas, aromatic, and the DNA of liquid, protein etc.Although the research work of semi-girder biochemical sensor has obtained some achievements, also have with a certain distance from widespread use, particularly in liquid Study on Biosensor field.Problems such as simultaneously, it is complicated also to exist manufacture craft on the manufacture craft of beam type microsensor, and yield rate is lower.

Summary of the invention

The objective of the invention is to provide on the basis of existing technology a kind of measurement sensitivity higher, simpler micro-cantilever beam sensor of manufacture craft and preparation method thereof.

For achieving the above object, the present invention takes following technical scheme: a kind of micro-cantilever beam sensor, it comprises a chip, it is characterized in that: described chip is provided with at least one group of sensing unit, described sensing unit is made up of four identical force sensing resistances and two semi-girders of forming Wheatstone bridge, wherein two described resistance are positioned on the substrate of described chip, two other lays respectively on described two semi-girders, one of them is as measuring semi-girder, another is as the reference semi-girder, have a window on each described semi-girder, described semi-girder is taken the shape of the letter U be arranged on the described chip, described measurement semi-girder surface is provided with sensitive layer.

Described sensing unit is a plurality of.

The semi-girder of described sensing unit is arranged on a side of described chip.

Described chip is provided with a microflute, and the semi-girder of described sensing unit is arranged on described microflute both sides.

Can be provided with a microflute by described chip, described sensing unit is set in described microflute both sides.

Described sensitive layer is the high molecule sensitivity material.

Described sensitive layer is a bioactive molecule.

Described length of cantilever 50～500 μ m, wide 10～100 μ m, thick 100～5000nm, U-shaped brachium 20～200 μ m of described window both sides, wide 5～50 μ m.

Described force sensing resistance is of a size of long 20～200 μ m, wide 5～50 μ m.

The method for making of above-mentioned micro-cantilever beam sensor is characterized in that it may further comprise the steps:

1, adopt soi wafer, and the attenuate device layer is as chip substrate with oxide layer, single-crystal silicon device layer; Perhaps adopt single-sided polishing p type silicon chip, carry out after routine cleans, at silicon chip surface plasma enhanced CVD silicon nitride, then at silicon nitride surface low pressure chemical vapor deposition polysilicon as chip substrate;

2, monocrystalline silicon or the injection of polysilicon front boron ion are mixed;

3, with mask plate the chip through step 2 is carried out the photoetching first time,, form force sensing resistance through etching;

4, the chip surface through step 3 is passed through the plasma enhanced CVD silicon nitride, then in AN;

5, with mask plate the chip through step 4 is carried out the photoetching second time,, form the arm and the window of force sensing resistance contact hole and U-shaped semi-girder through etching;

6, the chip surface through step 5 is passed through electron beam, sputter chromium/golden thermometal film;

7, with mask plate the chip through step 6 is carried out photoetching for the third time,, form the metal wire that connects each force sensing resistance through corrosion;

8, on entire chip, carry out the scribing of single-sensor;

9, with the chip of potassium hydroxide corrosion, discharge semi-girder through step 8;

10, metal wire in the force sensing resistance contact hole on the chip and chip substrate are carried out alloy treatment;

11, be single-sensor with the entire chip sliver;

12, a semi-girder surface in per two semi-girders is provided with sensitive layer.

Wherein step 5 forms the microflute on the chip in arm that forms force sensing resistance contact hole and U-shaped semi-girder and window.

Step 1 wherein, the oxidated layer thickness of soi wafer is 200～800nm, device layer thickness is 100～500nm.

Step 1 wherein, when silicon chip surface carried out the plasma enhanced CVD silicon nitride, the thickness of silicon nitride was 100～1000nm.

Step 1 wherein, when the low pressure chemical vapor deposition polysilicon, the thickness of polysilicon is 100～500nm.

Step 2 is wherein injected when mixing monocrystalline silicon or polysilicon front boron ion, and the concentration of injecting the boron ion is 5 * 10 ¹³Cm ^-2～5 * 10 ¹⁵Cm ^-2, inject energy 30keV～80keV.

Step 4 wherein, during the plasma enhanced CVD silicon nitride, silicon nitride thickness is 100～1000nm, 900～1100 ℃ of annealing 20～30 minutes in nitrogen then.

The present invention is owing to take above technical scheme, it has the following advantages: 1, the present invention is because on the basis of existing rectangular cantilever beam, be provided with a window, make the semi-girder overall U-shaped, more narrow with the connecting portion of fixed pivot, therefore, it is compared with the rectangular cantilever beam that uses same process to produce, and sensitivity has improved near 2 times.2, the present invention is owing to be separately positioned on two resistance in the Wheatstone bridge on two semi-girders, one as measuring resistance, another is as reference resistance, rather than reference resistance is arranged on the substrate of chip, when therefore measuring, when external environmental noise made semi-girder deformation, this additional signals can be filtered by the reference semi-girder, makes measurement result more accurate.3, semi-girder of the present invention is the array arrangement, and with two adjacent semi-girders is one group, therefore can be by on semi-girder, being coated with different high molecule sensitivity layer, bioactive molecule, make each can finish a kind of measurement function by sensitive layer, and then measure when can realize different material various characteristics index to semi-girder.4, the present invention is in the manufacture craft of semi-girder, the contact hole that metal lead wire is connected with force sensing resistance, the arm of U-shaped semi-girder and the microflute on the chip adopt same mask plate definition, that is three mask plates have only been adopted in the present invention, compared to existing technology, the present invention has simplified technological process effectively.5, the present invention is owing to select for use gold as metal lead wire, therefore can resist long KOH corrosion, simultaneously owing to adopt KOH corroding method after the first scribing, avoided having discharged behind the semi-girder semi-girder damage that scribing again causes effectively, and then improved yield rate effectively.6, the present invention can design semi-girder, prepare in the flowable microflute of liquid by front etch technology and silicon～glass (polymkeric substance) bonding techniques, can be directly used in the detection of liquid biomolecule like this.

Description of drawings

Fig. 1 is a structural representation of the present invention

Fig. 2 is a Wheatstone bridge synoptic diagram of the present invention

Fig. 3 the present invention includes two one side semi-girder enlarged diagrams

Fig. 4 a～4j is a process flow diagram of the present invention

Embodiment

As shown in Figure 1 and Figure 2, the invention belongs to the pressure resistance type microsensor, it comprises a chip 1, and it is provided with a microflute 2, be provided with four groups of sensing units 3 in microflute 2 symmetria bilateralis, every group of sensing unit 3 comprises two semi-girders 4 and one group of Hui Sitong (Wheatstone) electric bridge 5.Every group of Wheatstone bridge 5 is made up of four identical force sensing resistance R1, R2, R3, R4, and wherein two resistance R 1, R4 are connected on two semi-girders 4, and semi-girder 4 ' is measured in a conduct, and another is as reference semi-girder 4 ".Again two other resistance R 2, R3 are connected on the substrate of chip 1.With reference resistance R4 design at reference semi-girder 4 " on, rather than to be arranged on chip 1 substrate be to consider when external environmental noise and hot mechanical shock noise make semi-girder 4 deformation, this additional signals can be by with reference to semi-girder 4 " filter.Traditional semi-girder is designed to rectangle more, in order to improve the measurement sensitivity of semi-girder, the present invention is according to calculating and simulated experiment, on the semi-girder of rectangle, opened a window 6, make it form a U-shaped semi-girder 4 (as shown in Figure 3), semi-girder 4 is connected with fixed pivot by two extension arms, and it is compared with the ordinary rectangular semi-girder, and sensitivity improves near 2 times.Different needs on semi-girder 4 ' surface according to measurement of species can be at the surperficial coating of measuring semi-girder 4 ' or growth high molecule sensitivity material, bioactive molecule or metal etc. as the sensitive layer (not shown).

Such as: at bioactive molecules such as semi-girder 4 ' the surperficial coating DNA, protein, realize micro-Recognition of Biomolecular such as DNA, protein by the specificity association reaction between reaction of the hydridization between dna molecular or protein.The sensor of measuring DNA is at the surperficial fixedly single strand dna of known array (being also referred to as the ssDNA probe) of semi-girder, detected biomolecule is the ssDNA molecule (being also referred to as target dna) of a complementation, both results of hydridization reaction form double-stranded DNA, power in the course of reaction makes the semi-girder bending, shows certain variation of output signals.The sensor of measuring protein is fixed on antibody the semi-girder surface usually, based on two kinds of intermolecular complementary structures and compatibility, form antigen antibody complex, it is crooked that antigen-antibody produces semi-girder in conjunction with (electric charge gravitation, Fan Denghua gravitation, hydrogen bonded power, hydrophobic adhesion).The slight curves of semi-girder 4 changes the resistance of force sensing resistance R1, biomolecule and the intermolecular reaction of sensitive layer that the differential voltage signal record is detected.

In the foregoing description, the design size of semi-girder 4 can be: long 50～500 μ m, wide 10～100 μ m, thick 100～5000nm, U-shaped brachium 20～200 μ m, wide 5～50 μ m.Four identical force sensing resistance sizes forming symmetrical Wheatstone bridge 5 can be: long 20～200 μ m, wide 5～50 μ m.After semi-girder is stressed, the moment M and the moment of inertia I of semi-girder depended in the distribution of stress, can prove that maximum stress usually occurs in the semi-girder surface, the meridional stress σ on release cantilever arm this moment and the power F of semi-girder end points and the pass of vertical displacement delta z are theoretically:

$\mathrm{\&sigma;}=\frac{9F(l_1+{\mathrm{<figure-callout\; id="2"\; label="l"\; filenames="A0310949100111.png"\; state="\{\{state\}\}">l</figure-callout>}}_2/2)}{{\mathrm{<figure-callout\; id="2"\; label="wt"\; filenames="A0310949100111.png"\; state="\{\{state\}\}">wt</figure-callout>}}^2}=\frac{9E(l_1+{\mathrm{<figure-callout\; id="2"\; label="l"\; filenames="A0310949100111.png"\; state="\{\{state\}\}">l</figure-callout>}}_2/2)t}{{12l}^3-{8l}_1^3}\mathrm{\&Delta;z}---\left(1\right)$

Wherein l is the length of semi-girder, l ₁Be the distance of semi-girder end points to U-shaped arm end, l ₂Be the length of U-shaped cantilever arm, w is the width of semi-girder, and t is the thickness of semi-girder, and E is a Young modulus.

If only consider meridional stress, relative change rate's Δ R/R of force sensing resistance can be provided by following formula:

$\frac{\mathrm{\&Delta;R}}{R}=\mathrm{\&sigma;\&pi;}---\left(2\right)$

Wherein π is vertical piezoresistance coefficient.Measure semi-girder because the effect of power when producing deformation, the change in resistance of semi-girder force sensing resistance is Δ R, and when bias voltage V acted on the Wheatstone electric bridge, the output signal of Wheatstone electric bridge was:

$V_o=\frac{V_{\mathrm{<figure-callout\; id="4"\; label="bias"\; filenames="A0310949100111.png,A0310949100121.png"\; state="\{\{state\}\}">bias</figure-callout>}}}{4}\frac{\mathrm{\&Delta;R}}{R}---\left(3\right)$

The measurement sensitivity definition of semi-girder is the relative variation of resistance and the ratio of semi-girder end points side-play amount.Stress result substitution formula (2) with (1) formula is calculated then can obtain the variation relation of the relative variation of resistance with power, and according to the definition of Hooke's law (Hook ' s) and elasticity coefficient, the measurement sensitivity of semi-girder can be expressed as:

$\frac{\mathrm{\&Delta;R}}{R}{\mathrm{\&Delta;z}}^{-1}=\frac{9\mathrm{E\&pi;}(l_1+{\mathrm{<figure-callout\; id="2"\; label="l"\; filenames="A0310949100111.png"\; state="\{\{state\}\}">l</figure-callout>}}_2/2)t}{{12l}^3-{8l}_1^3}=\frac{9K(l_1+{\mathrm{<figure-callout\; id="2"\; label="l"\; filenames="A0310949100111.png"\; state="\{\{state\}\}">l</figure-callout>}}_2/2)t}{{12l}^3-{8l}_1^3}---\left(4\right)$

E is a Young modulus in the formula, K=E π _lBe ga(u)ge factor, Δ z is the perpendicular displacement of semi-girder end points.

The signal noise ratio that the minimum detectable displacement (MDD) of the quick semi-girder of power is defined as semi-girder is the perpendicular displacement amount of 1: 1 condition lower cantalever beam, and it not only depends on the detection sensitivity of semi-girder, simultaneously the restriction of stressed quick resistance noise.Make Wheatston bridge output voltage signal V _oEqual overall noise, the MDD of semi-girder can be expressed as:

$\mathrm{MDD}=\frac{16({3l}^3-{2l}_1^3)}{3K(l_1+{\mathrm{<figure-callout\; id="2"\; label="l"\; filenames="A0310949100111.png"\; state="\{\{state\}\}">l</figure-callout>}}_2/2)t{V}_{\mathrm{bias}}}{[\frac{\mathrm{\&alpha;}{V}_{\mathrm{bias}}}{N}1n\frac{f_{\max }}{f_{\min }}+4k_B\mathrm{TR}(f_{\max }-f_{\min })]}^{1/2}---\left(5\right)$

In the following formula, first correspondence in the brace puted forth effort the 1/f noise of quick resistance, and second correspondence puted forth effort the Johnson noise of quick resistance.

Can be found out that by formula (5) noise and sensitivity are equilibrium process, the actual design size wants the combined process condition to select.The force sensing resistance size at first influences the noise of force sensing resistance, and the big more noise of size is more little.The semi-girder size influences the sensitivity and the noise of semi-girder equally,

The present invention has only adopted three mask plates by optimal design has been carried out in technological process in the making of micro-cantilever, compare other method for making, has carried out bigger simplification in technological process.Be making of the present invention below

Embodiment:

1, make chip substrate, it can adopt monocrystalline silicon or polysilicon dual mode,

When (1) making the polysilicon semi-girder, can buy single-sided polishing p type silicon chip 10, silicon chip 10 is carried out routine cleaning after, carry out plasma enhanced CVD (PECVD) silicon nitride (Si on silicon chip 10 surfaces ₃N ₄) 11 (shown in Fig. 4 a), being used to seal the bottom of force sensing resistance, thickness is 150nm; Low pressure chemical vapor deposition (LPCVD) polysilicon 12 (shown in Fig. 4 b) then, thickness is 200nm, forms polysilicon force sensing resistance layer.

When (2) making the single-crystal silicon cantilever beam, adopt SOI (silicon structure on the insulator) silicon chip, its surface is handled, the attenuate device layer, oxidated layer thickness is: 400nm, device layer thickness is: 200nm, device layer are monocrystalline silicon force sensing resistance layer.

2, the monocrystalline silicon that will handle through step 1 or polysilicon silicon chip inject 13 (shown in Fig. 4 c) that mix as chip substrate to its front boron ion, and the concentration of injecting the boron ion is 5 * 10 to polysilicon ¹⁵Cm ^-2, be 5 * 10 to monocrystalline silicon ¹⁴Cm ^-2, inject energy 30keV.

3, adopt mask plate to carry out the figure conversion of force sensing resistance, monocrystalline silicon or polysilicon after mixing are carried out SF ₆(sulfur hexafluoride) reactive ion etching (RIE) forms force sensing resistance R (shown in Fig. 4 d).

4, be the quick resistance R of complete sealing force, plasma enhanced CVD silicon nitride 11 (shown in Fig. 4 e), deposition thickness 150nm is then at N ₂In 1050 ℃ annealing 20 minutes.

5, adopting microflute, contact hole, U-shaped semi-girder is that the mask plate of one carries out photoetching (shown in Fig. 4 f), to Si ₃N ₄Carry out CHF ₃+ SF ₆(fluoroform+sulfur hexafluoride) reactive ion etching etches away the Si on microflute 14 and the force sensing resistance contact hole 15 ₃N ₄, etch away the Si of U-shaped semi-girder window simultaneously ₃N ₄

6, by electron beam transpiration chromium/gold (Cr/Au) thermometal film 16 (shown in Fig. 4 g), chromium thickness is 40nm, is used for making gold preferably attached on the substrate, and golden thickness 400nm adopts gold rather than aluminium to be because the corrosion that gold can be resisted potassium hydroxide (KOH).

7, adopt metal mask plate (shown in Fig. 4 h), after the photoetching, corroding metal is finished the shaping of metal wire 17;

8, carry out the scribing (shown in Fig. 4 i) of single-sensor on entire chip 1, first scribing guarantees not damage semi-girder in the scribing processes before carrying out the potassium hydroxide corrosion.

9, carry out potassium hydroxide corrosion, discharge semi-girder (shown in Fig. 4 j), utilize the character of potassium hydroxide to the anisotropy salient angle corrosion of silicon, under sufficiently long etching time, the silicon below the semi-girder can corrode totally the about 60 μ m of the groove depth after the corrosion fully.

10, metal and silicon in the force sensing resistance contact hole are carried out Alloying Treatment, make them form Ohmic contact, alloy condition: 320 ℃, 20 minutes.

11, be single-sensor with entire chip from above-mentioned scribing sliver.

12, a semi-girder in per two semi-girders is promptly measured semi-girder 4 ' the surperficial coating sensitive layer.

In the said method, wherein

Step 1, when silicon chip surface carried out the plasma enhanced CVD silicon nitride, its thickness can be 100～1000nm; The oxidated layer thickness of soi wafer can be 200～800nm, and device layer thickness can be 100～500nm.

Step 1, low pressure chemical vapor deposition polysilicon are during as the force sensing resistance layer, and its thickness can be 100～500nm; The thickness of silicon nitride or monox protective seam has determined the thickness of semi-girder, and the thickness of semi-girder has determined its sensitivity, can be found out by formula (4).

Step 2 is injected when mixing monocrystalline silicon or polysilicon front boron ion, and the concentration of injecting the boron ion can be 5 * 10 ¹³Cm ^-2～5 * 10 ¹⁵Cm ^-2, energy 30keV～80keV; Doping content is high more, and the noise of semi-girder is low more, but sensitivity reduces simultaneously.Ion implantation energy determines the depth that the boron ion spreads in resistive layer, thereby influences the sensitivity of semi-girder.

Step 4, during the plasma enhanced CVD silicon nitride, deposition thickness can be 100～1000nm, then in nitrogen 900～1100 ℃ annealing 20～30 minutes; Thickness has determined the thickness of semi-girder, and the thickness of semi-girder has determined its sensitivity, can be found out by formula (4).

Step 5, the thickness of chromium/golden thermometal film can suitably be adjusted.

In the above-mentioned method for making, after the chip photoetching, no matter be etching in gas, still in liquid, corrode that its employed gas or liquid all can change as required.

In the foregoing description, the quantity of semi-girder 4 can be according to the needs setting of the project of measurement, but its quantity should be even number, promptly two semi-girders are one group, form a sensing unit independently with four force sensing resistances that on two semi-girders and chip substrate, are provided with, finish a measurement project, therefore, have two semi-girders on the chip, just can form a sensor; If many group semi-girders are set, then form array-type sensor, sensor can not be provided with microflute, makes semi-girder be positioned at a side (as shown in Figure 3) of chip, also microflute can be set, and makes semi-girder be positioned at microflute both sides (as shown in Figure 1).

The present invention can design semi-girder, prepare in the flowable microflute of liquid by front etch technology and silicon～glass (polymkeric substance) bonding techniques, can be directly used in the detection of liquid biomolecule like this.

No matter the modular or array pressure drag semi-girder of the present invention is to be applied on the gas sensor, or on the biology sensor, all will reduce device size, improve device sensitivity and realize playing a significant role on the multifunctionality of sensor.The beam type sensor is in environmental monitoring, and fields such as clinical diagnosis and treatment, new drug development, food security, industrial processes control, military affairs are with a wide range of applications.

Claims (15)

1, a kind of micro-cantilever beam sensor, it comprises a chip, it is characterized in that: described chip is provided with at least one group of sensing unit, described sensing unit is made up of four identical force sensing resistances and two semi-girders of forming Wheatstone bridge, wherein two described resistance are positioned on the substrate of described chip, two other lays respectively on described two semi-girders, one of them is as measuring semi-girder, another is as the reference semi-girder, has a window on each described semi-girder, described semi-girder is taken the shape of the letter U be arranged on the described chip, described measurement semi-girder surface is provided with sensitive layer.

2, a kind of micro-cantilever beam sensor as claimed in claim 1 is characterized in that: described sensing unit is a plurality of.

3, a kind of micro-cantilever beam sensor as claimed in claim 1 or 2 is characterized in that: the semi-girder of described sensing unit is arranged on a side of described chip.

4, a kind of micro-cantilever beam sensor as claimed in claim 1 or 2, it is characterized in that: described chip is provided with a microflute, and the semi-girder of described sensing unit is arranged on described microflute both sides.

5, a kind of micro-cantilever beam sensor as claimed in claim 1 or 2 is characterized in that: described sensitive layer is the high molecule sensitivity material.

6, a kind of micro-cantilever beam sensor as claimed in claim 1 or 2 is characterized in that: described sensitive layer is a bioactive molecule.

7, a kind of micro-cantilever beam sensor as claimed in claim 1 or 2 is characterized in that: described length of cantilever 50～500 μ m, wide 10～100 μ m, thick 100～5000nm, U-shaped brachium 20～200 μ m of described window both sides, wide 5～50 μ m.

8, a kind of micro-cantilever beam sensor as claimed in claim 1 or 2 is characterized in that: described force sensing resistance is of a size of long 20～200 μ m, wide 5～50 μ m.

9, a kind of method for making of micro-cantilever beam sensor is characterized in that it may further comprise the steps:

(1) adopt soi wafer, and the attenuate device layer is as chip substrate with oxide layer, single-crystal silicon device layer; Perhaps adopt single-sided polishing p type silicon chip, carry out after routine cleans, at silicon chip surface plasma enhanced CVD silicon nitride, then at silicon nitride surface low pressure chemical vapor deposition polysilicon as chip substrate;

(2) monocrystalline silicon or the injection of polysilicon front boron ion are mixed;

(3) with mask plate the chip through step (2) is carried out the photoetching first time,, form force sensing resistance through etching;

(4) chip surface through step (3) is passed through the plasma enhanced CVD silicon nitride, then in AN;

(5) with mask plate the chip through step (4) is carried out the photoetching second time,, form the arm and the window of force sensing resistance contact hole and U-shaped semi-girder through etching;

(6) chip surface through step (5) is passed through electron beam, sputter chromium/golden thermometal film;

(7) with mask plate the chip through step (6) is carried out photoetching for the third time,, form the metal wire that connects each force sensing resistance through corrosion;

(8) on entire chip, carry out the scribing of single-sensor;

(9) with the chip of potassium hydroxide corrosion, discharge semi-girder through step (8);

(10) metal wire in the force sensing resistance contact hole on the chip and chip substrate are carried out alloy treatment;

(11) be single-sensor with the entire chip sliver;

(12) a semi-girder surface in per two semi-girders is provided with sensitive layer.

10, the method for making of a kind of micro-cantilever beam sensor as claimed in claim 9 is characterized in that: step (5) wherein forms the microflute on the chip in arm that forms force sensing resistance contact hole and U-shaped semi-girder and window.

11, the method for making of a kind of micro-cantilever beam sensor as claimed in claim 9 is characterized in that: step (1) wherein, and the oxidated layer thickness of soi wafer is 200～800nm, device layer thickness is 100～500nm.

12, the method for making of a kind of micro-cantilever beam sensor as claimed in claim 9 is characterized in that: step (1) wherein, when silicon chip surface carried out the plasma enhanced CVD silicon nitride, the thickness of silicon nitride was 100～1000nm.

13, the method for making of a kind of micro-cantilever beam sensor as claimed in claim 9 is characterized in that: step (1) wherein, when the low pressure chemical vapor deposition polysilicon, the thickness of polysilicon is 100～500nm.

14, the method for making of a kind of micro-cantilever beam sensor as claimed in claim 9 is characterized in that: step (2) wherein, monocrystalline silicon or polysilicon front boron ion to be injected when mixing, and the concentration of injecting the boron ion is 5 * 10 ¹³Cm ^-2～5 * 10 ¹⁵Cm ^-2, inject energy 30keV～80keV.

15, the method for making of a kind of micro-cantilever beam sensor as claimed in claim 9, it is characterized in that: step (4) wherein, during the plasma enhanced CVD silicon nitride, silicon nitride thickness is 100～1000nm, then in nitrogen 900～1100 ℃ annealing 20～30 minutes.

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