CN100503245C - Liquid-jet head and liquid-jet apparatus - Google Patents

Abstract

The invention discloses a liquid injection head and a liquid injector ensuring stabilized liquid ejection characteristics. The liquid injection head comprises a channel forming substrate in which a plurality of pressure generating chambers communicating with nozzle openings for injecting liquid are formed, a piezoelectric element provided in a region facing the pressure generating chamber on one side of the channel forming substrate through a diaphragm and consisting of a lower electrode, a piezoelectric layer and an upper electrode, a lead electrode being led out from the upper electrode, and a lead electrode being led out from the lower electrode. The lower electrode is a common electrode provided continuously in a region facing the plurality of juxtaposed pressure generating chambers, and at least one end part of the lower electrode in the direction orthogonally intersecting the juxtaposing direction of the pressure generating chambers is located in a region facing the pressure generating chambers. The lead electrode for the lower electrode is provided on the outside of a region corresponding to the space between the pressure generating chambers and connected through a common lead part extended from the lower electrode. Alternatively, the lead electrode for the lower electrode is composed of an adhesion layer and a metal layer, and only the adhesion layer is extended to reach the lower electrode.

Description

Fluid jetting head and liquid injection device

Technical field

The present invention relates to the fluid jetting head and the liquid injection device of atomizing of liquids, more specifically, the present invention relates to spray the ink jet print head and the ink jet recording device of ink droplet.

Background technology

In ink jet print head, the part of the pressure generation chamber that is communicated with nozzle bore is formed by oscillating plate, by make this oscillating plate distortion with piezoelectric element, the ink in the pressure generation chamber is exerted pressure, thereby eject ink droplet from nozzle bore.Two kinds of ink jet print heads are come into operation, wherein a kind of use piezoelectric element axially on elongation and the longitudinal vibration mode piezo-activator that shrinks; A kind of piezo-activator that uses beam mode.

As back a kind of ink jet print head of the actuator of using beam mode, for example known formed as described below a kind of.Particularly, by using deposition technique to form even piezoelectric material layer on the whole surface of oscillating plate.After this, by using photoetching method that this piezoelectric material layer is cut into and the corresponding shape of pressure generation chamber.Like this, independently form piezoelectric element for each pressure generation chamber.

At this, so wherein piezoelectric element by the ink jet print head of dense arrangement in, an electrode (public electrode) of each piezoelectric element is configured to by a plurality of piezoelectric elements shared.Therefore, sprayed a large amount of ink droplets if drive simultaneously at a large amount of piezoelectric elements of certain time, then the voltage drop of piezoelectric element and displacement become unstable.As a result, the problem that the inkjet performance fluctuation occurs.

Therefore, proposed a kind of ink jet print head, having comprised: the common lead electrode, it is drawn out to the outside in the face of the zone of pressure generation chamber by the part except that the end of the orientation of pressure generation chamber from public electrode; And the resistance that comprises the connection distribution that is formed by closing line reduces part (for example, referring to patent document 1).Above-mentioned ink jet print head reduces the common electrode resistance value by allowing resistance to reduce part when voltage is applied to piezoelectric element, can prevent because the fluctuation of the inkjet performance that voltage drop causes.

But, reducing in the ink jet print head of part at aforesaid common lead electrode and the resistance of comprising, public electrode is different members with the common lead electrode.Therefore, when being connected to the common lead electrode of public electrode, can produce foozle by the formation of use deposition technique.For example, because the skew of mask or etching condition, the size such as width of common lead electrode produces slight fluctuation, and perhaps slight skew takes place in the formation position of common lead electrode.Therefore, the common lead electrode is from the partition wall perpendicular to the both sides of the orientation of pressure generation chamber is projected into zone in the face of pressure generation chamber.As a result, following problem occurs, promptly the rigidity of oscillating plate is increased by the part and causes inkjet performance to fluctuate.

And, known following ink jet print head, it comprises the common lead electrode (for example, referring to patent document 2) that is drawn out to from public electrode in the face of the outside in the zone of pressure generation chamber.In above-mentioned ink jet print head, public electrode is formed with the common lead electrode has identical pattern.Therefore, can address the problem, promptly under the situation that above-mentioned wherein public electrode and common lead electrode are formed separately, thereby the common lead electrode is projected into the fluctuation that causes inkjet performance in the zone in the face of pressure generation chamber.

But the ink jet print head with said structure has the voltage drop that can not fully prevent generation when a plurality of piezoelectric elements are driven simultaneously.More specifically, the thickness that can increase public electrode prevents voltage drop.But, because public electrode generally forms the part of oscillating plate, thus if the thickness of public electrode increases, then since the amount of the distortion of the oscillating plate that the driving of piezoelectric element causes reduce.Therefore, need to form thin public electrode.On the other hand, if the thickness of public electrode reduces, then resistance value increases.Therefore, existence may cause because the contradiction of the problem of the inkjet performance fluctuation that voltage drop causes.Therefore, have wherein above-mentioned that public electrode and common lead electrode are formed in the ink jet print head of the structure with identical patterns, the thickness of common lead electrode and the thickness of public electrode are reduced and cause voltage drop.Therefore, the problem that the inkjet performance fluctuation occurs.Notice that what need not many speeches is that above-mentioned similar problem does not exist only in the ink jet print head that sprays ink droplet, and is present in other fluid jetting heads that spray the liquid that is different from ink droplet.

Patent document 1: the Japan Patent spy opens No.2004-1366 (Fig. 1 and 2)

Patent document 2: the Japan Patent spy opens No.2003-127358 (Fig. 3)

Summary of the invention

The problem to be solved in the present invention

Consider above-mentioned situation, an object of the present invention is to provide the fluid jetting head and the liquid injection device that can obtain stable liquid jet performance.

The means of dealing with problems

Be used to realize that a first aspect of the present invention of aforementioned purpose is a kind of fluid jetting head, comprise: passage forms substrate, wherein is formed with a plurality of pressure generation chambers that are communicated with the nozzle bore of atomizing of liquids; Piezoelectric element, it is set at described passage and forms above substrate one side in the zone of described pressure generation chamber and oscillating plate is placed in described piezoelectric element and described passage forms between the substrate, and each in the described piezoelectric element comprises bottom electrode, piezoelectric layer and top electrode; Top electrode lead-in wire electrode, it is drawn from described top electrode; Bottom electrode lead-in wire electrode, it is drawn from described bottom electrode.In described fluid jetting head, described bottom electrode is arranged on described in the face of the public electrode in the zone of a plurality of pressure generation chambers through arranging continuously.In addition, the end at least one side on the direction vertical with orientation described pressure generation chamber described bottom electrode is arranged in described zone in the face of pressure generation chamber.And described bottom electrode has the common lead part, described common lead part by from and described pressure generation chamber between corresponding zone, space an end be drawn out to outside the corresponding zone, space between described and the adjacent pressure generation chamber.And described bottom electrode is electrically connected to the described common lead part of described bottom electrode with the lead-in wire electrode.In addition, in the exterior lateral area of described bottom electrode with the corresponding zone, space of coupling part between described and pressure generation chamber between lead-in wire electrode and the described common lead part.

In first aspect, bottom electrode with the coupling part between lead-in wire electrode and the common lead part be set at be in and pressure generation chamber between the zone in the outside in corresponding zone, space in.Therefore, can prevent reliably bottom electrode with the lead-in wire electrode owing to foozle is formed in the zone in the face of pressure generation chamber.And bottom electrode is partly drawn by the further common lead from bottom electrode with the lead-in wire electrode, and the resistance value of bottom electrode is reduced.Therefore, for example, be formed traditional structure with common lead electrode wherein with public electrode and compare, can prevent the voltage drop when a plurality of piezoelectric elements are driven simultaneously reliably with identical patterns.Therefore, can obtain stable liquid jet performance.

A second aspect of the present invention is as the described fluid jetting head of first aspect, it is characterized in that the end of described piezoelectric element at least one side on its direction vertical with the orientation of described pressure generation chamber extends to the zone right with the peripheral wall of described pressure generation chamber from described zone in the face of pressure generation chamber.And, described bottom electrode with the coupling part between described one the described common lead part on distolateral of lead-in wire electrode and described piezoelectric element and described piezoelectric element between the exterior lateral area in corresponding zone, space in.

In second aspect, bottom electrode with the coupling part between lead-in wire electrode and the common lead part and extend to and the piezoelectric element in the zone that the peripheral wall of pressure generation chamber is right between the outside in corresponding zone, space.Therefore, can obtain stable liquid jet performance more reliably.

A third aspect of the present invention is as one of any described fluid jetting head in first and second aspects, it is characterized in that, the public electrode pattern that is connected to described bottom electrode is arranged on as in the lower area along the orientation of described pressure generation chamber, described zone be in described in the face of in the zone of a plurality of pressure generation chambers through arranging with the outside of described bottom electrode with lead-in wire electrode opposite end.

In the third aspect, the resistance value of bottom electrode can further be reduced, and can prevent voltage drop more reliably.

A fourth aspect of the present invention is as the described fluid jetting head of the third aspect, it is characterized in that, described common lead part is also drawn from the end of the opposite side of described bottom electrode arrives described public electrode pattern.

In fourth aspect, the resistance value of bottom electrode can further be reduced, and can prevent voltage drop more reliably.

A fifth aspect of the present invention is as the described fluid jetting head of the third aspect, it is characterized in that described bottom electrode is provided with continuously, to arrive described public electrode pattern from described zone in the face of a plurality of pressure generation chambers through arranging.

In aspect the 5th, the resistance value of bottom electrode can further be reduced, and can prevent voltage drop more reliably.

A sixth aspect of the present invention is as one of any described fluid jetting head in the 3rd to the 5th aspect, it is characterized in that, described piezoelectric element is arranged in described zone in the face of pressure generation chamber in the other end with the corresponding side of described public electrode pattern.

In aspect the 6th, extend in the face of the situation in the zone of the peripheral wall of pressure generation chamber with the other end of piezoelectric element and to compare, can increase with respect to passage and form whole surface on the side of substrate, the ratio of public electrode pattern area occupied.Therefore, can prevent voltage drop more reliably.

A seventh aspect of the present invention is as one of any described fluid jetting head in first to the 6th aspect, it is characterized in that, described bottom electrode is formed by adhesion layer and metal level with the lead-in wire electrode, described adhesion layer is made by adhesiving metal, and described metal level is made and is arranged on the described adhesion layer by metal material.And described adhesion layer extends the described end on the described side that arrives described bottom electrode, and described bottom electrode is electrically connected to each other with electrode and the described bottom electrode adhesion layer by described extension that goes between.

In aspect the 7th, bottom electrode can further be reduced with the resistance value of the coupling part between lead-in wire electrode and the bottom electrode.

A eighth aspect of the present invention is as one of any described fluid jetting head in first to the 7th aspect, it is characterized in that, at least each layer that forms described piezoelectric element used the described coupling part that goes between between electrode and the described common lead part except described bottom electrode, and the dielectric film of all being made by inorganic insulating material covers.And described bottom electrode is drawn out on the described dielectric film with the lead-in wire electrode.

In eight aspect, because piezoelectric layer is covered by having the dielectric film that the infiltrative inorganic insulating material of low moisture makes, so prevented the deterioration (destruction) of the piezoelectric layer (piezoelectric element) that causes by moisture (humidity) in long-time reliably.

Be used to realize that a ninth aspect of the present invention of aforementioned purpose is a kind of fluid jetting head, comprise: passage forms substrate, wherein is formed with a plurality of pressure generation chambers that are communicated with the nozzle bore of atomizing of liquids; Piezoelectric element, it is set at described passage and forms above substrate one side in the zone of described pressure generation chamber and oscillating plate is placed in described piezoelectric element and described passage forms between the substrate, and each in the described piezoelectric element comprises bottom electrode, piezoelectric layer and top electrode; Top electrode lead-in wire electrode, it is connected to described top electrode; Bottom electrode lead-in wire electrode, it is connected to described bottom electrode.In described fluid jetting head, described bottom electrode is arranged on described in the face of the public electrode in the zone of a plurality of pressure generation chambers through arranging continuously.In addition, the end at least one side on the direction vertical with orientation described pressure generation chamber described bottom electrode is arranged in described zone in the face of pressure generation chamber.And described bottom electrode is formed by adhesion layer and metal level with the lead-in wire electrode, and described adhesion layer is made by adhesiving metal, and described metal level is made and is arranged on the described adhesion layer by metal material.And, described bottom electrode with the lead-in wire electrode and described pressure generation chamber between the exterior lateral area in corresponding zone, space in.In addition, the described bottom electrode of described formation extends described end on the described side that arrives described bottom electrode with the adhesion layer of lead-in wire electrode, and described bottom electrode is electrically connected to each other with electrode and the described bottom electrode adhesion layer by described extension that goes between.

In aspect the 9th, because adhesion layer is relatively thin film, so even adhesion layer is because foozle is projected in the zone in the face of pressure generation chamber, the rigidity of oscillating plate also changes hardly.And, because bottom electrode with the lead-in wire electrode be set at be in and pressure generation chamber between the zone in the outside in corresponding zone, space in, so metal level can be owing to foozle is formed in the zone in the face of pressure generation chamber yet.Therefore, the inkjet performance fluctuation that takes place in the time of can preventing reliably in the common lead electrode is projected in the face of the zone of pressure generation chamber as in the conventional art situation.And, by bottom electrode is connected to bottom electrode with the lead-in wire electrode, reduced the resistance value of bottom electrode.Therefore, for example, be formed the traditional structure with identical patterns with common lead electrode wherein with public electrode and compare, the voltage drop when a plurality of piezoelectric elements are driven simultaneously can be prevented reliably.Thereby, can obtain stable liquid jet performance.

A tenth aspect of the present invention is as the described fluid jetting head in the 9th aspect, it is characterized in that, the thickness of described adhesion layer is equal to or less than the thickness of described bottom electrode, and described metal layer thickness is greater than the thickness of described bottom electrode.

In aspect the tenth, can obtain more stable liquid jet performance.

A eleventh aspect of the present invention is as one of any described fluid jetting head in the 9th and the tenth aspect, it is characterized in that, the public electrode pattern that is connected to described bottom electrode is arranged on as in the lower area along the orientation of described pressure generation chamber, described zone be in described in the face of in the zone of a plurality of pressure generation chambers through arranging with the outside of described bottom electrode with lead-in wire electrode opposite end.

In the tenth one side, can further reduce the resistance value of bottom electrode, and can prevent voltage drop more reliably.

A twelveth aspect of the present invention is as the described fluid jetting head of the tenth one side, it is characterized in that, described adhesion layer extends the described public electrode pattern of arrival from described bottom electrode with the lead-in wire electrode, and described bottom electrode is connected to each other with electrode and the described public electrode pattern adhesion layer by described extension that goes between.

In aspect the 12, the resistance value of bottom electrode can be further reduced, and voltage drop can be prevented more reliably.

A thirteenth aspect of the present invention is as one of any described fluid jetting head in the 9th to the 12 aspect, it is characterized in that, described adhesion layer is arranged in the zone of facing with the partition wall of described a plurality of pressure generation chambers through arranging each, and each adhesion layer has identical pattern at least in described and zone that the partition wall of pressure generation chamber is faced.

In aspect the 13, the vibration characteristics of oscillating plate is a homogeneous in each piezoelectric element.Therefore, can prevent the fluctuation of liquid jet performance reliably.

A fourteenth aspect of the present invention is as the described fluid jetting head in the 13 aspect, it is characterized in that, extends with the lead-in wire electrode from described bottom electrode one of in described a plurality of adhesion layers, and remaining is the empty electrode that is only formed by described adhesion layer.

In aspect the 14, the vibration characteristics of oscillating plate is a homogeneous in each piezoelectric element, has prevented voltage drop simultaneously reliably.Therefore, can prevent the fluctuation of liquid jet performance more reliably.

A fifteenth aspect of the present invention is as one of any described fluid jetting head in the 9th to the 14 aspect, it is characterized in that, described bottom electrode has the common lead part, and described common lead part is drawn out to described bottom electrode with the lead-in wire electrode by the described end from the described side of described bottom electrode.And described bottom electrode is connected to each other by the described adhesion layer that is arranged on the described common lead part with lead-in wire electrode and described bottom electrode.

In aspect the 15, the formation bottom electrode is set on the common lead part with the adhesion layer of lead-in wire electrode.Therefore, can guarantee fully that bottom electrode and bottom electrode are with the be connected to each other thickness of part at place of lead-in wire electrode.And, can prevent voltage drop more reliably.

A sixteenth aspect of the present invention is as one of any described fluid jetting head in the first to the 15 aspect, it is characterized in that, at least each layer that forms described piezoelectric element is except the coupling part between described bottom electrode and the described adhesion layer, and the dielectric film of all being made by inorganic insulating material covers.

In aspect the 16, because piezoelectric layer is covered by having the dielectric film that the infiltrative inorganic insulating material of low moisture makes, so prevented the deterioration (destruction) of the piezoelectric layer (piezoelectric element) that causes by moisture (humidity) in long-time reliably.

A seventeenth aspect of the present invention is a kind of liquid injection device, and it comprises any one described fluid jetting head of the 9th to the 16 aspect.

In aspect the 17, can obtain stable liquid jet performance, and can be relatively easily and realize liquid injection device with excellent reliability reliably.

Description of drawings

Fig. 1 is the decomposition diagram according to the record head of embodiment 1.

Fig. 2 (a) and 2 (b) are vertical view and the cutaway views according to the record head of embodiment 1.

Fig. 3 (a) and 3 (b) are vertical view and the cutaway views according to the amplification of the major part of the record head of embodiment 1.

Fig. 4 is the vertical view according to the amplification of the major part of the record head of embodiment 2.

Fig. 5 (a) and 5 (b) are vertical view and the cutaway views according to the amplification of the major part of the record head of embodiment 3.

Fig. 6 is the vertical view according to the amplification of the major part of another record head of embodiment 3.

Fig. 7 is the vertical view according to the amplification of the major part of another record head of embodiment 4.

Fig. 8 is the vertical view according to the amplification of the major part of another record head of embodiment 5.

Fig. 9 is the decomposition diagram according to the record head of embodiment 6.

Figure 10 (a) and 10 (b) are vertical view and the cutaway views according to the record head of embodiment 6.

Figure 11 (a) and 11 (b) are vertical view and the cutaway views according to the amplification of the major part of the record head of embodiment 6.

Figure 12 (a) and 12 (b) are vertical view and the cutaway views according to the amplification of the major part of the record head of embodiment 7.

Figure 13 is the schematic diagram according to the recording equipment of embodiment.

Label declaration:

10 passages form substrate

12 pressure generation chambers

13 connected components

14 ink feed paths

20 nozzle plates

21 nozzle bores

30 baffles

31 piezoelectric element retaining parts

32 fluid reservoir parts

40 flexible boards

50 elastic membranes

60 lower electrode film

65 common lead parts

70 piezoelectric layers

80 upper electrode films

90 top electrodes lead-in wire electrode

95 bottom electrodes lead-in wire electrode

100 dielectric films

110 fluid reservoirs

120 drive IC

130 common electrode layer

140 public electrode patterns

200 coupling parts (corresponding to the coupling part of first contact hole)

250 coupling parts (corresponding to the coupling part of second contact hole)

300 piezoelectric elements

The specific embodiment

To describe the present invention in detail by embodiment below.

(embodiment 1)

Fig. 1 shows the decomposition diagram according to the ink jet print head of the embodiment of the invention 1.Fig. 2 (a) is the vertical view according to the ink jet print head of embodiment 1, and Fig. 2 (b) is the cutaway view along the line A-A ' among Fig. 2 (a).Fig. 3 (a) is the vertical view according to the amplification of the major part of the ink jet print head of embodiment 1, and Fig. 3 (b) is the cutaway view along the line B-B ' among Fig. 3 (a).As shown in these figures, the substrate 10 of passage formation is in the present embodiment made by the monocrystalline substrate with (110) planar orientation, and forming thickness on a surface of passage formation substrate 10 is the elastic membrane 50 of 0.5 μ m to 2 μ m, and this elastic membrane 50 is by making by the preformed silicon dioxide film of thermal oxide.In passage forms substrate 10, be arranged with a plurality of pressure generation chambers 12, described pressure generation chamber 12 is by carrying out from another surface of substrate that anisotropic etching forms and being separated by partition wall 11.

And, connected component 13 be formed on each pressure generation chamber 12 perpendicular in the exterior lateral area on the orientation direction of (laterally) (vertically), described connected component 13 forms the part as the fluid reservoir 110 of the common ink water cavity of each pressure generation chamber 12.Connected component 13 is communicated with end longitudinally of each pressure generation chamber 12 respectively by ink feed path 14.And, have the littler cross-sectional area of cross-sectional area that specific pressure produces chamber 12 with in the ink feed path 14 that an end of each pressure generation chamber 12 is communicated with each to be formed, and the channel resistance that makes the ink feed pressure produce chamber 12 keeps constant.

In addition, nozzle plate 20 is fixed to the open surfaces side that passage forms substrate 10, on nozzle plate 20, is drilled with nozzle bore 21 by bonding agent, hot melt film etc.Particularly, be communicated with near nozzle bore 21 and each pressure generation chamber 12 and ends ink feed path 14 opposite sides.Notice that nozzle plate 20 is made by glass ceramics, monocrystalline substrate, stainless steel etc., this glass ceramics for example has from the thickness of 0.01mm to 1mm and for example is being less than or equal under 300 ℃ the temperature from 2.5 to 4.5 * [10 ^-6/ ℃] linear expansion coefficient.And nozzle plate 20 can form by having the material that forms the roughly the same thermal coefficient of expansion of substrate 10 with passage.

Simultaneously, as previously mentioned, on a side opposite of passage formation substrate 10, form the elastic membrane 50 that thickness for example is about 1.0 μ m with open surfaces.On elastic membrane 50, form the dielectric film 55 that thickness for example is about 0.4 μ m.In addition, stacked thickness for example is about the upper electrode film 80 that the lower electrode film 60 of 0.2 μ m, piezoelectric layer 70 that thickness for example is about 1.0 μ m and thickness for example are about 0.05 μ m on dielectric film 55, thereby forms piezoelectric element 300.

At this, piezoelectric element 300 refers to the part that comprises lower electrode film 60, piezoelectric layer 70 and upper electrode film 80.Generally speaking, by using in its electrode any one, form piezoelectric element 300 as public electrode and corresponding to each another electrode of pressure generation chamber 12 patternings and piezoelectric layer 70.Thereby, at this, comprise any one electrode that is patterned and piezoelectric layer 70 and wherein be called as the piezoelectric activity part by the part that these two electrode application voltage are produced piezoelectric strain.

And at this, the oscillating plate that piezoelectric element 300 and the driving by piezoelectric element 300 produce displacement is called piezo-activator together.Notice that in the above-described embodiments, elastic membrane 50, dielectric film 55 and lower electrode film 60 are served as oscillating plate.

Note,, can use the relaxation ferroelectric material that forms by in ferroelectric (piezoelectricity) material that will join lead zirconate titanate (PZT) for example etc. such as the metal niobium, nickel, magnesium, bismuth yttrium and the ytterbium as the material of piezoelectric layer 70.Characteristic, the application that can consider piezoelectric element wait correspondingly selection component.For example, can enumerate PbTiO ₃(PT), PbZrO ₃(PZ), Pb (Zr _xTi _{1- x}) O ₃(PZT), Pb (Mg _1/3Nb _2/3) O ₃-PbTiO ₃(PMN-PT), Pb (Zn _1/3Nb _2/3) O ₃-PbTiO ₃(PZN-PT), Pb (Ni _1/3Nb _2/3) O ₃-PbTiO ₃(PNN-PT), Pb (In _1/2Nb _1/2) O ₃-PbTiO ₃(PIN-PT), Pb (Sc _1/2Ta _1/2) O ₃-PbTiO ₃(PST-PT), Pb (Sc _1/2Nb _1/2) O ₃-PbTiO ₃(PSN-PT), BiScO ₃-PbTiO ₃(BS-PT) and BiYbO ₃-PbTiO ₃(BY-PT) etc.

At this, be provided at continuously on the zone in the face of a plurality of pressure generation chambers 12 through arranging as the lower electrode film 60 of the public electrode of above-mentioned piezoelectric element 300.More specifically, lower electrode film 60 is provided at whole zone in the face of pressure generation chamber 12 continuously and is in the relative zone of partition wall 11 on the both sides in the orientation of pressure generation chamber 12 with orientation along pressure generation chamber.And in this embodiment, the two ends perpendicular on the direction of the orientation of pressure generation chamber 12 of lower electrode film 60 lay respectively in the zone in the face of pressure generation chamber 12.

Above-mentioned lower electrode film 60 has common lead part 65 (referring to Fig. 3 (a) and 3 (b)), described common lead part 65 by from and end at least one side in the corresponding zone, space between two pressure generation chambers 12 in the orientation of pressure generation chamber 12 (in this embodiment, the utmost point is with the end of lead-in wire electrode 90 side of being drawn from it from power on), be drawn out to and adjacent pressure generation chamber 12 between the outside in corresponding zone, space.And above-mentioned common lead part 65 is drawn out to by the common lead part 65 from lower electrode film 60 and top electrode is used near the corresponding zone, space (passage forms the end of substrate 10) that goes between between the electrode 90.Notice that the width of common lead part 65 is formed to be narrower than the width of each partition wall 11 on the both sides of pressure generation chamber 12 widths.For example, in this embodiment, the width of partition wall 11 is set as about 15 μ m, and the width of common lead part 65 is for being made as about 4 μ m.

And in this embodiment, piezoelectric layer 70 and upper electrode film 80 are set on the orientation of pressure generation chamber 12 in the zone to pressure generation chamber 12.But piezoelectric layer 70 and upper electrode film 80 are extended the outside of the end of lower electrode film 60 on the direction vertical with the orientation of pressure generation chamber 12.In addition, two of lower electrode film 60 end surfaces are covered by piezoelectric layer 70.And in this embodiment, each piezoelectric element 300 extends to the zone in the face of the peripheral wall on the two ends of the direction vertical with the orientation of pressure generation chamber 12.Thereby, will be formed on as the piezoelectric activity part 330 of the actual drive part of piezoelectric element 300 in the approximate centre part of pressure generation chamber 12.Near the two ends of piezoelectric activity part, form piezoelectricity passive part 340 (seeing Fig. 2 (a)), it is continuous with piezoelectric activity part 330, and has piezoelectric layer 70 and upper electrode film 80, still in fact is not driven.

In addition, in this embodiment, use the dielectric film of making by inorganic insulating material 100 to cover as the area of the pattern in the zone of arranging above-mentioned piezoelectric element 300.At this, be not specifically limited for the material of above-mentioned dielectric film 100, as long as this material is an inorganic insulating material.For example, can enumerate aluminium oxide (Al ₂O ₃), tantalum pentoxide (Ta ₂O ₅), silica (SiO ₂) etc.Preferred aluminium oxide (the Al that uses ₂O ₃).Particularly, under the situation of using aluminium oxide, be as thin as about 100nm, also can fully prevent the moisture penetration under high humidity environment even dielectric film 100 is formed.Note, when for example using such as the organic insulation of resin as the material of dielectric film, if the film of being made by this organic insulation has and the roughly the same thickness of being made by above-mentioned inorganic insulating material of dielectric film, then can not fully prevent moisture penetration.And, if increase the thickness of dielectric film in order to prevent moisture penetration, then there is the risk cause the situation that the wherein motion of piezoelectric element hindered.As mentioned above, in this embodiment, by using the dielectric film of making by inorganic insulating material 100 to cover each layer that forms piezoelectric element 300 at least, can in long-time, prevent the deterioration (destruction) of the piezoelectric layer 70 (piezoelectric element 300) that causes by moisture (humidity) reliably.

In this embodiment, on above-mentioned dielectric film 100, shown in Fig. 3 (a) and 3 (b), top electrode is drawn from the upper electrode film 80 as the single electrode of piezoelectric element 300 with lead-in wire electrode 90, and bottom electrode is drawn from lower electrode film 60 with the electrode 95 that goes between.More specifically, in above-mentioned dielectric film 100, the coupling part 200 that the first contact hole 100a will be electrically connected to each other with lead-in wire electrode 90 as wherein upper electrode film 80 and top electrode, the described first contact hole 100a is set in the zone in the face of an end of piezoelectric element 300, just in the face of being communicated with the zone of the opposite peripheral wall of sides with the ink feed path 14 of pressure generation chamber 12.And, in dielectric film 100, in this embodiment, the coupling part 250 that the second contact hole 100b will be electrically connected to each other with lead-in wire electrode 95 as wherein common lead part 65 and bottom electrode, the described second contact hole 100b be set at and pressure generation chamber 12 between the zone in the outside in corresponding zone, space in.

Therefore, top electrode with lead-in wire electrode 90 by from an end of each piezoelectric element 300 is drawn out to the end of passage formation substrate 10 by the coupling part the dielectric film 100 200 (the first contact hole 100a) near.Note,, can enumerate for example gold, aluminium alloy etc. as forming the material of above-mentioned top electrode with lead-in wire electrode 90.In this embodiment, use gold.

Simultaneously, shown in Fig. 3 (a) and 3 (b), bottom electrode, in other words, is made of gold by forming with forming the identical layer of top electrode with lead-in wire electrode 90 in this embodiment with lead-in wire electrode 95.And, in this embodiment, above-mentioned bottom electrode with the lead-in wire electrode 95 by being arranged on the second contact hole 100b in the dielectric film 100, common lead part 65 be drawn out to and pressure generation chamber 12 between the part of exterior lateral area in corresponding zone, space in, be electrically connected to common lead part 65.Particularly, common lead part 65 and bottom electrode are set at the coupling part 250 of lead-in wire between the electrode 95 in the zone in the outside of pressure generation chamber 12 ends.Note, in this embodiment, bottom electrode with lead-in wire electrode 95 along common lead part 65 be drawn out on the dielectric film 100 and top electrode with the corresponding zone, space between the lead-in wire electrode 90 (near the end of passage formation substrate 10).

At this, one or more above-mentioned bottom electrode lead-in wire electrode 95 at least can be set.Preferably, with certain interval (for example every n top electrode lead-in wire electrode 90, n represents to be not less than 1 integer) bottom electrode lead-in wire electrode 95 is set.Notice that though do not illustrate in the drawings, bottom electrode is patterned into predetermined shape with top electrode with lead-in wire electrode 90 in the following manner with lead-in wire electrode 95.Particularly, by using deposition and photoetching process to form each layer that constitutes piezoelectric element 300.After this, the metal level that is made of gold is formed on the whole surface of a side that passage forms substrate 10.Subsequently, by using this metal level of mask pattern etching of making by photoresist etc.Like this, the lead-in wire electrode is patterned.

As mentioned above, in this embodiment, bottom electrode be set at the coupling part 250 between lead-in wire electrode 95 and the common lead part 65 and pressure generation chamber 12 between the exterior lateral area in corresponding zone, space in.Therefore, can prevent reliably that bottom electrode is formed in the zone in the face of pressure generation chamber 12 with lead-in wire electrode 95, and no matter bottom electrode with the foozle of lead-in wire electrode 95 how, even for example slight fluctuation takes place with the size of lead-in wire electrode 95 in bottom electrode, even perhaps bottom electrode is offset slightly with the formation position of the electrode 95 that goes between.And bottom electrode is drawn by the further common lead part 65 from lower electrode film 60 with lead-in wire electrode 95, and the resistance value of lower electrode film 60 is reduced.Therefore, for example, be formed traditional structure with common lead electrode wherein with public electrode and compare, can prevent the voltage drop when a plurality of piezoelectric elements 300 are driven simultaneously reliably with identical patterns.Therefore, can obtain stable inkjet performance.

Particularly, in the situation of this embodiment, because the lower electrode film 60 that is included in the piezoelectric element 300 that is formed by a plurality of films is very thin, so its resistance value may be higher.But as mentioned above, common lead part 65 is integrally drawn from lower electrode film 60, and bottom electrode is further drawn from common lead part 65 with lead-in wire electrode 95.Therefore, can prevent effectively because the fluctuation of the inkjet performance that voltage drop causes.

And, in order to prevent voltage drop reliably, preferably form than common lead part 65 wideer bottom electrode lead-in wire electrodes 95.In addition, further preferably form than lower electrode film 60 thicker bottom electrode lead-in wire electrodes 95.For example, in this embodiment, bottom electrode is formed wideer and thicker than lower electrode film 60 than common lead part 65 with lead-in wire electrode 95.

Notice that the passage that is formed with piezoelectric element 300 thereon forms on the substrate 10, by using adhesive 35 join protection plates 30.Particularly, baffle 30 has piezoelectric element retaining part 31, and this piezoelectric element retaining part 31 can not hinder moving of piezoelectric element 300 in the face of guaranteeing enough spaces in the zone of piezoelectric element 300.Because piezoelectric element 300 is formed in the piezoelectric element retaining part 31, so piezoelectric element 300 is protected under the state that is subjected to external environment influence hardly.Above-mentioned piezoelectric element retaining part 31 can or can not make this space sealing.

In addition, in above-mentioned baffle 30, be provided with the fluid reservoir part 32 of at least a portion that constitutes fluid reservoir 110.In the present embodiment, this fluid reservoir part 32 forms along the width of pressure generation chamber 12, simultaneously pierce through the protection plate 30 on the thickness direction of baffle 30.And fluid reservoir part 32 is communicated with the connected component 13 that passage forms in the substrate 10 by the through hole that is arranged in the elastic membrane 50, constitutes fluid reservoir 110, and described fluid reservoir 110 will be as the common ink water cavity of each pressure generation chamber 12.Note,, can enumerate for example glass, ceramic material, metal, resin etc. as above-mentioned baffle 30.But, preferably form baffle 30 by having the material that forms substrate 10 essentially identical thermal coefficient of expansions with passage.In this embodiment, the monocrystalline substrate of using conduct and passage to form substrate 10 same materials forms baffle.

And on baffle 30, the flexible board 40 that comprises diaphragm seal 41 and fixed head 42 is incorporated into the zone corresponding to fluid reservoir part 32.At this, diaphragm seal 41 is formed by the flexible material (for example, thickness is polyphenylene sulfide (PPS) film of 6 μ m) of low rigidity, and a surface of these diaphragm seal 41 sealing fluid reservoir parts 32.And fixed head 42 is formed by the hard material (for example, thickness is the stainless steel (SUS) of 30 μ m etc.) such as metal.The zone in the face of fluid reservoir 110 of this fixed head 42 is set as opening portion 43, and it obtains by the fixed head of removing fully on its thickness direction in this zone 42.So a side of fluid reservoir 110 only seals by having flexible diaphragm seal 41.

Note, in this embodiment, drive IC 120 is installed on above-mentioned baffle 30.Though be not shown among the figure, drive IC 120, top electrode are bonded together by lead in passage forms the zone of end of substrate 10 by using by the thread connection distribution of joint with lead-in wire electrode 95 with lead-in wire electrode 90 and bottom electrode.The ink jet print head of above-mentioned this embodiment sucks ink from unshowned ink supply unit, and its from fluid reservoir 110 to nozzle bore 21 inside filling ink.Afterwards, according to driving signal, apply driving voltage to each upper electrode film 80 and the lower electrode film 60 corresponding with each pressure generation chamber 12 from drive IC 120.As a result, piezoelectric element 300 and oscillating plate are subjected to displacement.Thus, the pressure in each pressure generation chamber 12 increases, thereby from nozzle bore 21 ejection ink droplets.

(embodiment 2)

Fig. 4 is the amplification plan view according to the major part of the ink jet print head of embodiments of the invention 2.In the above embodiments 1, be described as follows structure by way of example, promptly wherein common lead part 65 and bottom electrode be set at the coupling part 250 of lead-in wire between the electrode 95 and pressure generation chamber 12 between the outside in corresponding zone, space, be described.But in this embodiment, as shown in Figure 4, common lead part 65 and bottom electrode are set in such zone with the coupling part 250A between the lead-in wire electrode 95A, this zone and piezoelectric element 300 between the outside in corresponding zone, space.

More specifically, as in the situation of the above embodiments 1, the two ends of piezoelectric element 300 in pressure generation chamber 12 orientations extend to the zone in the face of the peripheral wall of pressure generation chamber 12 from the zone in the face of pressure generation chamber 12.And, in this embodiment, the common lead part 65 of lower electrode film 60 by from lower electrode film 60 and piezoelectric element 300 between the corresponding part in space, be drawn out to as lower area, this zone and piezoelectric element 300 between the outside in corresponding zone, space.Therefore, common lead part 65 by be in and piezoelectric element 300 between the part in the outside in corresponding zone, space in coupling part 250A, be electrically connected to bottom electrode with lead-in wire electrode 95A.Utilize above-mentioned structure, can obtain the effect identical with the above embodiments 1.

And, in the situation of this embodiment, by with common lead part 65 and bottom electrode with the coupling part 250A between the lead-in wire electrode 95A be arranged on be in and piezoelectric element 300 between the zone in the outside in corresponding zone, space in, during fabrication will be without limits to the interval between piezoelectric element 300 and the coupling part 250A etc.Therefore, can arrange piezoelectric element 300 thick and fast, keep stable inkjet performance simultaneously by the distance between the constriction piezoelectric element 300.

(embodiment 3)

Fig. 5 (a) is the amplification plan view according to the major part of the ink jet print head of embodiments of the invention 3, and Fig. 5 (b) is the cutaway view along the line C-C ' among Fig. 5 (a).And Fig. 6 is the amplification plan view according to the major part of another ink jet print head of embodiments of the invention 3.In the foregoing description 1, be described as follows structure by way of example, promptly wherein common lead part 65 and is described being drawn with the identical direction of lead-in wire electrode 90 with top electrode.But, in this embodiment, shown in Fig. 5 (a) and 5 (b), common lead part 65A also by from lower electrode film 60A with draw top electrode from it and draw with the end on the opposite side of a side of lead-in wire electrode 90.

And the common lead part 65A of lower electrode film 60A is drawn out to as lower area, this zone be in and pressure generation chamber 12 between the outside in corresponding zone, space.In addition, be in end in the face of the zone of a plurality of pressure generation chambers 12 through arranging (with top electrode with lead-in wire electrode 90 opposite sides) the zone in the outside in, along the orientation of pressure generation chamber 12 common electrode layer 130 is set.Particularly, common electrode layer 130 is formed by the layer identical with forming lower electrode film 60A, and is connected with common lead part 65A by lower electrode film 60A.

Public electrode pattern 140 is provided on common electrode layer 130, its by with form bottom electrode and form with the identical layer of lead-in wire electrode 95.Notice that in this embodiment, each layer that forms piezoelectric element 300 all covered by dielectric film 100 except being laminated with the part of common electrode layer 130 and public electrode pattern 140.Utilize said structure, can prevent voltage drop more reliably, and can obtain more stable inkjet performance.

Notice that this embodiment is not limited to said structure.For example, as shown in Figure 6, with the corresponding part of common lead part 65A of the second public electrode pattern 140A in, extension 140a can be set, this extension 140a extend to piezoelectric element 300 between the exterior lateral area in corresponding zone, space.Therefore, can prevent voltage drop more reliably.

And in this embodiment, what adopted is following structure, and wherein piezoelectric element 300 is in the zone that all extends to perpendicular to the two ends on the direction of the orientation of pressure generation chamber 12 in the face of the peripheral wall of pressure generation chamber 12.But, need not many speeches, this structure is not limited to above-mentioned structure.Though be not shown among the figure, piezoelectric element in the zone that can be arranged on corresponding to the other end on the side of public electrode pattern in the face of pressure generation chamber.Therefore, extend in the face of the situation in the zone of the peripheral wall of pressure generation chamber with the described other end of piezoelectric element wherein and to compare, can increase with respect to passage and form whole surface on the side of substrate, the ratio of public electrode pattern area occupied.As a result, can prevent voltage drop more reliably.

(embodiment 4)

Fig. 7 is the amplification plan view according to the major part of the ink jet print head of embodiments of the invention 4.In the above embodiments 3, illustrate that by way of example wherein common electrode layer 130 and public electrode pattern 140 are described by the structure that common lead part 65A is electrically connected to lower electrode film 60A.But in this embodiment, as shown in Figure 7, lower electrode film 60B extends continuously from the zone in the face of a plurality of pressure generation chambers 12 through arranging, and arrives public electrode pattern 140B.Particularly, lower electrode film 60B is from the zone in the face of a plurality of pressure generation chambers 12 through arranging, and extends to the zone in the face of the feed path 14 through arranging of (dielectric film 55) on the surface that passage forms substrate 10.And, in part, public electrode pattern 140B is set along the orientation of pressure generation chamber 12 on the surface of lower electrode film 60, in the face of feed path 14 through arranging.Utilize said structure, can guarantee the rigidity of oscillating plate in the zone of the end of facing pressure generation chamber 12 fully, prevent voltage drop simultaneously more reliably.

(embodiment 5)

Fig. 8 is the amplification plan view according to the major part of the ink jet print head of embodiments of the invention 5.In the above embodiments 1, explanation has the bottom electrode lead-in wire electrode 95 of single layer structure by way of example, and is described.But in this embodiment, as shown in Figure 8, bottom electrode is formed by adhesion layer 95a and metal level 95b with lead-in wire electrode 95A, and described adhesion layer 95a is made by adhesiving metal, and described metal level 95b makes and is arranged on the adhesion layer 95a by metal material.And adhesion layer 95a extends the end that arrives lower electrode film 60, and bottom electrode is electrically connected to each other by the adhesion layer 95a that extends with lead-in wire electrode 95A and lower electrode film 60.

More specifically, bottom electrode is formed in the part of wherein stacked adhesion layer 95a and metal level 95b with lead-in wire electrode 95A.And, be included in bottom electrode with the metal level 95b among the lead-in wire electrode 95A in the end of piezoelectric element 300 sides is placed in as lower area, this zone be in and pressure generation chamber 12 between the outside in corresponding zone, space.Therefore, bottom electrode is electrically connected to lower electrode film 60 with lead-in wire electrode 95A by adhesion layer 95a.And adhesion layer 95a extends the base portion that arrives common lead part 65 separately from the base portion in the face of the zone of metal level 95b.Therefore, adhesion layer 95a plays the effect that metal level 95b is attached to dielectric film 100 on dielectric film 100.And, adhesion layer 95a play bottom electrode with the join domain between lead-in wire electrode 95A and the lower electrode film 60 in (in coupling part 250) corresponding to the second contact hole 100b, the effect that the common lead part 65 of metal level 95b and lower electrode film 60 is attached to one another and is electrically connected.

Note,, for example can enumerate titanium-tungsten, nichrome etc. as the adhesiving metal of the material that forms adhesion layer 95a.Be formed on the material of the metal level 95b on the adhesion layer 95a as formation, for example can enumerate aluminium alloy, gold etc.And the thickness of adhesion layer 95a for example is that about 0.1 μ m is to 0.3 μ m.The thickness of adhesion layer 95a preferably is equal to or less than the thickness of lower electrode film 60, and more preferably is set as the thickness less than lower electrode film 60.This is in order to prevent effectively owing to increasing the rigidity of oscillating plate in the face of formation adhesion layer 95a in the zone of pressure generation chamber 12.For example, in this embodiment, the thickness of lower electrode film 60 is set as about 0.2 μ m, and the thickness of adhesion layer 95a is set as about 0.1 μ m.Simultaneously, the thickness of metal level 95b for example is about 1.0～3.0 μ m, and is preferably greater than the thickness of lower electrode film 60.This is in order to reduce the resistance value of lower electrode film 60.For example, in this embodiment, the thickness of metal level 95b is set as about 1.2 μ m.

As mentioned above, in this embodiment, only bottom electrode is extended the bottom of common lead part 65 with the adhesion layer 95a of lead-in wire electrode 95A.Therefore, for example compare, can further reduce the resistance value in the coupling part 250 between bottom electrode usefulness lead-in wire electrode 95A and the lower electrode film 60 with the structure of the above embodiments 1.

Note, in the above-described embodiment, for example understand following structure, wherein only bottom electrode is extended the bottom of common lead part 65 with the adhesion layer 95a of the electrode 95A that goes between.But, need not many speeches, this structure is not limited to above-mentioned structure.For example, bottom electrode with the adhesion layer of lead-in wire electrode can from common lead partly extend to and the piezoelectric activity of piezoelectric element part between corresponding zone, space.In above-mentioned structure, because adhesion layer is thinner relatively, even adhesion layer is because foozle is projected in the zone in the face of pressure generation chamber, the rigidity of oscillating plate also changes hardly.And, metal level be set at be in and pressure generation chamber between the exterior lateral area in corresponding zone, space in.Therefore, no matter the foozle of metal level how, even for example slight fluctuation appears in the size of metal level, even perhaps slight shift takes place in the formation position of metal level, metal level can not be formed in the zone in the face of pressure generation chamber yet.Therefore, even the foozle of bottom electrode occur, also can prevent the fluctuation of inkjet performance reliably with the lead-in wire electrode.

(embodiment 6)

Fig. 9 is the decomposition diagram according to the ink jet print head of embodiment 6.Figure 10 (a) is the vertical view according to the ink jet print head of embodiment 6, and Figure 10 (b) is the cutaway view along the line D-D ' among Figure 10 (a).Figure 11 (a) is the vertical view according to the amplification of the major part of the ink jet print head of embodiment 6, and Figure 11 (b) is the cutaway view along the line E-E ' among Figure 11 (a).

In this embodiment, shown in Fig. 9-11, lower electrode film 60C is arranged on the zone of facing a plurality of pressure generation chambers 12 through arranging continuously.More specifically, lower electrode film 60C is arranged on the whole zone of facing the zone of pressure generation chamber 12 and facing the partition wall 11 of both sides in the orientation of pressure generation chamber 12 continuously by the orientation along pressure generation chamber 12.And, lower electrode film 60C in the zone that is placed in respectively perpendicular to the two ends on the direction of the orientation of pressure generation chamber 12 in the face of pressure generation chamber 12.In addition, bottom electrode is connected to the end of above-mentioned lower electrode film 60C with lead-in wire electrode 95B.In this embodiment, bottom electrode has double-layer structure with lead-in wire electrode 95B, more specifically, is formed by adhesion layer 95a and metal level 95b, described adhesion layer 95a is made by adhesiving metal, and described metal level 95b makes and is arranged on the adhesion layer 95a by metal material.

And, bottom electrode with lead-in wire electrode 95B be set at be in and pressure generation chamber 12 between the exterior lateral area in corresponding zone, space in.In addition, only be to be included in bottom electrode to be extended the end that arrives lower electrode film 60C with the adhesion layer 95a among the lead-in wire electrode 95B.And bottom electrode is electrically connected to each other by the adhesion layer 95a that extends with lead-in wire electrode 95B and lower electrode film 60C.Except above-mentioned these, embodiment 6 is identical with embodiment 1.

In addition, equally in this embodiment, cover with dielectric film as the area of the pattern in the zone of arranging piezoelectric element 300.On this dielectric film 100, top electrode is drawn with lead-in wire electrode 90A, and described top electrode is electrically connected with the upper electrode film 80 of piezoelectric element 300 by the first contact hole 100a with lead-in wire electrode 90A.Simultaneously, in dielectric film 100, the coupling part 250 that the second contact hole 100b will be electrically connected to each other with lead-in wire electrode 95B as wherein lower electrode film 60C and bottom electrode, the described second contact hole 100b be set at pressure generation chamber 12 between corresponding zone, space in.For example, in this embodiment, the second contact hole 100b be set at dielectric film 100 in the orientation of pressure generation chamber 12 side, and pressure generation chamber 12 between corresponding zone, space in the end in, promptly be arranged on top electrode with the lead-in wire end of electrode 90A on the side that it is drawn.

Shown in Figure 10 (a) and 10 (b), above-mentioned top electrode is formed by adhesion layer 90a and metal level 90b with lead-in wire electrode 90A, described adhesion layer 90a is made by the adhesiving metal such as titanium-tungsten and nichrome, and quilt utmost point film 80 from power on is drawn out on the dielectric film 100, described metal level 90b is made by aluminium alloy, gold etc., and is arranged on the adhesion layer 90a.Notice that top electrode is the relatively thin layer that is used for metal level 90b is attached to dielectric film 100 grades with the adhesion layer 90a of lead-in wire electrode 90A.

Simultaneously, in this embodiment, bottom electrode has and the above-mentioned top electrode identical structure of lead-in wire electrode 90A with lead-in wire electrode 95B.More specifically, shown in Figure 11 (a) and 11 (b), bottom electrode is formed by adhesion layer 95a and metal level 95b with lead-in wire electrode 95B, and described adhesion layer 95a is made by adhesiving metal, and be electrically connected to lower electrode film 60C, described metal level 95b is arranged on the adhesion layer 95a.Particularly, adhesion layer 95a is by forming with the identical layer of the adhesion layer 90a of lead-in wire electrode 90A with top electrode, and metal level 95b by with top electrode with identical layer the forming of the metal level 90b of lead-in wire electrode 90A.

And bottom electrode is above-mentioned adhesion layer 95a and the stacked part of metal level 95b with lead-in wire electrode 95B, described bottom electrode with the electrode 95B that goes between be placed in be in and pressure generation chamber 12 between the exterior lateral area in corresponding zone, space in.And, in this embodiment, bottom electrode with lead-in wire electrode 95B be extended on the dielectric film 100 and top electrode with near the corresponding zone, space (passage forms the end of substrate 10) between the lead-in wire electrode 90A.In this embodiment, be included in above-mentioned bottom electrode and be extended the end that arrives lower electrode film 60C with the adhesion layer 95a among the lead-in wire electrode 95B.Adhesion layer (extension) 95a that extends is electrically connected to lower electrode film 60C by the second contact hole 100b (coupling part 250) in the dielectric film 100.Therefore, lower electrode film 60C and bottom electrode are electrically connected to each other with lead-in wire electrode 95B.Notice that in this embodiment, in the zone corresponding to the space between the pressure generation chamber 12, above-mentioned uses the width of the extended adhesion layer 95a of lead-in wire electrode 95B less than the width of bottom electrode with lead-in wire electrode 95B from bottom electrode.

At this, be included in bottom electrode with the thickness of the adhesion layer 95a among the lead-in wire electrode 95B for example for about 0.1 μ m to 0.3 μ m, and preferably be equal to or less than the thickness of lower electrode film 60C, be more preferably less than the thickness of lower electrode film 60C.This is in order to prevent effectively owing to increasing the rigidity of oscillating plate in the face of formation adhesion layer 95a in the zone of pressure generation chamber 12.This will be described in detail later.For example, in this embodiment, the thickness of lower electrode film 60C is set as about 0.2 μ m, and the thickness of adhesion layer 95a is set as about 0.1 μ m.Simultaneously, the thickness of metal level 95b for example is about 1.0～3.0 μ m, and is preferably greater than the thickness of lower electrode film 60C.This is in order to reduce the resistance value of lower electrode film 60C.For example, in this embodiment, the thickness of metal level 95b is set as about 1.2 μ m.

Note, in this embodiment,,, bottom electrode is patterned to predetermined shape together with top electrode with lead-in wire electrode 90A with lead-in wire electrode 95B with following mode though be not shown among the figure.Particularly, by using deposition and photoetching method to form each layer that constitutes piezoelectric element 300.After this, the ground floor and the second layer are laminated on the whole surface of passage formation substrate 10 1 sides.Subsequently, by after using the mask pattern etching second layer of making by photoresist etc., the etching ground floor.So the lead-in wire electrode is patterned.

As mentioned above, in the ink jet print head of this embodiment, bottom electrode with lead-in wire electrode 95B be set at be in and pressure generation chamber 12 between the exterior lateral area in corresponding zone, space in.In addition, be included in bottom electrode and be extended arrival lower electrode film 60C with the adhesion layer 95a among the lead-in wire electrode 95B.And bottom electrode is electrically connected to each other by the adhesion layer 95a that extends with lead-in wire electrode 95B and lower electrode film 60C.Therefore, can obtain stable inkjet performance.

More specifically, in this embodiment, be included in bottom electrode and be extended the end that arrives lower electrode film 60C with the adhesion layer 95a among the lead-in wire electrode 95B.Therefore, obtain the structure that bottom electrode wherein is electrically connected to each other with lead-in wire electrode 95B and lower electrode film 60C.Therefore, even adhesion layer 95a is because foozle is projected in the zone in the face of pressure generation chamber 12, the rigidity of oscillating plate also changes hardly, because adhesion layer 95a is thinner relatively.And, bottom electrode with lead-in wire electrode 95B be set at be in and pressure generation chamber 12 between the exterior lateral area in corresponding zone, space in.Therefore, no matter the foozle of metal level 95b how, even for example slight fluctuation appears in the size of metal level 95b, even perhaps slight shift takes place in the formation position of metal level 95b, metal level 95b can not be formed in the zone in the face of pressure generation chamber yet.Therefore, even the foozle of bottom electrode occur, also can prevent the fluctuation of inkjet performance reliably with lead-in wire electrode 95B.

And, in this embodiment, by bottom electrode is connected to lower electrode film 60C with lead-in wire electrode 95B, the voltage drop in the time of can preventing to drive simultaneously a plurality of piezoelectric element 300 reliably.More specifically, in the situation of this embodiment, because the lower electrode film 60C that is included in the piezoelectric element 300 that is formed by film is very thin, so that its resistance value may become is higher.But, as mentioned above,, reduced the resistance value of lower electrode film 60C by bottom electrode is connected to lower electrode film 60C with lead-in wire electrode 95B.Therefore, the voltage drop in the time of can preventing to drive at the same time a plurality of piezoelectric element 300 reliably.Therefore, can also prevent reliably because the fluctuation of the inkjet performance that voltage drop causes.

(embodiment 7)

Figure 12 (a) is the amplification plan view according to the major part of the ink jet print head of embodiments of the invention 7, and Figure 12 (b) is the cutaway view along the line G-G ' among Figure 12 (a).In the above embodiments 6, illustrate by way of example that bottom electrode wherein is set at lead-in wire electrode 95B and pressure generation chamber 12 between the structure in the outside in corresponding zone, space, and be described.Equally, in this embodiment, shown in Figure 12 (a) and Figure 12 (b), bottom electrode be set at lead-in wire electrode 95D and piezoelectric element 300 between the exterior lateral area in corresponding zone, space in.Utilize said structure, can obtain the effect identical with the above embodiments 1.

And, in the situation of this embodiment, by bottom electrode is arranged on lead-in wire electrode 95D and piezoelectric element 300 between the exterior lateral area in corresponding zone, space in, during fabrication will be with the interval between the lead-in wire electrode 95D etc. without limits to piezoelectric element 300 and bottom electrode.Therefore, can arrange piezoelectric element 300 thick and fast, keep stable inkjet performance simultaneously by the distance between the constriction piezoelectric element 300.

In the above embodiments 6, illustrate by way of example comprising being extended the structure of the end that arrives lower electrode film 60C with the adhesion layer 95a among the lead-in wire electrode 95B, and be described at bottom electrode.Simultaneously, in this embodiment, shown in Figure 12 (a) and 12 (b), public electrode pattern 140C is arranged on as in the lower area by the orientation along pressure generation chamber 12, and this zone is in outside pressure generation chamber 12 and the end opposite side of bottom electrode usefulness lead-in wire electrode 95D.Therefore, be included in bottom electrode and be extended arrival public electrode pattern 140C with the adhesion layer 95a among the lead-in wire electrode 95D.

At this, in this embodiment, public electrode pattern 140C is formed by the first public electrode pattern 141 and the second public electrode pattern 142, the described first public electrode pattern 141 has and the bottom electrode identical structure of lead-in wire electrode 95D, more specifically, made by the layer identical with forming adhesion layer 95a, the described second public electrode pattern 142 is made by the layer identical with forming metal level 95b.Notice that in this embodiment, each layer that forms piezoelectric element 300 all covered by dielectric film 100 except being laminated with the part of the first public electrode pattern 141 and the second public electrode pattern 142.

Be extended the above-mentioned public electrode pattern 140C of arrival from bottom electrode with the extended adhesion layer 95a of lead-in wire electrode 95D.Particularly, bottom electrode with lead-in wire electrode 95D and public electrode pattern 140C by being electrically connected to each other with the extended adhesion layer 95a of electrode 95D that goes between from bottom electrode.And, be connected to lower electrode film 60C with lead-in wire electrode 95D extended adhesion layer 95a by the second contact hole 100b from bottom electrode, the described second contact hole 100b is in the dielectric film 100, locate with the two ends in the orientation of pressure generation chamber 12 in corresponding zone, space between the piezoelectric element 300.Utilize said structure, can further reduce the resistance value of bottom electrode, and can prevent voltage drop more reliably.

In addition, in this embodiment, adhesion layer 95a is set in each zone of the partition wall 11 of facing a plurality of pressure generation chambers 12 through arranging.Each adhesion layer 95a is set to have identical pattern form in the zone of the partition wall of facing pressure generation chamber 12.And, among a plurality of adhesion layer 95a one be from bottom electrode with the extended adhesion layer 95a of lead-in wire electrode 95B, and remaining is the empty electrode 150 that is formed by adhesion layer 95a only.Utilize said structure, the vibration characteristics of the oscillating plate in each piezoelectric element 300 homogeneous that becomes.Therefore, can prevent the fluctuation of inkjet performance reliably.

(other embodiment)

Though described embodiments of the invention 1-8 above, need not many speeches, the invention is not restricted to the embodiments described 1-8.For example, in the above embodiments 1-8, illustrate that by way of example each layer that wherein forms piezoelectric element covered by dielectric film and top electrode is drawn out to the lip-deep structure of dielectric film with lead-in wire electrode and bottom electrode with the lead-in wire electrode, and be described.But, need not many speeches, the invention is not restricted to above-mentioned structure, but can have following structure, the top electrode that wherein is connected to each piezoelectric element is covered by dielectric film with the lead-in wire electrode with the bottom electrode that is connected to lower electrode film with the electrode that goes between, except top electrode is used the coupling part that goes between between electrode and the outside wiring with lead-in wire electrode and bottom electrode.

Note, in said structure, preferably use aluminium alloy as form top electrode with and bottom electrode with the material of the metal layer of electrodes that goes between.The metal level of being made by aluminium alloy has more smooth surface.Therefore, can improve dielectric film and the adhesion of lead-in wire between the electrode.And, if same material (for example aluminium oxide) is used as insulating film material, then can further improve the adhesion between dielectric film and the lead-in wire electrode.

Particularly, the structure of each among the foregoing description 5-7 is set under top electrode usefulness and the situation of bottom electrode usefulness lead-in wire electrode with the structure of aforesaid dielectric film covering therein, for example can adopt following structure.Particularly, in this structure, by will and pressure generation chamber between corresponding zone, space in lower electrode film be drawn out to bottom electrode with the lead-in wire electrode at top electrode with the end of lead-in wire electrode one side, the common lead part is set.In addition, adhesion layer extends in the common lead part with the lead-in wire electrode from bottom electrode.And bottom electrode is electrically connected to each other by the adhesion layer on the common lead part with lead-in wire electrode and lower electrode film.Utilize said structure, can fully guarantee bottom electrode and the bottom electrode thickness of lead-in wire electrode in this part connected to one another.And, can prevent voltage drop more reliably.

And, in the above embodiments 1-8, illustrate that by way of example wherein the two ends of lower electrode film in the orientation of pressure generation chamber are set in the face of the structure in the zone of pressure generation chamber, and be described.But, need not many speeches, the invention is not restricted to said structure, but can have following structure, wherein lower electrode film extends to from the zone in the face of a plurality of pressure generation chambers through arranging in the face of being positioned at the zone that passage forms a lip-deep ink feed path through arranging of substrate.Utilize said structure, can fully guarantee the rigidity of oscillating plate in the zone of the end that is arranged in ink feed path one side of facing pressure generation chamber.

In addition, in the above embodiments 1-8, illustrate that by way of example the two ends of piezoelectric element wherein extend to the structure in the face of the zone of the peripheral wall of pressure generation chamber, and be described.But, need not many speeches, the invention is not restricted to said structure, but can for example have following structure, wherein each piezoelectric element is in the end of connected component side is set at zone in the face of pressure generation chamber.Utilize said structure, can increase with respect to the whole surface on the side of passage formation substrate, the ratio of public electrode pattern area occupied.Therefore, can prevent voltage drop more reliably.

The ink jet print head of each in the foregoing description constitutes the part of the head unit that comprises the ink channel that is communicated with print cartridge etc., and is installed in the ink jet recording device.Figure 13 shows the schematic diagram of an example of ink jet recording device.As shown in figure 13, box 2A and the 2B that is included in the ink supply unit is removably disposed among the head unit 1A and 1B with ink jet print head.The carriage 3 that head unit 1A and 1B are installed on it is set on the bracket axle 5 that is installed to equipment body 4 in the mode that can move vertically.For example, these head unit 1A and 1B are respectively the head unit of spraying black ink composition and color inks composition.The driving force of drive motors 6 is by a plurality of gears that do not illustrate and be with 7 to be delivered to carriage 3 synchronously.Therefore, the carriage 3 that head unit 1A and 1B are installed on it moves along bracket axle 5.Simultaneously, in equipment body 4, be provided with cylinder 8 along bracket axle 5, and as transmitting on cylinder 8 such as the recording medium of the scraps of paper and by the documentary film S that roller etc. infeeds that infeeds that does not illustrate.

And, as the example of fluid jetting head of the present invention ink jet print head is described.But the basic structure of fluid jetting head is not limited to above-mentioned structure.The invention is intended to broadly be applied to general fluid jetting head, and need not many speeches, can also be applied to spray the fluid jetting head of the liquid of different sub-inks.As other fluid jetting head, for example can enumerate: be used for various record heads such as the image recorder of printer; Be used to make the pigment shower nozzle of the colour filtering of LCD etc.; Be used to form the electrode material shower nozzle of the electrode of OLED display, FED (Field Emission Display) etc.; Be used to biological organic substance shower nozzle of making biochip etc.

Claims (17)

1. fluid jetting head comprises:

Passage forms substrate, wherein is formed with a plurality of pressure generation chambers that are communicated with the nozzle bore of atomizing of liquids;

Piezoelectric element, it is set at described passage and forms above substrate one side in the zone of described pressure generation chamber and oscillating plate is placed in described piezoelectric element and described passage forms between the substrate, and each in the described piezoelectric element comprises bottom electrode, piezoelectric layer and top electrode;

Top electrode lead-in wire electrode, it is drawn from described top electrode; With

Bottom electrode lead-in wire electrode, it is drawn from described bottom electrode,

Wherein, described bottom electrode is arranged on continuously in the face of the public electrode in the zone of a plurality of described pressure generation chambers through arranging,

End at least one side on the direction vertical with orientation described pressure generation chamber described bottom electrode is arranged in the zone in the face of described pressure generation chamber,

Described bottom electrode has the common lead part, described common lead part from and described pressure generation chamber between corresponding zone, space an end be drawn out to and adjacent described pressure generation chamber between the outside in corresponding zone, space,

Described bottom electrode is electrically connected to the described common lead part of described bottom electrode with the lead-in wire electrode, and

Described bottom electrode with the coupling part between lead-in wire electrode and the described common lead part and described pressure generation chamber between the exterior lateral area in corresponding zone, space in.

2. fluid jetting head as claimed in claim 1, wherein

End at least one side on the direction vertical with orientation described pressure generation chamber described piezoelectric element extends to the zone right with the peripheral wall of described pressure generation chamber from the zone in the face of described pressure generation chamber, and

Described bottom electrode with the coupling part between the described common lead part on that side of a described end of lead-in wire electrode and described piezoelectric element and described piezoelectric element between the exterior lateral area in corresponding zone, space in.

3. fluid jetting head as claimed in claim 1, wherein, the public electrode pattern that is connected to described bottom electrode is arranged on as in the lower area along the orientation of described pressure generation chamber, that is: be in the face of in the zone of a plurality of described pressure generation chambers through arranging with the outside of described bottom electrode with lead-in wire electrode opposite end.

4. fluid jetting head as claimed in claim 3, wherein, described common lead part is also drawn from the end of the opposite side of described bottom electrode arrives described public electrode pattern.

5. fluid jetting head as claimed in claim 3, wherein, described bottom electrode is provided with continuously, to arrive described public electrode pattern from the zone in the face of a plurality of described pressure generation chambers through arranging.

6. fluid jetting head as claimed in claim 3, wherein, described piezoelectric element with the corresponding side of described public electrode pattern on the other end be arranged in zone in the face of described pressure generation chamber.

7. fluid jetting head as claimed in claim 1, wherein

Described bottom electrode is formed by adhesion layer and metal level with the lead-in wire electrode, and described adhesion layer is made by adhesiving metal, and described metal level is made and is arranged on the described adhesion layer by metal material, and

Described adhesion layer extends the described end on the described side that arrives described bottom electrode, and described bottom electrode is electrically connected to each other by the described adhesion layer that extends with lead-in wire electrode and described bottom electrode.

8. fluid jetting head as claimed in claim 1, wherein, at least each layer that forms described piezoelectric element used the described coupling part that goes between between electrode and the described common lead part except described bottom electrode, the dielectric film of all being made by inorganic insulating material covers, and described bottom electrode is drawn out on the described dielectric film with the lead-in wire electrode.

9. fluid jetting head comprises:

Passage forms substrate, wherein is formed with a plurality of pressure generation chambers that are communicated with the nozzle bore of atomizing of liquids;

Piezoelectric element, it is set at described passage and forms above substrate one side in the zone of described pressure generation chamber and oscillating plate is placed in described piezoelectric element and described passage forms between the substrate, and each in the described piezoelectric element comprises bottom electrode, piezoelectric layer and top electrode;

Top electrode lead-in wire electrode, it is connected to described top electrode; With

Bottom electrode lead-in wire electrode, it is connected to described bottom electrode,

Wherein, described bottom electrode is arranged on continuously in the face of the public electrode in the zone of a plurality of described pressure generation chambers through arranging,

End at least one side on the direction vertical with orientation described pressure generation chamber described bottom electrode is arranged in described zone in the face of pressure generation chamber,

Described bottom electrode is formed by adhesion layer and metal level with the lead-in wire electrode, and described adhesion layer is made by adhesiving metal, and described metal level is made and is arranged on by metal material on the described adhesion layer,

Described bottom electrode with the lead-in wire electrode and described pressure generation chamber between the exterior lateral area in corresponding zone, space in, and

The described bottom electrode of described formation extends described end on the described side that arrives described bottom electrode with the adhesion layer of lead-in wire electrode, and described bottom electrode is electrically connected to each other with lead-in wire electrode and the described bottom electrode described adhesion layer by extension.

10. the described fluid jetting head of claim 9, wherein, the thickness of described adhesion layer is equal to or less than the thickness of described bottom electrode, and described metal layer thickness is greater than the thickness of described bottom electrode.

11. fluid jetting head as claimed in claim 9, wherein, the public electrode pattern that is connected to described bottom electrode is arranged on as in the lower area along the orientation of described pressure generation chamber, that is: be in the face of in the zone of a plurality of described pressure generation chambers through arranging with the outside of described bottom electrode with lead-in wire electrode opposite end.

12. fluid jetting head as claimed in claim 11, wherein, described adhesion layer extends the described public electrode pattern of arrival from described bottom electrode with the lead-in wire electrode, and described bottom electrode is connected to each other by the described adhesion layer that extends with lead-in wire electrode and described public electrode pattern.

13. fluid jetting head as claimed in claim 9, wherein, described adhesion layer is arranged in the zone of facing with the partition wall of a plurality of described pressure generation chambers through arranging each, and each adhesion layer at least with zone that the partition wall of described pressure generation chamber is faced in have identical pattern.

14. fluid jetting head as claimed in claim 13 wherein, extends with the lead-in wire electrode from described bottom electrode one of in described a plurality of adhesion layers, and remaining be the empty electrode that only forms by described adhesion layer.

15. fluid jetting head as claimed in claim 9, wherein, described bottom electrode has the common lead part, described common lead part is drawn out to described bottom electrode with the lead-in wire electrode by the described end from the described side of described bottom electrode, and described bottom electrode is connected to each other by being arranged on the described adhesion layer of described common lead on partly with lead-in wire electrode and described bottom electrode.

16. fluid jetting head as claimed in claim 9, wherein, each layer that forms described piezoelectric element at least is except the coupling part between described bottom electrode and the described adhesion layer, and the dielectric film of all being made by inorganic insulating material covers.

17. a liquid injection device comprises as any one described fluid jetting head among the claim 1-16.

Images