DE102004053875A1 - Fluid injector and method of manufacturing the same - Google Patents

Abstract

A fluid injector and method of manufacturing the same. The fluid injector comprises a base, a first through hole, a fluid actuator, a passivation layer, and a hydrophobic layer. The base includes a chamber and a surface. The first through hole communicates with the chamber, and is disposed in the base. The fluid actuator is disposed on the surface near the first through hole, and is located outside the chamber. The passivation layer is disposed on the surface. The hydrophobic layer defines a second through hole, and is disposed on the passivation layer outside the chamber. The second through hole communicates with the first through hole.

Description

Territory of invention

The The present invention relates to a fluid injector device or a fluid injection device and a process for their preparation; in particular the invention a fluid injector with a higher efficiency and a longer life.

description of the prior art

Usually become fluid injectors in inkjet printers, fuel injectors and other devices. In the currently known and inkjet printers used is the injection due to heat driven bubble due to its simplicity and the comparatively low cost has been the most successful.

The 1 shows a conventional monolithic fluid injector 1 as disclosed in U.S. Patent No. 6,102,530. A structural layer 12 is on a silicon substrate 10 educated. A fluid chamber 14 is between the silicon substrate 10 and the structural layer 12 designed to be a fluid 26 take. A first heating device 20 and a second heater 22 are on the structural layer 12 intended. The first heating device 20 generated in the chamber 14 a first bubble 30 and the second heater 22 generated in the chamber 14 a second bubble 32 to the fluid 26 out of the chamber 14 eject.

The monolithic fluid injector 1 comprises a virtual valve and is arranged in a high-density arrangement. In addition, the monolithic fluid injector provides 1 for low mixing and low heat loss. In addition, there is no need to connect an additional nozzle plate to the monolithic fluid injector. Consequently, the cost of the monolithic fluid injector 1 lower.

In the conventional monolithic fluid injector 1 however, there is the structural layer 12 mainly of low voltage silicon oxide. During manufacture, the thickness of the structural layer becomes 12 maintained within a predetermined range; therefore, the life of the entire structure of the conventional monolithic fluid injector is 1 also limited. Because the thickness of the structural layer 12 is insufficient, moreover, the direction of the injected fluid is not consistent. In addition, after a micro-fluid droplet leaves the orifice, the fluid flows back into the fluid chamber and spreads to the surface of the fluid injector device, causing some overflow and adversely affecting the next injection.

Summary the invention

task It is the object of the present invention to overcome the disadvantages of the aforementioned At least partially fix fluid injector to a fluid injector to provide better efficiency and longer life. These and other objects are achieved according to the present invention by a fluid injector or a fluid injection device with the features of claim 1 and by a method of its or their preparation according to claim 9 solved. Further advantageous embodiments are the subject of the referenced Dependent claims.

Of the Fluid injector according to the present invention includes a base, a first through-hole, a fluid actuator, a passivation layer and an electrodeposited layer. The Base includes a chamber and a surface. The first through hole communicates with the chamber and is provided in the base. The fluid actuator is on the surface near the first through hole provided and is located outside the chamber of the base. The passivation layer is provided on the surface. The galvanically formed layer defines a second through-bore fixed and is provided on the passivation layer outside the chamber. The second through-hole communicates with the first through-hole.

at a preferred embodiment is the diameter of one end of the second hole that is with the first through hole communicates, much larger than that of the other end of the second through-hole.

Of the Fluid actuator includes a thermal bubble generator or a piezoelectric thin film actuator. The fluid actuator is preferably a thermal bubble generator, which consists of a resistance layer.

at a preferred embodiment is a patterned conductive Layer formed, which covers the structural layer and with the fluid actuator connects to as a signal transmission circuit to act.

It It should be noted that the contact or wetting angle between the electrodeposited layer and water is about 90 ° or greater and that the electrodeposited layer is preferably an epoxy resin, Glycidyl methacrylate, acrylic resin, acrylate or methacrylate of a Novolac epoxy resin, polysulfone, polyphenylenes, polyethersulfone, Polyamide, polyamide-imide, polyarylene-ether, polyphenylene-sulfide, pholyarene-ether-ketone, Phenoxy resin, polycarbonate, polyetherimide, polyquinoxaline, polyquinoline, Polybenzimidazole, polybenzoxazole, polybenzothazole or polyoxadiazole is.

According to the present The invention also provides a method of manufacturing a fluid injector. The method comprises the following steps. A substrate with a first surface and a second surface will be provided. A patterned sacrificial layer or temporary layer will be on the first surface formed of the substrate. A patterned structure layer becomes on the first surface formed of the substrate and covers the patterned sacrificial layer. A fluid actuator is provided on the structural layer, wherein the fluid actuator is outside the chamber is located. A patterned conductive layer is formed that covers the structure layer and as a signal transmission circuit acts. A passivation layer becomes on the passivation layer formed and covers the fluid actuator. An electroplated Layer is formed on the passivation layer. A fluid channel is in the second surface opposite to the substrate the first surface trained and the sacrificial layer is exposed. The sacrificial shift becomes removed to form a chamber.

It It should be noted that the fluid actuator of the galvanic is formed layer formed and that the galvanically formed Layer by spin coating or spin coating or by Rolling up the passivation layer is piled up and that the structural layer is a silicon oxynitride or silicon nitride layer is.

According to one preferred embodiment the procedure as well the step that a second through hole in the galvanically formed Layer is formed. The second through-hole communicates with the first through hole.

According to one another preferred embodiment includes the method as well the following steps. A second through hole is made by Gray scale lithography so formed in the electrodeposited layer that the diameter the upper end of the second bore is substantially larger as that of the lower end of the second through-hole. Then be the passivation layer and the structural layer are sequentially etched to to form a first through-hole. The first through hole communicates with the chamber and the second through-bore.

The The present invention overcomes the prior art an improvement that on the surface of the structural layer of the Fluid injector device formed a galvanically formed layer becomes. The electrodeposited layer may be the structural layer increase the fluid injector device and the Grenzflächencharakterisik the surface improve the fluid injector device. Because the length of the Injection path of the fluid substantially to the additional Thickness of the electrodeposited layer can be increased, can also Direction of the injected fluid be more consistent.

LIST OF FIGURES

The The present invention can be understood by reading the following detailed Description in common with the embodiments and with reference on the attached Drawings are better understood, wherein:

1 Fig. 12 is a schematic view of a conventional monolithic fluid injector;

2 Fig. 12 is a schematic view of a fluid injector as disclosed in accordance with a first embodiment of this invention;

3a - 3e are schematic views showing a method of manufacturing the fluid injector according to the 2 show only a part P1 is shown;

4 Fig. 12 is a schematic view of a fluid injector according to a second embodiment of this invention; and

5a - 5c are schematic views illustrating the steps of grayscale lithography.

Full Description of the invention

First embodiment

The 2 shows a fluid injector 100 according to a first embodiment of this invention. In this embodiment, the fluid injector includes 100 One Base 110 , a first through hole 114 , a fluid actuator 120 , a passivation layer 130 and a galvanically formed layer 140 ,

The base 110 includes a silicon substrate 111 and a structural layer 112 , The structural layer 112 is on the silicon substrate 111 intended. A chamber 113 is between the silicon substrate 111 and the structural layer 112 educated. The first through hole 114 is in the structural layer 112 trained and communicates with the chamber 113 ,

The fluid actuator 120 is on a surface 1122 the structural layer 112 provided, as in the 3a shown. The fluid actuator 120 includes a thermal bubble generator or a piezoelectric thin film actuator. The fluid actuator is preferably a thermal bubble generator consisting of a resistive layer. The thermal bubble generator is located near the first through hole 114 and outside the chamber 113 the base 110 , In this embodiment, the thermal bubble generating device includes 120 a first heating device 121 and a second heater 122 , Just like the ones in the 1 shown heaters generates the first heater 120 in the chamber 113 a first bubble and generates the second heater 122 in the chamber 113 a second bubble to remove fluid from the chamber 113 eject.

The passivation layer 130 (For example, silicon nitride) is on the surface 1122 the structural layer 112 provided and includes a fifth through hole 131 , The electroplated layer 140 includes a second through-hole 141 and is on the passivation layer 130 outside the chamber 113 intended. The second through hole 141 communicates with the first through hole 114 over the fifth through hole 131 ,

It should be noted that it is in the electrodeposited layer 140 may be a material having a negative photosensitivity, for example, epoxy resin, glycidyl methacrylate, acrylic resin, acrylate or methacrylate of a novolak epoxy resin, polysulfone, polyphenylene, polyethersulfone, polyimide, polyamide-imide, polyarylene-ether, polyphenylene sulfide, pholyarene ether ketone, Phenoxy resin, polycarbonate, polyetherimide, polyquinoxaline, polyquinoline, polybenzimidazole, polybenzoxazole, polybenzothazole or polyoxadiazole. In addition, the structural layer 112 a layer of silicon oxynitride (SiON) or silicon nitride (SiN) with low voltage. The voltage of the silicon oxynitride (SiON) is about 100 to 200 MPa.

The Silicon oxynitride (SiON) of low voltage provides a brittle material and is as a suspension structure educated. The suspension structure However, it must be capable of thousands of thermal voltage cycles to survive. A single layer of silicon oxynitride (SiON) of less Stress is not strong enough to withstand the influence of thermal Withstand tensions. Consequently, according to the present invention, a galvanically formed layer provided with a predetermined strength, which the suspension layer covered by silicon oxynitride (SiON). The electrodeposited layer is exposed to form a cross-connection structure train. The electrodeposited layer may be the suspension structure strengthen effectively, improve operating efficiency and increase service life.

The 3a - 3e FIG. 4 are schematic views showing a method of manufacturing the fluid injector. FIG 100 according to the 2 show, only the part P1 is shown.

A patterned sacrificial layer (not shown) is on a substrate 111 formed on a silicon wafer, for example, having a first surface and a second surface. The sacrificial layer comprises borophosphosilicate glass (BPSG), phosphosilicate glass (PSG) or silicon oxide. The sacrificial layer is deposited using chemical vapor deposition (CVD) or low pressure chemical vapor deposition (LPCVD) chemistry. In a typical process sequence becomes a structure layer 112 fitting on the first surface of the substrate 111 formed and covers the patterned sacrificial layer. The structural layer 112 includes a silicon oxynitride (SiON) or silicon nitride (SiN) of low voltage. The structural layer 112 can be deposited using chemical vapor deposition (CVD) or low pressure chemical vapor deposition (LPCVD). A fluid channel then becomes on the second surface of the substrate 111 trained and exposes the sacrificial layer (not shown). The sacrificial layer (not shown) is then removed to form a fluid chamber, as in FIG 3a shown.

According to the 3b is the fluid actuator 120 on the structural layer 112 outside the chamber 113 intended. The fluid actuator includes a thermal bubble generator or a piezoelectric thin film actuator. The fluid actuator is preferably a thermal bubble generator consisting of a resistive layer. The resistive layer includes HfB2, TaAL, TaN, or TiN. The resistive layer may be formed using a deposit vapor deposition (PVD), for example by vapor deposition, sputtering or reactive sputtering.

In a preferred embodiment, a patterned conductive layer (not shown) comprising Al, Cu or their alloys is formed around the structural layer 112 to cover, and this connects to the fluid actuator to act as a signal transmission circuit. The conductive layer may be deposited using a PVD process, such as by vapor deposition, sputtering or reactive sputtering. Subsequently, on the structural layer 112 a passivation layer 130 trained, as in the 3c shown, and is on the passivation layer 130 a galvanically formed layer 140 trained, as in the 3d shown. Finally, on the structural layer 112 a first through hole 114 is formed and is on the passivation layer 130 a third through hole 131 is formed and applied to the electrodeposited layer 140 a second through-hole 141 trained, as in the 3e shown. The first through hole 114 , the third through hole 131 and the second through-hole 141 communicate with each other and the first through hole 114 also communicates with the chamber 113 ,

It should be noted that the fluid actuator 120 from the electroplated layer 140 is covered, which on the passivation layer 130 can be coated by spin coating or spin coating, and that the structural layer 112 is a silicon oxynitride (SiON) or silicon nitride (SiN) of low stress.

It It should also be noted that the contact or wetting angle between the electrodeposited layer and water is about 90 ° or is larger and that the electrodeposited layer is preferably epoxy resin, Glycidyl methacrylate, acrylic resin, acrylate or methacrylate of one Novolac epoxy resin, polysulfone, polyphenylene, polyethersulfone, Polyimide, polyamide-imide, polyarylene-ether, polyphenylene sulfide, pholyarene ether ketone, Phenoxy resin, polycarbonate, polyetherimide, polyquinoxaline, polyquinoline, Polybenzimidazole, polybenzoxazole, polybenzothazole or polyoxadiazole is.

As stated above, is in the fluid injector according to this Embodiment the Improved integrity of the structure of the entire fluid injector, because the electrodeposited layer with a certain thickness outside the passivation layer is provided. Because the galvanic Layer with hydrophobic surface properties is provided, the fluid within the extended Nozzle retained become.

Because the length the injection path of the fluid to the additional thickness of the galvanic extended layer trained can also be the Direction of the injected or injected fluid more consistent be.

After this a micro-fluid droplet the opening has left, is streaming the fluid back into the fluid chamber and spreads over this the surface the fluid injector device out, what an overflow causes and for the next Injection process is disadvantageous.

Second embodiment

The 4 is a schematic view of a fluid injector 100d according to a second embodiment of this invention. The difference between the fluid injector 100a According to this embodiment and that according to the first embodiment is that the bubble generating device 120 only one heater 120a includes. The other elements in this embodiment are identical to those in the first embodiment; therefore, their description is omitted.

The Low-stress silicon oxynitride (SiON) is a brittle material and is on a suspension structure educated. The suspension structure however, it must be capable of thousands of thermal voltage cycles to resist. A single layer of silicon oxynitride (SiON) low tension is not strong enough to withstand the influence of withstand thermal stress. Consequently, according to the present Invention, a galvanically formed layer with a predetermined Thickness provided the suspending silicon oxynitride (SiON) covered. The electroplated layer is exposed to a structure to train with cross connections. The galvanically formed layer can the suspension structure indeed strengthen improve the efficiency of the operation and increase the service life.

Because the fluid injector according to this embodiment also provided with the electroplated layer, can be achieved with this same effect as with the first embodiment become. This means, the structural integrity of the entire fluid injector can be improved and the electroplated layer is with hydrophobic surface properties provided so that the fluid retained within the extended nozzle can be and the direction of the injected fluid more consistent can be.

Third embodiment

5a - 5c Fig. 3 are schematic views illustrating the steps of gray scale and grayscale lithography, respectively. The dimensions and profile of the second through-hole 141b can be controlled by using gray scale lithography. A gray scale mask modulates the intensity of ultraviolet (UV) light. The modulated light intensity will expose a photoresist with given depths. Once the exposed photoresist is developed, an increasing height profile remains in the partially exposed photoresist.

According to the 5a The gray scale mask provides different regions with different transmission coefficients. In the inner area of the through hole, the transmission coefficient for the light intensity is 0%. The transmission coefficient for the light intensity gradually increases up to 100% in the outer portion of the through hole. The incident light 600 traverses the grayscale mask pattern and generates a transmitted light 660 and a partially transmitted light 640 , A negative photosensitive, electroplated layer is coated with the transmitted light 660 and the partially transmitted light 640 exposed. The exposed, electroplated layer is designed to be in the 5b to achieve the shape shown. Like in the 5b is shown is the upper portion of the photoresist 141b wider than the lower section.

According to the 5c For example, the passivation layer and the structural layer are sequentially etched to form a first through-hole. The first through-hole communicates with the chamber and the second through-hole. In the fluid injector 100b , the Indian 4b is shown, the shape of the second through hole 141b unlike the shape of the second through-hole 141 in the 2 is shown. The diameter of one end of the second bore 141b that with the first through hole 114 communicates is much larger than that of the other end of the second through-hole 141b and the direction of the injected fluid can be more consistent.

Because the fluid injector according to this embodiment also provided with the electroplated layer, can achieve the same effect as in the first embodiment. The is called, the structural integrity of the entire fluid injector can be improved and the electrodeposited layer is with hydrophobic surface properties provided so that the fluid can be retained within the extended nozzle and the direction of the injected fluid can be more consistent.

Although the invention based on preferred embodiments in more specific The method has been illustrated and described, the expert in this field readily recognize that many changes and modifications can be made without departing from the general solution thoughts and to depart from the scope of the present invention. Therefore should the attached claims be designed so that this the disclosed embodiment, to include the alternatives discussed above as well as all equivalents.

The present application is a continuation-in-part application of US application Ser. 10 / 618,928, filed July 11, 2003, their disclosure hereby expressly incorporated by reference into the present application be.

In summary The invention relates to a fluid injector and a method for its production. The fluid injector includes a base, a first one Through-hole, a fluid actuator, a passivation layer and a thick hydrophobic layer. The base includes a chamber and a surface. The first through hole communicates with the chamber and is provided in the base. The fluid actuator is on the surface in the Near the provided first through hole and is located outside the chamber. The passivation layer is provided on the surface. The thick hydrophobic layer defines a second through-hole fixed and is provided on the passivation layer outside the chamber. The second through-hole communicates with the first through-hole.

Claims (14)

A fluid injector device comprising: a base ( 110 ), which has a chamber ( 113 ) and a surface comprises; a first through-hole ( 114 ) connected to the chamber ( 113 ) is communicated and provided in the base; an actuator or actuator ( 120 ), which is on the surface near the first through hole ( 114 ) and outside the chamber ( 113 ) the base is provided; a passivation layer ( 130 ) provided on the surface; and a galvanically formed layer ( 140 ), which has a second through-bore ( 141 ), is provided on the passivation layer outside the chamber, wherein the second Durchgangsboh tion ( 141 ) with the first through hole ( 114 ) communicates. A fluid injector according to claim 1, wherein the base ( 110 ) comprises: a silicon substrate ( 111 ); and a structural layer ( 112 ), which is provided on the silicon substrate, so that the chamber ( 113 ) is formed therebetween. A fluid injector according to claim 1 or 2, wherein the actuator ( 120 ) comprises a thermal bubble generator. A fluid injector according to claim 3, wherein said thermal bubble generating means comprises: a first heater (16); 121 ) located on the surface outside the chamber ( 113 ) is provided to generate a first bubble in the chamber; and a second heating device ( 122 ) located on the surface outside the chamber ( 113 ) is provided to generate in the chamber a second bladder to inject fluid into the chamber, the first heating means ( 121 ) and the second heating device ( 122 ) on opposite sides of the first through-hole ( 114 ) are located. A fluid injector according to claim 1 or 2, wherein the actuator ( 120 ) comprises a piezoelectric bubble generator. Fluid injector according to one of the preceding claims, wherein the second through-bore ( 141 ) is a through hole in the form of an upside down or upside - down funnel. Fluid injector according to one of the preceding claims, wherein the contact angle or wetting angle between the electrodeposited layer ( 140 ) and water is about 90 ° or larger. Fluid injector according to one of the preceding claims, wherein the electroplated layer ( 140 ) of an epoxy resin, glycidyl methacrylate, acrylic resin, acrylate or methacrylate of a novolak epoxy resin, polysulfone, polyphenylene, polyethersulfone, polyimide, polyamide-imide, polyarylene-ether, polyphenylene sulfide, polyarylene ether ketone, phenoxy resin, polycarbonate, polyetherimide, polyquinoxaline, polyquinoline , Polybenzimidazole, polybenzoxazole, polybenzothazole or polyoxadiazole is formed. A method of manufacturing a fluid injector, comprising the steps of: providing a substrate ( 111 ) having a first surface and a second surface; Forming a patterned sacrificial layer on the first surface of the substrate; Forming a patterned structural layer ( 112 ) on the first surface of the substrate covering the patterned sacrificial layer; Forming an actuator or actuating element ( 120 ) on the structural layer ( 112 ), wherein the fluid actuator ( 120 ) outside the chamber ( 113 ) is located; Forming a passivation layer ( 130 ) on the passivation layer or structural layer ( 112 ), which the fluid actuator ( 120 covered); Forming a galvanically formed layer ( 140 ) on the passivation layer ( 130 ); Forming a fluid channel in the second surface of the substrate opposite the first surface and exposing the sacrificial layer; and removing the sacrificial layer to a chamber ( 113 ) train. Method according to Claim 9, in which the contact angle or wetting angle between the electrodeposited layer ( 140 ) and water is about 90 ° or larger. Process according to claim 9 or 10, wherein the galvanic formed layer of epoxy resin, glycidyl methacrylate, acrylic resin, Acrylate or methacrylate of a novolak epoxy resin, polysulfone, Polyphenylene, polyethersulfone, polyimide, polyamide-imide, polyarylene-ethers, Polyphenylene sulfide, pholyarene ether ketone, phenoxy resin, polycarbonate, Polyetherimide, polyquinoxaline, polyquinoline, polybenzimidazole, polybenzoxazole, Polybenzothazole or polyoxadiazole is formed. Method according to one of claims 9 to 11, wherein the electrodeposited layer by spin coating or spin-coating on the passivation layer ( 130 ) is piled up. Method according to one of claims 9 to 11, wherein the galvanic formed layer by rolling piled on the passivation layer becomes. The method of any one of claims 9 to 13, wherein the step of forming a nozzle comprises: forming a second through-bore (10); 141 ) in the electroplated layer ( 140 ) by grayscale or grayscale lithography, wherein the second through-bore ( 141 ) is a through-hole in the form of an inverted or upside-down funnel; sequential etching of the passivation layer ( 130 ) and the structural layer ( 112 ) along the second through-hole to a first Durchgangsboh tion ( 114 ), wherein the first through hole with the chamber ( 113 ) and the second through-bore ( 141 ) communicates.