Abstract: A micro-fluid ejection head and methods for improving the fabrication and operation of the micro-fluid ejection head. The ejection head includes a photoimaged thick film layer attached to a substrate containing fluid ejection actuators. An orifice plate is laminated to the thick film layer. The orifice plate has a plurality of concentric orifices therein and is derived from a first photoresist material that is heated to a temperature sufficient to relieve film stresses in the photoresist material prior to exposing and developing the orifices in the orifice plate.

Abstract: A through-hole forming method includes steps of forming a first impurity region (102a) around a region where a through-hole is to be formed in the first surface of a silicon substrate (101), the first impurity region (102) being higher in impurity concentration than the silicon substrate (101), forming a second impurity region (102b) at a position adjacent to the first impurity region (102a) in the depth direction of the silicon substrate (101), the second impurity region (102b) being higher in impurity concentration than the first impurity region (102a), forming an etch stop layer (103) on the first surface, forming an etch mask layer (104) having an opening on the second surface of the silicon substrate (101) opposite to the first surface, and etching the silicon substrate (101) until at least the etch stop layer (103) is exposed via the opening.

Abstract: In a method of forming micro traces, stamping techniques are employed to define a target pattern of the micro traces. The stamping is applied to electrically conductive material and may be limited to pressure, but a thermal stamping approach may be utilized. Following the stamping, a portion of the conductive material is removed, leaving the target pattern of conductive micro traces. In the pressure-application step, the pressure or the combination of pressure and temperature is sufficient to at least weaken the integrity of the bulk conductive material along the area of contact. Typically, this step causes shearing of the conductive material. Following the pressure-application step, excess conductive material is removed. In some embodiments of the invention, the thickness of the micro traces is not determined in a single step. The original thickness may be formed using a “seed” material. The subsequent material buildup may occur after the target pattern is established.

Abstract: An AlGaN composition is provided comprising a group III-Nitride active region layer, for use in an active region of a UV light emitting device, wherein light-generation occurs through radiative recombination of carriers in nanometer scale size, compositionally inhomogeneous regions having band-gap energy less than the surrounding material. Further, a semiconductor UV light emitting device having an active region layer comprised of the AlGaN composition above is provided, as well as a method of producing the AlGaN composition and semiconductor UV light emitting device, involving molecular beam epitaxy.

Abstract: Integrated circuits and methods for producing them are provided. In particular, integrated circuits with shielding elements are provided.

Abstract: Embodiments of a printhead are disclosed.

Abstract: There is provided a liquid discharge apparatus which includes a liquid channel which connects a discharge port and a pressure chamber; a piezoelectric layer one surface of which facing the pressure chamber; a power feeding electrode which applies a voltage to the piezoelectric layer; and a liquid electroconductive material which electrically connects the other surface of the piezoelectric layer and the power feeding electrode, and in an area on the other surface, of the piezoelectric layer, overlapping with the pressure chamber, a contact area which is an electrical contact between the piezoelectric layer and the liquid electroconductive material is formed. Accordingly, it is possible to provide a liquid discharge apparatus which is capable of realizing a small size channel unit and an improvement in a resolution of an image which is formed by a discharging liquid, and to change appropriately a shape of the piezoelectric layer.

Abstract: A method of bonding an integrated circuit to a substrate is provided. The integrated circuit is one of a plurality of integrated circuits, each having a respective frontside releasably attached to a film frame tape supported by a wafer film frame. The method comprises the steps of: (a) positioning a substrate at a backside of the integrated circuit; (c) positioning a bonding tool on a zone of the film frame tape, the zone being aligned with the integrated circuit; and (c) applying a bonding force from the bonding tool, through the film frame tape and the integrated circuit, onto the substrate.

Abstract: A method of bonding a first substrate to a second substrate is provided. The method comprises the steps of: (a) providing a first substrate having a plurality of etched trenches defined in a first bonding surface; (b) providing a second substrate having a second bonding surface; and (c) bonding the first bonding surface and the second bonding surface together using an adhesive. During bonding, the adhesive is received, at least partially, in the plurality of etched trenches, thereby increasing the adhesive bond strength whilst avoiding surface roughening. The method is particularly suitable for bonding semiconductor chips using liquid adhesives.

Abstract: A method of fabricating an ink jet head having a metal chamber layer includes preparing a substrate having pressure-generating elements to generate pressure to eject ink ejection. The metal chamber layer to define sidewalls of an ink flow path is then formed on the substrate. A sacrificial layer is formed to fill a region where the ink flow path is to be formed between the sidewalls defined by the metal chamber layer. A nozzle layer having nozzles corresponding to the pressure-generating elements is formed on the metal chamber layer and the sacrificial layer.

Abstract: A manufacturing method of an ink jet recording head including a discharge port for discharging ink includes the step of forming the discharge port by performing dry etching of a discharge port forming member for forming the discharge port, wherein the discharge port forming member is formed of a Si including resin, and the step of dry etching is performed by using an etching gas including oxygen and chlorine as necessary components.

Abstract: A method of manufacturing an orientation film which method is suitable for manufacturing an orientation film containing a ceramic at low cost. The method includes the steps of: (a) forming a ceramic film on a seed substrate in which crystal orientation is controlled at least on a surface thereof by using an aerosol deposition method of injecting powder toward a substrate and depositing the powder on the substrate; and (b) heat-treating the ceramic film formed at step (a) to form an orientation film in which crystal grains contained in the ceramic film is oriented.

Abstract: A method for producing an inkjet head for jetting an ink from a nozzle that is formed on a nozzle main body formed of a metal material, the method includes smoothening a surface of the nozzle main body, applying a silica sol solution to the nozzle main body so as to form a silica sol film, wherein the silica sol solution has a concentration that is controlled to avoid a nozzle clogging in the nozzle main body, heating the silica sol film formed on the nozzle main body to thereby convert the silica sol film into an SiO2 film, applying an ink repellent agent solution to the SiO2 film and drying to thereby form an ink repellent film, wherein the ink repellent agent solution is prepared by dissolving a compound having an alkoxysilane residue at an end of a perfluoro polyether chain in a solvent.

Abstract: In a method of manufacturing a semiconductor thin film piece device, a plurality of semiconductor thin film pieces (14) are selected from among the semiconductor thin film pieces (14) formed on a first substrate (35), and bonded to a first set of predetermined area on a second substrate (12). Subsequently, a plurality of semiconductor thin film pieces are selected from the remaining semiconductor thin film pieces (14), and bonded to a second set of predetermined area.

Abstract: An ink-jet head and a method of manufacturing the ink-jet head are disclosed. The ink-jet head may include: an upper substrate, formed by processing a chamber in a silicon substrate; a middle substrate, bonded to the upper substrate and formed by processing an ink channel, which connects with the chamber, in a glass substrate; and a lower substrate, bonded to the middle substrate and formed by processing a nozzle, which connects with the ink channel, in a silicon substrate. With certain embodiments of the invention, a high level of precision may be obtained for the structures formed in the upper substrate and the lower substrate, and the middle substrate may be manufactured in low cost. Also, the substrates may be bonded together in a facilitated manner, so that production yield may be increased.

Abstract: A method of manufacturing a thermal print head includes a conductor layer formation step, a first measurement step, a conductor layer splitting step and a second measurement step. In the conductor layer formation step, a single conductor layer including first and second measurement points is formed on a substrate. In the first measurement step, the electrical resistance is measured in the conductor layer, between the first and the second measurement points. In the conductor layer splitting step, a predetermined portion of the conductor layer is removed, so that a first electrode including the first measurement point and a second electrode including the second measurement point are formed. In the second measurement step, the resistance between the first and the second electrodes is measured. If the conductor layer has a disconnected portion in the first measurement step, a repairing conductor is formed on the disconnected portion.

Abstract: A method of forming a nozzle rim for a nozzle aperture is provided. The method is suitable for forming part of a printhead fabrication process. The method comprises the steps of: (a) depositing a roof material layer over a sacrificial layer; and (b) removing a first part of said roof material layer so as to form a nozzle rim.

Abstract: A microfluidic device includes first and second glass substrates bonded together. The first glass substrate has first and second opposed surfaces. A die pocket is formed in the first opposed surface, and a through slot extends from the die pocket to the second opposed surface. The second glass substrate is bonded to the second opposed surface of the first glass substrate whereby an outlet of a channel formed in the second glass substrate substantially aligns with the through slot. The channel of the second glass substrate has an inlet that is larger than the outlet.

Abstract: Provided is a printhead for an inkjet printer. The printhead has a plurality of micro-electromechanical ejection mechanisms arranged in a wafer substrate, with each mechanism having chamber walls and a roof formed on top of said substrate to define an ink chamber. One wall of the chamber defines a slot therein. The mechanism also includes an ink supply channel defined through the substrate to said chamber. The mechanism includes a bi-layer thermal actuator coil fast with the substrate and ending in a strut extending through the slot, said strut fast with a paddle device within the chamber.

Abstract: A method of fabricating a MEMS inkjet type print head and the resulting device is disclosed. The method includes providing a driver component and separately providing an actuatable membrane component, the actuatable membrane component being formed in the absence of an acid etch removing a sacrificial layer. The separately provided actuatable membrane component is bonded to the driver component and a nozzle plate is attached to the actuatable membrane component subsequent to the bonding. Separately fabricating the components removes the need for hydrofluoric acid etch removal of a sacrificial layer previously required for forming the actuatable membrane with respect to the driver component.

Abstract: A method of forming an enclosed fluid path in a print head includes providing a die member and a truncated nozzle plate spaced from the upper surface of the die member. The die and nozzle plate are formed on a print head substrate having an aperture formed therein. A sacrificial material is seated over the aperture of the print head substrate and joins a terminal end of the truncated nozzle plate. The sacrificial material is encapsulated from the terminal end of the nozzle plate to a surface of the print head substrate. Removal of the sacrificial material defines the fluid path from the aperture of the print head substrate to the nozzle plate.

Abstract: A method of fabricating a plurality of MEMS integrated circuits from a wafer having a MEMS layer formed on a frontside thereof and a polymer coating over said MEMS layer, said polymer coating having a plurality of frontside dicing streets defined therethrough, said method comprising the steps of: (a) releasably attaching a first holding means to said polymer coating; and (b) performing at least one operation on a backside of the wafer, said at least one operation including etching a plurality of backside dicing streets through the wafer, each backside dicing street meeting with a respective frontside dicing street, thereby providing the plurality of MEMS integrated circuits releasably attached to said first holding means, wherein each MEMS integrated circuit comprises a respective polymer coating.

Abstract: A fluid distribution stack (500) for distributing fluid to a printhead integrated circuit (51), the fluid distribution stack (500) including a lower layer (530) having a lower channel (531, 532), the lower channel (531, 532) being configured to allow for fluid flow, a middle layer (520) having a hole (521, 522), the middle layer (520) being connected to the lower layer (530) such that the hole (521, 522) is in fluid communication with the channel (531, 532) of the lower layer and an upper layer (510) having a receptacle (511, 513), the upper layer (510) being connected to the middle layer (520) such that the receptacle (511, 513) is in fluid communication with the hole of the middle layer (520), wherein the printhead integrated circuit (51) is connected to the upper layer (510) such that fluid from the lower layer (530) is distributed to the printhead integrated circuit (51).

Abstract: A method of manufacturing a recording head according to the present invention includes a plurality of steps to describe as follows. In a solder paste application step, solder paste bodies are partially applied onto a plurality of terminals. In a heating step, each of the plurality of solder paste bodies is heated, to thereby form a plurality of solder layers on the plurality of terminals. In a covering step, the plurality of terminals and the plurality of solder layers are covered by an uncured synthetic resin layer. In a contact step, a plurality of bumps formed in a bump forming step and the plurality of solder layers are contacted with each other, by pressing regions of the synthetic resin layer covering the solder layers and the bumps to each other. In a curing step, the uncured synthetic resin layer is cured.

Abstract: Provided, in one embodiment, is a method for manufacturing a resistive structure. This method, without limitation, includes forming a substrate, and forming a tantalum-aluminum-nitride resistive layer over the substrate. Moreover, a bulk resistivity of the tantalum-aluminum-nitride resistive layer may be adjusted by varying at least one deposition condition selected from the group consisting of a flow rate ratio of nitrogen to argon, power, pressure, temperature and radio frequency (RF) bias voltage.

Abstract: There is provided a head including a chip 10 that has a semiconductor substrate 11, heating elements 12 disposed on the semiconductor substrate 11, coating layers 14 disposed on the semiconductor substrate 11 and having nozzles 14a arranged in regions above the respective heating elements 12, and individual channels 14b each communicating with the outside and the region above the corresponding heating element 12, wherein the semiconductor substrate 11 does not have a through hole communicating with each individual channel 14b; a ink feed member 21 having a common channel 21b, the ink feed member 21 being bonded to the chip 10 in such a manner that the common channel 21b communicates with the individual channels 14b; and a top 22 disposed on the chip 10 and the ink feed member 21 so as to seal the opening of the common channel 21b.

Abstract: A method of forming a fluid ejection device includes forming a pair of first glass layers and forming a second glass layer. Each first glass layer includes a first side and a second side with the second side defining a first fluid flow structure. The second glass layer includes a first side and a second side opposite the first side, with each respective first side and second side defining a second fluid flow structure. The second glass layer is bonded in a sandwiched position between the respective first glass layers with each respective second fluid flow structure of the second glass layer in fluid communication with the respective first fluid flow structure of the respective first glass layers to define a fluid flow pathway for ejecting a fluid.

Abstract: A method of fabricating a printhead integrated circuit includes the step of forming a first layer of a polymeric material on a substrate that incorporates drive circuitry. A heater element is formed on the first layer of polymeric material to be connected to the drive circuitry. A second layer of a polymeric material is formed on the heater element and the first layer such that the heater element is embedded in polymeric material. The polymeric layers are etched to define a plurality of radially extending bridging portions which terminate in a nozzle rim and a plurality of actuators which each extend between a respective pair of adjacent bridging portions and each terminate in a free end proximal to the rim. The substrate is etched so that the substrate and the actuators define a nozzle chamber in fluid communication with an ink ejection port defined by the nozzle rim.

Abstract: Methods of micro-machining a semiconductor substrate to form through fluid feed slots therein. One method includes providing a semiconductor substrate wafer having a thickness greater than about 500 microns and having a device side and a back side opposite the device side. The back side of the wafer is mechanically ground to provide a wafer having a thickness ranging from about 100 up to about 500 microns. Dry etching is conducted on the wafer from a device side thereof to form a plurality of reentrant fluid feed slots in the wafer from the device side to the back side of the wafer.

Abstract: An ink jet head circuit board is provided which has heaters to generate thermal energy for ink ejection as they are energized. This circuit board has the heaters formed with high precision to reduce their areas. It also has provisions to protect the electrode wires against corrosion and prevent a progress of corrosion. The substrate is deposited with the thin first electrodes made of a corrosion resistant metal. This is further deposited with the resistor layer. The second electrodes made of aluminum are deposited to overlap the first electrodes to form the heater without causing large dimensional variations among the heaters. With this construction, if a defect should occur in a protective layer on or near the heater, a progress of corrosion can effectively be prevented because the material of the resistor layer is more resistant to encroachment than aluminum and the first electrodes are corrosion resistant.

Abstract: The nozzle plate has a nozzle hole formed therethrough, the nozzle hole being defined in the nozzle plate with an inner surface including a first liquid-philic portion, a liquid-phobic portion and a second liquid-philic portion that are arranged in this order from a side near the nozzle mouth, the first and second liquid-philic portions having liquid-philicity, the liquid-phobic portion having liquid-phoblicity.

Abstract: A MIS type semiconductor device and a method for fabricating the same characterized in that impurity regions are selectively formed on a semiconductor substrate or semiconductor thin film and are activated by radiating laser beams or a strong light equivalent thereto from above so that the laser beams or the equivalent strong light are radiated onto the impurity regions and on an boundary between the impurity region and an active region adjoining the impurity region.

Abstract: A method for producing a liquid-jet head comprises the steps of: forming a vibration plate and piezoelectric elements on one surface of a passage-forming substrate, and removing the vibration plate in a region to be a communicating portion, thereby forming an exposed portion; forming a wiring layer on the passage-forming substrate within the exposed portion, and forming lead electrodes; bonding a reservoir forming plate to the one surface of the passage-forming substrate; wet-etching the passage-forming substrate at the other surface thereof to form pressure generating chambers and the communicating portion; forming a liquid-resistant protective film on inner surfaces of the pressure generating chambers and the communicating portion; removing the protective film within the exposed portion; and performing wet etching on the communicating portion side to remove the wiring layer, thereby establishing communication between a reservoir portion and the communicating portion.

Abstract: A method for forming a printhead having a very high dot-per-inch printing capability is described. The method includes forming a layer containing electronic control circuits upon a semiconductor wafer. Nozzle chambers are then etched into the wafer and corresponding fluid ejection assemblies are formed for each nozzle chamber. Ink inlets for the nozzle chambers are produced by back-etching through the wafer. Steps for fabricating thermal bend actuators to eject ink from the nozzles are also described.

Abstract: An ink-jet recording head includes a substrate which has a first surface, a second surface opposed to the first surface, and energy-generating elements arranged above the first surface and configured to generate energy used to discharge ink. The recording head also includes discharge ports through which the ink is discharged and arranged to correspond to the energy-generating elements, ink channels communicatively connected to the discharge ports, a supply port which extends from the first surface to the second surface of the substrate and which is communicatively connected to the ink channels, and a film extending over the wall of the supply port. The film further extends on the first surface of the substrate and is covered with a first layer extending from the first surface of the substrate.

Abstract: The present invention provides a method of manufacturing a pattern with a flattened surface and a droplet jetting device which can provides the pattern with a flattened surface. A droplet jetting means of the present invention comprises a droplet jetting means having a plurality of nozzles arranged in each row, each of the plurality of nozzles has a plurality of discharge ports aligned in an axial direction, and diameters of the discharge ports for the plurality of nozzles differ from row to row.

Abstract: Grooves forming a thin-film transistor (TFT) pattern are formed on the surface of a roller. A tank supplies ink including semiconductor materials to the roller. A squeegee embeds the ink supplied to the roller into the grooves formed on the surface thereof. The roller transfers the ink embedded in the grooves onto a substrate. With this arrangement, the processing time for forming substrates is shortened.

Abstract: A nozzle of an ink jet printer is formed by initially providing a silicon wafer having a circuitry wafer layer including electrical circuitry necessary for the operation of the thermal actuators on demand. The actuator is formed by forming a first inert material layer defining an actuator path in the shape of a planar coil starting at the thermal actuator anchor. Then, a first conductive material layer is formed adjacent the actuator path and attached to the first inert material layer.

Abstract: A liquid ejection head includes a substrate including, at a surface thereof, an ejection energy generating means for generating ejection energy for ejecting liquid, a flow path forming member provided with an ejection outlet, the substrate further including a liquid supply opening, penetrating therethrough, for supplying the liquid to be ejected by the ejection energy to a flow path of the flow path forming member; a reinforcing member connected to a back side of the substrate; a first penetrating electrode, penetrating the substrate from a front side to the back side thereof, for supplying electric power to the ejection energy generating means; and a second penetrating electrode penetrating the reinforcing member from a front side to a back side thereof, the second penetrating electrode being electrically connected to the first penetrating electrode.

Abstract: Aspects of the invention provide a manufacturing method enabling a fine layer pattern to form it precisely and stably. An exemplary method for manufacturing a layer pattern can include a step (a) of forming a region defined by a first layer and a second layer on a substrate and a step (b) of ejecting a liquid like material to the region from an ejecting part of an ejecting device. Here, the first layer can be formed on the substrate and the second layer can be located on the first layer. A lyophobicity of the first layer to the liquid like material is lower than the lyophobicity of the second layer to the liquid like material.

Abstract: A method for manufacturing a CMOS image sensor is provided. The method includes forming a gate electrode on a semiconductor layer having defined regions of a photodiode region and a logic region, such that a gate oxide film is interposed between the semiconductor layer and the gate electrode; forming sidewall insulating films at both sides of the gate electrode, followed by forming a salicide-preventing film over an overall surface of the gate electrode and insulating films; removing the salicide-preventing film formed in the logic region; and removing a portion of the sidewall insulating films exposed by removing the salicide-preventing film, thereby exposing an upper side surface of the gate electrode.

Abstract: A method is provided for manufacturing an inkjet nozzle. The method includes the step of depositing a plastics material layer on a substrate incorporating heater actuator circuitry. The plastics material layer is etched to form a nozzle rim defining an ink port through which ink can be ejected and a plurality of elongate actuator arms extending radially with respect to the nozzle rim. A tapered ink chamber may be etched in the nozzle body so that the ink port and ink chamber are in fluid communication with each other.

Abstract: In a method of manufacturing a liquid discharge head, liquid in a pressure generation chamber is pressurized by a piezoelectric driving force of a piezoelectric element, and is discharged from a nozzle communicated with the pressure generation chamber. The method is characterized by the steps of providing a flow passage substrate incorporating the pressure generation chamber, anodically joining a diaphragm to the flow passage substrate, forming electrode layers and a piezoelectric film of the piezoelectric element on the diaphragm, and crystallizing the piezoelectric film during or after the lamination at a crystallization temperature not higher than a strain point of the diaphragm.

Abstract: Disclosed is a method of manufacturing a liquid jet head, which enables a passage-forming substrate to be easily handled, thus realizing good formation of pressure generating chambers and an improvement in manufacturing efficiency. The method includes the steps of: forming a vibration plate and piezoelectric elements on one surface of the passage-forming substrate; thermally adhering a reinforcing substrate for reinforcing the rigidity of the passage-forming substrate, onto the passage-forming substrate; processing the passage-forming substrate to have a predetermined thickness; depositing an insulation film on other surface of the passage-forming substrate at lower temperature than that for adhering the passage-forming substrate and the reinforcing substrate, and patterning the insulation film into a predetermined shape; and etching the passage-forming substrate using the patterned insulation film as a mask to form the pressure generating chambers.

Abstract: A method of fabricating an inkjet printhead with a wafer substrate that has an ink ejection side and an opposing ink inlet side. The printhead has an array of nozzles formed on the ink ejection side, and an array of ink inlets formed in the ink inlet side. Each nozzle is individually associated with a respective ink inlet. The method comprises the steps of forming the array of nozzles using lithographically masked etching and deposition techniques, and, etching individual feed paths through the wafer substrate between each of the nozzles and its associated ink inlet. Feeding the ink to the nozzles by individual feed paths through the wafer, increases the nozzle packing density and the resolution.

Abstract: An ink jet printhead chip that is manufactured in accordance with an integrated circuit fabrication technique includes a wafer substrate that defines a plurality of nozzle chambers as a result of an etching process. An etch stop layer is positioned on a front side of the wafer substrate so that portions of the etch stop layer define a roof wall for each nozzle chamber, each said portion defining at least one ink ejection port, also a result of an etching process carried out on each portion. A plurality of actuators are arranged on a back side of the wafer substrate, each actuator being operatively positioned relative to each respective nozzle chamber to eject ink from the nozzle chambers.

Abstract: An improved photoimaged nozzle plate for a micro-fluid ejection head, a micro-fluid ejection head containing the nozzle plate, and methods for making a micro-fluid ejection head. The improved nozzle plate is provided by a photoresist nozzle plate layer applied to a thick film layer on a semiconductor substrate containing fluid ejector actuators. The photoresist nozzle plate layer has a plurality of nozzle holes therein. Each of the nozzle holes are formed in the nozzle plate layer from an exit surface of the nozzle plate layer to an entrance surface of the nozzle plate layer. Each of the nozzle holes has a reentrant hole profile with a wall angle greater than about 4° up to about 30° measured from an axis orthogonal to a plane defined by the exit surface of the nozzle plate layer.

Abstract: A print head includes a substrate and an ejector. The substrate includes a first side and a second side. The ejector is located on the first side of the substrate and includes a fluid chamber with portions of the fluid chamber defining a nozzle bore, and a resistive element operable to eject fluid present in the fluid chamber through the nozzle bore of the fluid chamber. The resistive element is electrically connected to the substrate. A conductor is located on the second side of the substrate and is electrically connected to the substrate. A supply passage is located through the conductor and the substrate and is in fluid communication with the fluid chamber of the ejector to supply a fluid to the fluid chamber.

Abstract: A method of forming an opening through a substrate having a first side and a second side opposite the first side includes forming a trench in the first side of the substrate, forming a mask layer within the trench, filling the trench with a fill material, forming a first portion of the opening in the substrate from the second side of the substrate toward the mask layer, and forming a second portion of the opening in the substrate through the mask layer and the fill material, including communicating the second portion of the opening with the first portion of the opening and the first side of the substrate.

Abstract: A method is provided for manufacturing a printer nozzle. The method includes the step of depositing a metal layer upon a semi-conductor wafer. The metal layer defines a pair of protruding portions which each form a respective electrical contact. The method further includes the step of etching the metal layer through to the wafer to form a nozzle region and to electrically isolate the electrical contacts. In one embodiment, the nozzle region is defined by a circular wall.