JP2002537132A - Thermal bending actuator and paddle structure for inkjet nozzle - Google Patents

Abstract

A thermal actuator (7) for micro electromechanical systems (MEMS) comprises two arms (10, 11), with a gap between them for improving operational characteristics and reducing shear stress, where one arm is arranged to undergo thermal expansion to cause the actuator to bend. The actuator (7) may be used to operate a paddle (8) for an ink jet nozzle chamber (2). An aperture in the nozzle chamber (2) has a raised rim (19) for forming a meniscus with the actuator (7), for preventing leakage from the nozzle chamber (2). The paddle (8) has a structural support portion (18) which acts as a spacer to prevent contact between the paddle (8) and a meniscus (3) at the nozzle (4). The nozzle chamber (2) has an internal protrusion, aligned with and opposite to the paddle (8) in its non-ejection state, which aids rapid refill of the nozzle chamber (2) after ejection.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001] The present invention relates to the field of micromechanical or microelectromechanical devices such as ink jet printers. The present invention is described herein with reference to micro-electromechanical inkjet technology. However, the present invention has broader application to other micromechanical or microelectromechanical devices, such as microelectromechanical pumps and microelectromechanical movers. [Background of the Invention]

[0002] Micro-mechanical and micro-electro-mechanical devices are becoming increasingly popular and typically involve the creation of devices on the micrometer (micron) scale using semiconductor manufacturing techniques. For a recent overview of micromechanical devices, see S. Tom, IEEE Spectrum, December 1998, pp. 24-33.
`` The Broad Sweep of Integrated Micro Sy '' by Picraux and Paul J. McWhorter
stems ".

One type of commonly used microelectromechanical device is an ink jet printing device in which ink is ejected from an ink ejection nozzle chamber. Many types of inkjet devices are known. Many different technologies for inkjet printing and related devices have been invented. For an overview of this field, see Output Hard C, edited by R Dubeck and S Sherr.
`` Non-Impact Printin '' by J Moore, op.
g: Introduction and Histrical Perspective.

Recently, the Applicant has proposed a micro-electromechanical inkjet (
A new type of ink jet printing, called MEMJET technology, has been developed.
In one form of MEMJET technology, ink is ejected from an ink ejection nozzle chamber that utilizes an electromechanical actuator connected to a paddle or plunger. The paddle or plunger moves toward the ejection nozzle of the chamber to eject ink droplets from the ejection nozzle chamber.

The present invention is directed to improvements in mechanical bending actuators for use in MEMJET technology and other micromechanical or microelectromechanical devices.

SUMMARY OF THE INVENTION According to a first aspect of the present invention, there is provided a thermal actuator for a micro-electromechanical device. The actuator is a support substrate, an actuating part, and a first arm attached to the substrate at a first end thereof and attached to the actuating part at a second end, such that during use the heat can be heated by conduction. And a second arm attached to the support substrate at a first end and attached to the actuation portion at a second end, spaced apart from the first arm. Disposed, whereby the first and second arms define a gap therebetween.
A second arm. In use, the first arm is arranged to thermally expand when heated by conduction, thereby applying a force to the actuation portion.

[0007] Thus, the dependence of the operating characteristics of the actuator, such as operating temperature, on the material of the operating part can be reduced as compared to the prior art thermal actuator. In prior art thermal actuators, the actuating part is usually partially disposed between the arms of the thermal actuator (three-layer actuator). Further, if the actuator is partially disposed between arms, during use, shear stress may be induced in that portion of the actuator, thereby reducing the efficiency of the actuator. There is. The actuator may be arranged in such a way that a heating current can be applied to the first arm through the support substrate.

[0008] The first and second arms are preferably formed from substantially the same material. The actuator depositing and etching the first layer to form a first arm;
Depositing and etching a second layer to form a sacrificial layer support structure above the first arm; depositing and etching a third layer to form a second arm;
Forming a gap between the first arm and the second arm by etching a layer of the second arm.

The first arm may include, at a second end, two elongated flexible strips interconnected by conduction. The second arm may include two elongated flexible strips. The actuation portion may include a paddle structure. Therefore, the actuator may be used in the liquid ejection chamber while the paddle structure is movable with respect to ejection of the liquid from the liquid ejection chamber. The first arm may be formed from titanium nitride, and the second arm may be formed from titanium nitride.

According to a second aspect of the present invention, a novel form of manufacturing an inkjet printing system is disclosed.

According to a third aspect of the present invention, there is provided a paddle for ejecting liquid from within a nozzle chamber through a liquid ejection nozzle defined at one wall of the nozzle chamber. A paddle is formed on the plunger surface at a first portion configured to provide a generally flat plunger surface facing the nozzle and spaced from the nozzle during use, and a perimeter of the first portion. A second portion that provides structural support for the first portion, such that in use the plunger is actuated and ejects liquid through the nozzle while the second portion forms a spacer. And prevents the plunger surface from touching the nozzle.

[0012] The spacing of the plunger surface from the nozzle is important to reduce the likelihood of the liquid meniscus contacting the plunger surface at the nozzle. Contact can affect the operating characteristics of such devices. A person skilled in the art would correspondingly perform a chamber embodying the present invention at the same ejection volume as compared to a paddle having a constant thickness, which was previously deemed necessary for structural rigidity. It can be appreciated that the size of the can be reduced.

[0013] The second portion may be configured to define a continuous wall structure around the central portion, with the central portion of the plunger surface substantially aligned with the nozzle during use. The central portion may preferably be of the same dimensions as the nozzle. The first portion may have a circular outer periphery, and the second portion may include an annulus around the outer periphery of the paddle. The paddle may be disposed substantially symmetrically around the liquid ejection nozzle, wherein the first layer is deposited and etched to form a first paddle portion, and the second layer is deposited and etched. Forming a sacrificial layer support structure above the first paddle portion,
Forming a third paddle portion by accumulating and etching a layer of the third layer.

According to a fourth aspect of the present invention, there is provided a mechanical actuator for a micro-mechanical or micro-electro-mechanical device. Such an actuator is a support substrate, an actuating part and a first arm attached to the substrate at a first end thereof and attached to the actuating part at a second end thereof, which can be heated by conduction during use. And a second arm attached to the support substrate at a first end and attached to the working portion at a second end, the first arm being spaced apart from the first arm. And a second arm, wherein the first and second arms define a gap therebetween.
Two rigid members interconnect the first arm and the second arm between the first end and the second end thereof, wherein in use the first arm thermally expands, thereby causing the actuator to expand. Are arranged to apply a force to the working part.

The applicant can prevent the two arms from warping when the first arm expands by providing a rigid member between the first arm and the second arm.
I discovered that.

The first arm is preferably connected to the first main body, formed between the first end and the second end of the first arm, and the first main body. And at least one tab body, wherein a first one of the at least one rigid member may interconnect the tab with the second arm. The second arm preferably has a second main body formed between a first end and a second end of the second arm, and at least one main body connected to the second main body. And a corresponding tab body, wherein the first of the at least one rigid member may interconnect the corresponding tabs of the first and second arms.

[0017] The tab body may be connected to the first main body through a first thinned neck. A corresponding tab body may be connected to the second main body through a second thinned neck.

The first arm, whereby the first arm can be heated by conduction;
The first arm may include a conductive layer that causes the first arm to thermally expand with respect to the second arm during use, thereby causing the actuator to apply a force to the actuator. The first and second arms are preferably substantially parallel, and the rigid member may be substantially perpendicular to the first and second arms. The actuator may be arranged in such a way that current can be supplied to the conductive layer through the support substrate. The first and second arms are preferably formed from substantially the same material.

The actuator includes a step of depositing and etching a first layer to form a first arm, and a step of depositing and etching a second layer to form a sacrificial layer support structure above the first arm. Forming, forming and etching a third layer to form a second arm, and etching a sacrificial layer to form a gap between the first arm and the second arm And a manufacturing process.

The first arm may include, at a second end, two elongated flexible strips interconnected by conduction. The second arm may also include two elongated flexible strips. The actuation portion may include a paddle structure. Therefore, the actuator may be used in the liquid ejection chamber while the paddle structure is movable with respect to ejection of the liquid from the liquid ejection chamber. The first conductive arm may be formed from titanium nitride, and the second arm may be formed from titanium nitride.

According to a fifth aspect of the present invention, there is provided a thermal actuator for a micro-mechanical or micro-electro-mechanical device. Such an actuator is a support substrate, an actuator extension, and a first arm attached to the substrate at a first end thereof and attached to the extension at a second end,
A first arm adapted to be heatable by conduction during use; a second arm attached to the support substrate at a first end and to an extension at a second end.
Wherein the first arm thermally expands during use, thereby causing the actuator to exert a force on the extension. , Wherein the first arm includes at least one heat sink element at approximately the highest heating point of the first arm, where the highest heating of the first arm occurs during use.

Applicants can achieve a more uniform temperature profile by providing a heat sink element in that the maximum temperature in the first arm can be reduced and throughout the first arm. In this regard, it has been discovered that the operating characteristics of an actuator that bends due to heat can be improved. This can maximize the thermal expansion induced in the first arm.

[0023] The heat sink element may be disposed substantially at the center of the first arm. A heat sink element may be arranged to interconnect the first arm and the second arm. The heat sink element may include at least one tab body connected to the main body of the first arm. The tab body may be connected to the main body through a first thinned neck. The first arm may include a conductive layer by which the first arm can be heated by conduction.

[0024] The actuators may be arranged in such a way that current can be supplied to the conductive layer through the support substrate. The first and second arms are preferably formed from substantially the same material. The extension may include a paddle structure. Therefore, the actuator may be used in the liquid ejection chamber while the paddle structure is movable with respect to ejection of the liquid from the liquid ejection chamber. The first conductive arm may be formed from titanium nitride, and the second arm may be formed from titanium nitride.

According to a sixth aspect of the present invention, a first opening in one wall thereof for ejecting liquid and a second opening in the wall through which the actuator arm extends. A liquid ejection device is provided that includes a nozzle chamber having a portion. The arm of the actuator is attached to a substrate located outside the nozzle chamber and is connected to a paddle inside the nozzle chamber, the paddle ejecting liquid through the first opening by the arm of the actuator. Operable. The system further includes a first raised rim formed around the second opening. The first raised rim is positioned in such a way that a liquid meniscus is formed along the outer surface of the liquid between the first raised rim and the arm of the actuator during operation of the arm of the actuator. ing.

Thus, spreading of the liquid outside the nozzle chamber through the second opening may be prevented. The actuator may preferably include a flat portion adjacent to the first raised rim and substantially parallel to and spaced from the substrate. The first raised rim may preferably include a flat portion and a substantially parallel edge. The first raised rim may include a raised lip.

[0027] The device may further include a second raised rim formed on the arm of the actuator adjacent to the first raised rim formed around the second opening. In this embodiment, the second raised rim may help prevent liquid from spreading out of the nozzle chamber through the second opening. The first raised rim may be formed from the deposition of a layer that also forms part of the arm of the actuator. At least one of the first and second raised rims may be formed from titanium nitride. A pit is formed adjacent the first raised rim, preferably to help reduce wicking.

According to a seventh aspect of the present invention, there is provided a liquid ejection device. A liquid ejection device is disposed in the nozzle chamber and ejects liquid from the nozzle chamber through an opening in one wall of the nozzle chamber when moved from the first state to the ejection state. A paddle and a liquid supply port arranged in such a way that the paddle is substantially closed by the paddle when in the first state. Such a nozzle chamber includes an internal protrusion on its wall structure that is aligned closely adjacent the rim of the paddle when the paddle is in the first state. In the spouted state, at least a portion of the paddle rim is spaced from the protrusion, thereby providing a liquid refill defined between the wall structure and that portion of the paddle rim. Form a channel.

[0029] The inner protrusion may have a stepped cross section. The paddles and internal protrusions are preferably formed in one deposition step. The internal protrusion may be formed using a deposition process with a lower aspect ratio compared to a high aspect ratio deposition process that forms the nozzle chamber wall structure. The paddle may be substantially flat.

[0030] Despite any other form that may fall within the scope of the invention, a preferred form of the invention will now be described, by way of example only, with reference to the accompanying drawings.

DESCRIPTION OF THE PREFERRED AND OTHER EMBODIMENTS In a preferred embodiment, a compact form of liquid ejection device is provided that utilizes an actuator that bends by heat to eject ink from a nozzle chamber.

First, the operation principle of the preferred embodiment will be described with reference to FIGS. FIG.
As shown in FIG. 1, an ink ejection device 1 is provided. The ink ejection device 1 includes a nozzle chamber 2 that is normally filled with ink and forms a meniscus 3 around an ink ejection nozzle 4 having a raised rim. The ink in the nozzle chamber 2 is supplied by the ink supply channel 5.

With the thermal actuator 7 firmly interconnected to the paddle 8 of the nozzle,
Ink is ejected from the nozzle chamber 2. The thermal actuator 7 includes two arms 10, 11, the lower arm 11 being interconnected to a current source for providing conduction heating of the lower arm 11. If it is desired to eject a drop from the nozzle chamber 2, the lower arm 11 is heated so that it expands rapidly with respect to the upper arm 10. This rapid expansion, in turn,
Paddle 8 moves rapidly upward in nozzle chamber 2. FIG. 2 shows this initial movement. The arm 8 moves upward, so that the pressure in the nozzle chamber 2 essentially rises, which in turn causes ink to flow out of the nozzle 4 and the meniscus 3 to swell. Next, the current to the heater 11 is turned off, and FIG.
, The paddle 8 starts to return to its original position. As a result, the pressure in the nozzle chamber 2 essentially decreases. Since the ink outside the rim 4 of the nozzle is urged forward, as a result, the meniscus is narrowed and divided, and the meniscus 3 and the bubble 13 are formed as shown in FIG. Bubbles 13 continue to advance forward onto the ink print media.

Importantly, the nozzle chamber includes an edge 15 in longitudinal section, which greatly increases the space 16 in the channel as the paddle 8 moves upward, as shown in FIG. By increasing the space 16 of the channel in this manner, ink is drawn through the channel 16 due to the surface tension effect of the meniscus 3 of the ink, and a substantial amount of ink can quickly flow into the nozzle chamber 2. The nozzle chamber profile allows the nozzle chamber to be quickly refilled, and the device eventually returns to the rest position, as previously shown in FIG.

The device 1 also includes a number of other important features. These are shown in Figure 1
A circular rim 18 as shown in FIG. A circular rim 18 is formed around the perimeter of the paddle 8 to substantially maximize the distance between the meniscus 3 shown in FIG. 3 and the paddle surface 8 while providing structural support for the paddle 8. I have. By maximizing this distance, the likelihood of the meniscus 3 contacting the paddle surface 8 and thereby affecting the operating characteristics is reduced. Further, as part of the manufacturing process, an ink spill lip 19 is provided to reduce the likelihood of ink wicking along the surface, eg, 20, thereby affecting the operating characteristics of the device 1. .

First, the operation principle of the thermal actuator 7 will be described with reference to FIGS. First, referring to FIG. 4, an actuator which is attached to the substrate 22 and bends by heat is shown. The actuator that bends by heat includes an arm 23 of the actuator, on both sides of which there are actuation arms 24,25. The two arms 24, 25
It is preferably formed from the same material so that it is thermally balanced with each other. Further, it is assumed that a pressure P acts on the surface of the arm 23 of the actuator.
If a pressure increase is desired, the lower arm 25 is heated, as shown in FIG.
The tensile stress between the upper arm 24 and the lower arm 25 is reduced. As a result, the resultant force acting on the arm 23 of the actuator is output, and as a result, the arm 23 of the actuator moves upward as a whole.

Unfortunately, in practice, it has been found that if the arms 24, 25 are too long, there is a risk that heating the arm 25 will result in a warped state as shown in FIG. This warped state reduces the operational effectiveness of the arm 23 of the actuator. The possibility of warping as shown in FIG. 6 can be substantially reduced by utilizing smaller, thermally bent arms 24,25. An apparatus modified in this way is shown in FIG. It has been found that heating the lower thermal arm 25 as shown in FIG. 8 causes the arm 23 of the actuator to bend upwards, essentially reducing the possibility of the system entering the warped state of FIG.

In the apparatus shown in FIG. 8, the operating parts 24 and 2 of the arm 23 of the actuator are used.
The portion 26 between 5 and 5 will be in a state of shear stress, which may result in a loss of operating efficiency in this embodiment. Furthermore, heat can quickly conduct from the arm 25 to the arm 24 as a result of the presence of the material 26. Further, the thermal arm 25 must be operated at a temperature suitable for operating the arm 23. The operating characteristics are thus limited by the characteristics of the part 26, for example the melting point.

FIG. 9 shows another type of actuator that bends due to heat. Such an actuator includes two arms 24, 25 and an arm 23 of the actuator, with a space or gap 28 between the arms. When one of the arms is heated, the arm 25 bends upward as before, as shown in FIG. The device of FIG. 10 has the advantage that the operating characteristics of the arms 24, 25, for example the temperature, need not necessarily be limited by the material used in the arm 23. Furthermore, the device of FIG. 10 does not induce a shear force in the arm 23, and is less likely to cause delamination during operation. These principles have been utilized in the thermally bent actuators of the apparatus of FIGS. 1-3 to provide a more energy efficient mode of operation.

In addition, a number of further refinements are made to provide a more efficient type of thermal actuator. Thermal actuators rely on conductive heating, and the equipment utilized in the preferred embodiment can be simplified schematically to material 30, as shown in FIG. Material 30 is interconnected to a substrate at a first end 31 and to a load at a second end 32. The arm 30 is heated by conduction and expands to exert a force on the load 32. Upon heating by conduction, the temperature profile will be approximately as shown in FIG. The two ends 31, 32 serve as "heat sinks" for their conductive heating, so the temperature profile is lower at each end and highest at the center. The operating characteristics of the arm 30 are determined by the melting point 35 in that the arm may not operate if the temperature at the center 36 exceeds the melting point 35. The graph of FIG. 12 illustrates a suboptimal result in that the arm 30 in FIG. 11 is not uniformly heated along its length.

As shown in FIG. 13, by deforming the arm 30 so that the heat sinks 38 and 39 are included in the central portion of the arm 30, a more favorable thermal profile as shown in FIG. 14 can be achieved. . The profile of FIG. 14 has been heated more uniformly over the length of the arm 30, which makes the overall operation more efficient.

Referring now to FIG. 15, further efficiency and reduced warpage can be achieved by providing a series of struts to couple the two actuator actuation arms 24, 25. Such an apparatus is shown schematically in FIG. In FIG. 15, a series of columns, eg, 40, 41, are provided to provide two arms 24, 25.
To prevent the warpage. Therefore, the lower arm 25
Heating increases the likelihood of bending upwards, so that the arm 23 of the actuator also bends upwards.

One type of detailed configuration of the inkjet printing MEMS device will be described below. In some of the figures, a 1 micron grid as shown in FIG. 17 is used as a frame of reference.

Steps 1 and 2. The starting material is a suitably processed and passivated (using silicon nitride) CMOS wafer 100 as shown in FIGS.

Step 3. As shown in FIGS. 19-21, a 1 micron spin-on photosensitive polyimide 102 is deposited and exposed through a mask 104 of FIG. 20 using ultraviolet light. Next, the polyimide 102 is developed. Since polyimide 102 is sacrificial, a wide range of other materials can be used. In the case of photosensitive polyimide, the processing is simplified because the steps of deposition, etching, and resist stripping are omitted.

Step 4. As shown in FIGS. 22 to 24, a titanium nitride 106 sputtered with a 0.2 micron magnetron is deposited at 300 ° C.
8 to perform etching. Thus, a layer including the actuator layer 105 and the paddle 107 is formed.

Step 5 As shown in FIGS. 25-27, a 1.5 micron photosensitive polyimide 110 is spun on and exposed through a mask 112 of FIG. 26 using ultraviolet light. Next, the polyimide 110 is developed. This thickness ultimately determines the gap 101 between the actuator and the compensating titanium nitride layer, thus affecting the amount of bending of the actuator. Regarding step 3, the use of a photosensitive polyimide simplifies the processing because the steps of deposition, etching, and resist stripping are omitted.

Step 6 As shown in FIGS. 28-30, a 0.05 micron conformal P
(Due to the relative dimensions of the various layers, not shown) ECVD silicon nitride (Si _x N _y H _z) to推積at 300 ° C.. Next, a 0.2 micron magnetron sputtered titanium nitride 116 is also deposited at 300 ° C. This TiN
116 is etched using the mask 119 of FIG. Next, this TiN11
The PECVD nitride is etched using 6 as a mask.

It is not important that the step coverage of TiN 116 is good. TiN1
The top 16 layers are not electrically connected and are used as purely mechanical components.

Step 7 As shown in FIGS. 31-33, a 6 micron photosensitive polyimide 118 is spun on and exposed through a mask 120 of FIG. 32 using ultraviolet light. Next, the polyimide 118 is developed. This thickness determines the height to the nozzle chamber roof. If this height exceeds a certain distance (determined by droplet splitting properties), the actual height is of little importance. However, this height should be limited to reduce stress and increase lithographic accuracy. Providing a 1 micron taper between the top and bottom of a 6 micron polyimide 118 is easy.

Step 8 As shown in FIGS. 34 and 36, 2 microns (polyimide 1
PECVD silicon nitride 122 is deposited at 300 ° C.
This fills the channels formed in the aforementioned PS polyimide layer 118 forming the nozzle chamber. No mask is used (FIG. 35).

Step 9 As shown in FIGS. 37-39, PECVD silicon nitride 122 is etched to a nominal depth of 1 micron using mask 124 of FIG. This is a simple timed etch since this etch depth is not critical and may vary up to ± 50%. This etching is performed on the rim 126 of the nozzle and the rim 1
28 are formed. These rims are used to lock the ink meniscus in place and prevent the ink from spreading.

Step 10. As shown in FIGS. 40-42, using the mask 130 of FIG. 41, the PECVD silicon nitride 122 is etched to a nominal depth of 1 micron and stops on the polyimide 118. The variation in the above two steps is 100
% Over-etching, and the manufacturing tolerance can be reduced. This etching forms the roof 132 of the nozzle chamber.

Step 11 As shown in FIGS. 43-45, a nominal 3 micron polyimide 134 is spun on as a protective layer for back etching (no mask—FIG. 44).

Step 12. As shown in FIGS. 46 to 48, the wafer 100 is
Wafer 1 to micron thickness (to reduce back-etching time)
A 3 micron resist (not shown) on backside 136 of 00 is applied to mask 1 of FIG.
Exposure through. The position is adjusted to the metal part 103 on the front side of the wafer 100. This alignment can be performed using an infrared microscope attachment to the wafer aligner.

Next, the wafer 100 is etched (from the back side 36) using a deep silicon etch “Bosch process” to a depth of 330 microns (allowing 10% overetching). This process is available on plasma etchers from Alcatel, Plasma Therm, and Surface Technology Systems. The chips are also diced by this etching, but the wafer is still held together by various layers of polyimide of 11 microns.

Step 13. As described with reference to FIGS. 49-51, the wafer 100 is turned over, placed in a tray, and the sacrificial polyimide layers 102, 110, 118,
All of 134 are etched in an oxygen plasma without a mask (FIG. 6).
0).

Step 14. As described with reference to FIGS. 52 to 54, a package is created by drilling a 0.5 mm hold on a standard package and bonding an ink hose (not shown) to the package. This ink hose is 0.5
A micron absolute filter should be included to prevent nozzle contamination from ink 121.

FIGS. 55-62 show various views of a preferred embodiment, some of which show embodiments in operation. Obviously, the large array 200 of printheads 202 can be configured simultaneously, as shown in FIGS. 63-56, which show views of various printhead arrays.

The currently disclosed ink jet printing technology is suitable for a potentially wide range of printing systems. These printing systems include color and monochrome office printers, short run digital printers, high speed digital printers, complementary printers for offset presses, low cost scan printers, high speed page width printers, and notebook computers with built in page width printers. Portable color and monochrome printers, color and monochrome copiers, color and monochrome facsimile, combined printers and facsimile and copiers, label printers, large format plotters, photocopiers, digital photo minilabs "
Printers, video printers, photo CD printers, portable printers for PDAs, wallpaper printers, indoor sign printers, outdoor billboard printers, fabric printers, camera printers, and an array of fault tolerant commercial printers.

Furthermore, the outlined MEMS principles have general applicability in the construction of MEMS devices.

It will be apparent to those skilled in the art that numerous modifications and / or variations may be made to the invention as set forth in the preferred embodiments without departing from the spirit or scope of the invention as broadly described. Will be understood. Accordingly, the preferred embodiments must be considered in all respects as illustrative and not restrictive.

[Brief description of the drawings]

FIG. 1 schematically illustrates the operation of a preferred embodiment.

FIG. 2 schematically illustrates the operation of the preferred embodiment.

FIG. 3 schematically illustrates the operation of the preferred embodiment.

FIG. 4 schematically shows a first thermal bending actuator.

FIG. 5 schematically shows a first thermal bending actuator.

FIG. 6 schematically shows a first thermal bending actuator.

FIG. 7 schematically shows a second thermal bending actuator.

FIG. 8 schematically illustrates a second thermal bending actuator.

FIG. 9 schematically illustrates a third thermal bending actuator.

FIG. 10 schematically illustrates a third thermal bending actuator.

FIG. 11 schematically shows a further thermal bending actuator.

FIG. 12 shows an exemplary graph of temperature with respect to distance for the apparatus of FIG.

FIG. 13 schematically shows a further thermal bending actuator.

FIG. 14 shows an exemplary graph of temperature with respect to distance for the apparatus of FIG.

FIG. 15 schematically illustrates a further thermal bending actuator.

FIG. 16 shows a side perspective view of a CMOS layer of the preferred embodiment.

FIG. 17 shows a 1 micron mask.

FIG. 18 shows a plan view of a portion of a CMOS layer.

FIG. 19 shows a side perspective view of a preferred embodiment having a sacrificial polyimide layer.

FIG. 20 shows a plan view of a sacrificial polyimide mask.

FIG. 21 illustrates a partial cross-sectional side view of a preferred embodiment having a sacrificial polyimide layer.

FIG. 22 shows a side perspective view of a preferred embodiment having a first level titanium nitride layer.

FIG. 23 shows a plan view of a first level titanium nitride mask.

FIG. 24 illustrates a partial cross-sectional side view of a preferred embodiment having a first level titanium nitride layer.

FIG. 25 shows a side perspective view of a preferred embodiment having a second level sacrificial polyimide layer.

FIG. 26 shows a plan view of a second level sacrificial polyimide mask.

FIG. 27 illustrates a partial cross-sectional side view of a preferred embodiment having a second level sacrificial polyimide layer.

FIG. 28 shows a side perspective view of a preferred embodiment having a second level titanium nitride layer.

FIG. 29 shows a plan view of a second level titanium nitride mask.

FIG. 30 illustrates a partial cross-sectional side view of a preferred embodiment having a second level titanium nitride layer.

FIG. 31 shows a side perspective view of a preferred embodiment having a third level sacrificial polyimide layer.

FIG. 32 shows a plan view of a third level sacrificial polyimide mask.

FIG. 33 illustrates a partial cross-sectional side view of a preferred embodiment having a third level sacrificial polyimide layer.

FIG. 34 shows a side perspective view of a preferred embodiment having a conformal PECVD SiNH layer.

FIG. 35 shows a plan view of a conformal PECVD SiNH mask.

FIG. 36 shows a partial cross-sectional side view of a preferred embodiment having a conformal PECVD SiNH layer.

FIG. 37 shows a side perspective view of a preferred embodiment having a conformal PECVD SiNH nozzle tip etch layer.

FIG. 38 shows a plan view of a conformal PECVD SiNH nozzle tip etching mask.

FIG. 39 shows a partial cross-sectional side view of a preferred embodiment having a conformal PECVD SiNH nozzle tip etch layer.

FIG. 40 shows a side perspective view of a preferred embodiment having a conformal PECVD SiNH nozzle roof etch layer.

FIG. 41 shows a plan view of a conformal PECVD SiNH nozzle roof etch mask.

FIG. 42 illustrates a partial cross-sectional side view of a preferred embodiment having a conformal PECVD SiNH nozzle roof etch layer.

FIG. 43 shows a side perspective view of a preferred embodiment having a sacrificial protective polyimide layer.

FIG. 44 shows a plan view of a sacrificial protection polyimide mask.

FIG. 45 illustrates a partial cross-sectional side view of a preferred embodiment having a sacrificial protective polyimide layer.

FIG. 46 shows a side perspective view of a preferred embodiment having a back etch layer.

FIG. 47 shows a plan view of a back etching mask.

FIG. 48 shows a side view of a partial cross section of a preferred embodiment having a back etch layer.

FIG. 49 shows a side perspective view of a preferred embodiment having a stripping sacrificial material layer.

FIG. 50 shows a plan view of a stripping sacrificial material mask.

FIG. 51 shows a partial cross-sectional side view of a preferred embodiment having a stripping sacrificial material layer.

FIG. 52 shows a side perspective view of a preferred embodiment having packaging, bonding, priming, and testing.

FIG. 53 shows a plan view of a mask for packaging, bonding, priming, and testing.

FIG. 54 illustrates a partial cross-sectional side view of a preferred embodiment having packaging, bonding, priming, and testing.

FIG. 55 shows a side perspective cross-sectional view of a preferred embodiment ejecting drops.

FIG. 56 shows a side perspective view of the preferred embodiment when in operation.

FIG. 57 shows a side perspective cross-sectional view of a preferred embodiment ejecting drops.

FIG. 58 shows a side view of a partial cross section of the preferred embodiment when returning.

FIG. 59 shows a plan view of the preferred embodiment.

FIG. 60 is an enlarged perspective view showing the arm and the nozzle chamber of the actuator as viewed from the side.

FIG. 61 is an enlarged side perspective view showing the rim of the paddle and the nozzle chamber of the actuator.

FIG. 62 is an enlarged perspective view showing a heater element of the actuator as viewed from the side.

FIG. 63 shows a plan view of an array of nozzles formed on a wafer.

FIG. 64 shows a perspective cross-sectional view from the side of an array of nozzles formed on a wafer.

FIG. 65 shows an enlarged perspective cross-sectional view from the side of an array of nozzles formed on a wafer.

──────────────────────────────────────────────────続 き Continued on the front page (31) Priority claim number PP 8688 (32) Priority date February 15, 1999 (Feb. 15, 1999) (33) Priority claim country Australia (AU) (31) Priority Claim number PP 8689 (32) Priority date February 15, 1999 (Feb. 15, 1999) (33) Priority claiming country Australia (AU) (31) Priority claim number PP 8690 (32) Priority date Heisei February 15, 1999 (Feb. 15, 1999) (33) Priority claiming country Australia (AU) (31) Priority claim number PP 8691 (32) Priority date February 15, 1999 (Feb. 15, 1999) 15) (33) Priority country Australia (AU) (81) Designated country EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC , NL, PT, SE), O A (BF, BJ, CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, KE, LS, MW, SD, SL, SZ, TZ, UG, ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AE, AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, CA, CH, CN, CR, CU, CZ, DE, DK, DM, EE, ES, FI, GB, GD, GE, GH, GM, HR, HU, ID, IL, IN, IS, JP , KE, KG, KP, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MA, MD, MG, MK, MN, MW, MX, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT, TZ, UA, U G, US, UZ, VN, YU, ZA, ZW

Claims (53)

[Claims] 1. A thermal actuator for a micro-electro-mechanical device, comprising: a support substrate, an actuator operating part, attached to the substrate at a first end and to the operating part at a second end. A first arm that is arranged to be heatable by conduction during use; a first arm attached to the support substrate at a first end and a working arm at a second end. A second arm mounted thereon, the second arm being spaced apart from the first arm, whereby the first and second arms define a gap therebetween. Wherein during use the first arm expands thermally when heated by conduction;
A thermal actuator arranged such that a force is applied to said actuating part. 2. The thermal actuator according to claim 1, wherein the actuator is arranged in such a way that a heating current can be applied to the first arm through the support substrate. 3. The thermal actuator according to claim 1, wherein the first and second arms are formed from substantially the same material. 4. The actuator according to claim 1, further comprising: depositing and etching a first layer to form the first arm; and depositing and etching a second layer to cover the first arm. Forming a sacrificial layer support structure, forming and etching a third layer to form the second arm, and etching the second layer to form the first arm and the second arm. Forming said gap between said arm and said arm. 5. The device of claim 1, wherein the first arm includes at the second end at least two elongated flexible strips interconnected by conduction.
5. The thermal actuator according to claim 4. 6. The thermal actuator according to claim 1, wherein the second arm includes at least two elongated flexible strips. 7. The thermal actuator according to claim 1, wherein the operating portion includes a paddle structure. 8. The method according to claim 1, wherein said first arm is formed of titanium nitride.
The thermal actuator according to claim 1. 9. A paddle for ejecting liquid from within a nozzle chamber through a liquid ejection nozzle defined on one wall of the nozzle chamber, the paddle being opposed to and spaced from the nozzle during use. A first portion configured to provide a disposed substantially planar plunger surface; and a structural portion formed on the plunger surface around the first portion to provide structural support for the first portion. A second portion, whereby during use the second portion acts as a spacer while the plunger is activated to eject liquid through the nozzle,
A paddle that prevents the plunger surface from touching the nozzle. 10. The second portion is configured to define a wall structure around the central portion with the central portion of the plunger surface substantially aligned with the nozzle during use. 9. The paddle according to item 9. 11. The paddle according to claim 10, wherein the central portion has the same size as the nozzle. 12. The first portion has a circular outer periphery, and the second portion has
A paddle according to any one of claims 9 to 11, including an annulus around the outer periphery of the paddle. 13. The wall structure according to claim 1, wherein a lower portion is partially cut.
Paddle described in 0. 14. The paddle is formed by depositing and etching a first layer to form the first portion, and depositing and etching a second layer to form a part of the first portion. Forming a sacrificial layer structure on top of the above, and depositing and etching a third layer to form the second portion, and etching the sacrificial layer to partially lower the second portion. 14. The paddle according to claim 13, wherein the paddle is formed by cutting. 15. A mechanical actuator for a micro-mechanical or micro-electro-mechanical device, comprising: a support substrate, an actuating part, attached to said substrate at a first end thereof and said actuation at a second end. A first arm attached to the portion, the first arm being arranged to be heatable by conduction during use, attached to the support substrate at a first end, and at a second end A second arm attached to the actuating portion, the second arm being spaced from the first arm such that the first and second arms define a gap therebetween.
At least one rigid member interconnects the first arm and the second arm between the first end and the second end thereof, wherein during use, An actuator, wherein the first arm is thermally expanded, whereby the actuator is arranged to apply a force to the actuator. 16. The first arm comprises: a first main body formed between the first end and the second end of the first arm; and a first main body formed on the first arm. 16. The actuator of claim 15, comprising at least one tab body connected, wherein the first of the at least one rigid member interconnects the tab with the second arm. 17. The second arm, comprising: a second main body formed between the first end and the second end of the second arm; and a second main body formed between the second arm and the second main body. Connected to at least one corresponding tab body, wherein the first one of the at least one rigid member is the first member.
17. The actuator of claim 16, wherein said corresponding two tabs of a second arm are interconnected. 18. The actuator of claim 16 or 17, wherein the tab body is connected to the first main body through a first thinned neck. 19. The actuator according to claim 17, wherein the corresponding tab body is connected to the second main body through a second thinned neck. 20. The first arm, wherein the first arm is heatable by conduction, causing the first arm to thermally expand with respect to the second arm during use, thereby causing the first arm to expand. 20. An actuator according to any one of claims 15 to 19, wherein the actuator comprises a conductive layer adapted to apply a force to the working part. 21. The method according to claim 15, wherein the first and second arms are substantially parallel, and the rigid member is substantially perpendicular to the first and second arms. Actuator. 22. An actuator according to any one of claims 15 to 21 arranged in such a way that, in use, current can be supplied to the conductive layer through the support substrate. 23. The actuator according to claim 15, wherein the first and second arms are formed from substantially the same material. 24. Depositing and etching a first layer to form the first arm; depositing and etching a second layer to support a sacrificial layer above the first arm. Forming a structure; depositing and etching a third layer to form the second arm; and etching the sacrificial layer to form the first arm and the second arm. The actuator according to any one of claims 15 to 23, wherein the actuator is manufactured by: forming the gap therebetween. 25. The first arm includes at its second end two first elongated flexible strips interconnected by conduction.
The actuator according to any one of claims 24. 26. The actuator according to any one of claims 15 to 25, wherein the second arm comprises two second elongated flexible strips. 27. The actuator according to claim 15, wherein the operating portion includes a paddle structure. 28. The method of claim 15, wherein the first arm is formed from titanium nitride.
28. The actuator according to any one of -27. 29. The second arm is formed from titanium nitride.
29. The actuator according to any one of -28. 30. A thermal actuator for a micro-mechanical or micro-electro-mechanical device, comprising: a support substrate, an actuator extension, attached to the substrate at a first end thereof, and the extension at a second end. A first arm attached to the portion, the first arm being arranged to be heatable by conduction during use, attached to the support substrate at a first end, and at a second end A second arm attached to the extension, the second arm being spaced apart from the first arm, wherein during use the first arm thermally expands; Whereby the actuator is arranged to apply a force to the extension, wherein the first arm is used in such a way that maximum heating of the first arm occurs during use Actuator comprising at least one heat sink element at the heating point. 31. The actuator of claim 30, wherein the heat sink element is located substantially at the center of the first arm. 32. The actuator according to claim 30, wherein the heat sink element is arranged to interconnect the first arm and the second arm. 33. The actuator according to any one of claims 30 to 32, wherein the heat sink element includes at least one tab body connected to a main body of the first arm. 34. The actuator of claim 33, wherein the tab body is connected to the main body through a first thinned neck. 35. The actuator according to any one of claims 30 to 34, wherein the first arm includes a conductive layer by which the first arm can be heated by conduction. 36. The actuator of claim 35, wherein the actuator is arranged in such a way that current can be supplied to the conductive layer through the support substrate. 37. The actuator according to claim 30, wherein the first and second arms are formed from substantially the same material. 38. The actuator according to claim 30, wherein the extension includes a paddle structure. 39. The first arm is formed from titanium nitride.
39. The actuator according to any one of -38. 40. The second arm is formed from titanium nitride.
40. The actuator according to any one of -39. 41. A nozzle chamber for ejecting a liquid having a first opening in one wall thereof and a second opening in the wall through which an actuator arm extends. The arm of the actuator is attached to a substrate disposed outside the nozzle chamber and connected to a paddle inside the nozzle chamber, the paddle dispensing the liquid through the arm of the actuator to the first position. A nozzle chamber operable to squirt through an opening of a first raised rim formed around said second opening, wherein during operation of an arm of said actuator, A liquid meniscus is formed between the first raised rim and the arm of the actuator along an outer surface of the liquid such that a meniscus of liquid is formed. Is, liquid ejecting device including a first raised rim. 42. The device of claim 41, wherein the actuator includes a flat portion adjacent to the first raised rim and substantially parallel to and spaced from the substrate. 43. The device of claim 42, wherein the first raised rim includes an edge substantially parallel to the flat portion. 44. The device according to any one of claims 41 to 43, wherein the first raised rim includes a raised lip. 45. The actuator according to claim 45, further comprising a second raised rim formed on the arm of the actuator adjacent to the first raised rim formed around the second opening. 45. The device according to any one of 41 to 44. 46. The device according to any one of claims 41 to 45, wherein the first raised rim is formed from the deposition of a layer that also forms part of the arm of the actuator. 47. The device of any one of claims 41-46, wherein at least one of said first and second raised rims is formed from titanium nitride. 48. The device of any one of claims 41-47, wherein a pit is formed adjacent to the first raised rim to help reduce wicking. 49. A nozzle chamber, disposed in the nozzle chamber, wherein the nozzle chamber is moved from a first state to a jetting state.
An ejection paddle for ejecting liquid from said nozzle chamber through an opening in one wall of said nozzle chamber; and arranged in such a way that said paddle is substantially closed by said paddle when said paddle is in said first state. A liquid supply port, the nozzle chamber having an interior projection on its wall structure aligned closely adjacent a rim of the paddle when the paddle is in the first state. Wherein, in the jetting state, at least a portion of the rim of the paddle is spaced from the protrusion, whereby the portion of the rim of the paddle and the wall structure is provided. A liquid ejection device forming a liquid refill channel defined there between. 50. The device of claim 49, wherein the internal protrusion is stepped in cross section. 51. The device according to claim 49 or 50, wherein the paddle and the internal protrusion are formed in one deposition step. 52. The internal projection is formed using a deposition process having a lower aspect ratio than a high aspect ratio deposition process for forming the wall structure of the nozzle chamber. A device according to any one of the preceding claims. 53. The device according to any one of claims 49 to 52, wherein the paddle is substantially flat.