JP6749879B2 - Formal print bar - Google Patents

Description

Each printhead die in an inkjet pen or printbar contains fine channels that propagate ink to the ejection chamber. Ink is dispensed from an ink supply to the channels of the printhead die via passages in a structure that supports the printhead die(s) on the inkjet pen or the printbar.

For example, it is desirable to reduce the size of each printhead die in order to reduce the cost of the printhead die and thus the cost of the inkjet pen or printbar. However, if a smaller printhead die is used, modifications need to be made to the larger structure containing the channels that support the printhead die and supply ink to the printhead die.

Figure 3 shows a first embodiment (1/2) of a novel moldable fluid structure with microdevices embedded within the molded body, the molded body having a direct fluid path to the microdevice. Figure 2 shows a first embodiment (2/2) of a novel moldable fluid structure with microdevices embedded within the mold, the mold having a direct fluid path to the microdevice. Figure 2 shows a second embodiment (1/2) of a novel molded fluid structure with microdevices embedded within the molding, the molding having a direct fluid path to the microdevice. Figure 7 shows a second embodiment (2/2) of a novel molded fluidic structure with a microdevice embedded within the compact, the compact having a direct fluid path to the microdevice. Figure 3 shows a third embodiment (1/2) of a novel molded fluid structure with microdevices embedded within the molding, the molding having a direct fluid path to the microdevice. Figure 3 shows a third embodiment (2/2) of a novel molded fluid structure with a microdevice embedded in the compact, the compact having a direct fluid path to the microdevice. Figure 4 shows a fourth embodiment (1/2) of a novel moldable fluid structure with microdevices embedded within the mold, the mold having a direct fluid path to the microdevice. Figure 4 shows a fourth embodiment (2/2) of a novel moldable fluid structure with a microdevice embedded in the molding, the molding having a direct fluid path to the microdevice. FIG. 9 is a block diagram illustrating a fluid system implementing a novel fluid structure (such as one of the embodiments shown in FIGS. 1-8). FIG. 3 is a block diagram illustrating an inkjet printer that implements an example of a novel fluid structure for a printhead in a substrate wide printbar. 11 illustrates an inkjet printbar embodying an example of a novel fluid structure for a printhead die such as used in the printer of FIG. 11 illustrates an inkjet printbar embodying an example of a novel fluid structure for a printhead die such as used in the printer of FIG. 11 illustrates an inkjet printbar embodying an example of a novel fluid structure for a printhead die such as used in the printer of FIG. 11 illustrates an inkjet printbar embodying an example of a novel fluid structure for a printhead die such as used in the printer of FIG. 11 illustrates an inkjet printbar embodying an example of a novel fluid structure for a printhead die such as used in the printer of FIG. 11 illustrates an inkjet printbar embodying an example of a novel fluid structure for a printhead die such as used in the printer of FIG. FIG. 6 is a cross-sectional view showing an example (1/5) of a process for producing a fluid structure of a novel printhead die. FIG. 6 is a cross-sectional view showing an example (2/5) of a process for producing a fluid structure of a novel printhead die. FIG. 6 is a cross-sectional view showing an example (3/5) of a process for producing a fluid structure of a novel printhead die. FIG. 6 is a cross-sectional view showing an example (4/5) of a process for producing a fluid structure of a novel printhead die. FIG. 6 is a cross-sectional view showing an example (5/5) of a process for making a novel printhead die fluidic structure. 22 is a flowchart of the process shown in FIGS. 17 to 21. FIG. 17 is a perspective view showing an example of a wafer level process for making a novel inkjet printbar such as the printbars shown in FIGS. 11-16. FIG. 17 is a perspective view showing an example of a wafer level process for making a novel inkjet printbar such as the printbars shown in FIGS. 11-16. FIG. 17 is a perspective view showing an example of a wafer level process for making a novel inkjet printbar such as the printbars shown in FIGS. 11-16. FIG. 17 is a perspective view showing an example of a wafer level process for making a novel inkjet printbar such as the printbars shown in FIGS. 11-16. FIG. 17 is a perspective view showing an example of a wafer level process for making a novel inkjet printbar such as the printbars shown in FIGS. 11-16. 24 shows details of FIG. 23. 7 illustrates another example of a novel fluid structure for a printhead die. 7 illustrates another example of a novel fluid structure for a printhead die. 7 illustrates another example of a novel fluid structure for a printhead die.

In all the drawings, the same reference numerals indicate the same or similar elements. The drawings are not necessarily to scale. The relative sizes of some of the elements have been exaggerated to more clearly show the example shown.

Inkjet printers using substrate width printbar assemblies have been developed to help improve printing speed and reduce printing costs. A conventional substrate width printbar assembly includes a plurality of portions that propagate printing fluid from a source of printing fluid to a small printhead die from which the printing fluid is jetted onto paper or other print substrate. .. Reducing the size and spacing of the printhead dies continues to be important for cost savings, and delivery of printing fluid from larger ink supply elements to much smaller, more closely spaced dies is complicated. It requires different flow channel structures and manufacturing processes, which can actually increase costs.

New fluid structures have been developed that allow the use of smaller printhead dies and smaller die circuits that contribute to cost savings in substrate width inkjet printers. A printbar embodying an example of the novel fluid structure includes a plurality of printhead dies molded into an elongated monolithic body of moldable material. A plurality of printing fluid channels molded within the body directly propagates printing fluid to a plurality of printing fluid passages in each die. The molded body effectively enlarges the size of each die to make external fluid connections and to attach the die to other structures, thereby allowing the use of smaller die. It will be possible. The printhead die and printing fluid channels can be molded at the wafer level to form a novel composite printhead wafer containing printing fluid channels, which allows printing fluid channels to be formed on a silicon substrate. There is no need to form and thinner dies can be used.

The novel fluid structure is not limited to printbars or other types of printhead structures for inkjet printing, but can be implemented in other devices and for other fluid applications. Thus, in one embodiment, the novel structure comprises a microdevice embedded within a shaped body, the shaped body comprising a channel or a channel for direct fluid flow into or onto the microdevice. It has other channels. The microdevice can be, for example, an electronic device, a mechanical device, or a MEMS (Microelectromechanical system) device. The fluid flow can be a flow of cooling fluid into or on the microdevice or into a printhead or other microdevice that dispenses the fluid.

The foregoing and other examples illustrated and described below illustrate, but do not limit, the invention, which is defined by the claims.

As used herein, "microdevice" means a device having one or more outside dimensions of 30 mm or less, "thin" means a thickness of 650 μm or less, and "sliver". Refers to a thin microdevice having a length/width (L/W) ratio of at least 3, and "printhead" and "printhead die" refer to an ink jet printer or to dispense fluid from one or more openings. Means part of an inkjet type dispenser. The printhead includes one or more printhead dies. "Printhead" and "printhead die" are not limited to printing with ink or other printing fluids, but also include inkjet-type dispensing of other fluids and/or for applications other than printing.

1 and 2 are a front view and a plan view showing an embodiment of a novel fluid structure 10. Referring to FIGS. 1 and 2, structure 10 includes a microdevice 12 molded within an integral body 14 of plastic or other moldable material. The molded body 14 is also referred to as a molded body 14 in this document. For example, the micro device 12 can be an electronic device, a mechanical device, or a MEMS device. A channel or other suitable flow channel 16 is molded in the body 14 in communication with the microdevice 12 so that fluid in the channel 16 flows directly into the device 12 and/or to the device 12. Is possible. In this embodiment, the channels 16 are connected to fluid passageways 18 within the microdevice 12 and are exposed to the exterior surface 20 of the microdevice 12.

In another embodiment, shown in FIGS. 3 and 4, the channels 16 in the molded body 14 may be air or other fluid along the outer surface 20 of the microdevice 12 (eg, for cooling the microdevice 12). To allow it to flow. Also in this embodiment, signal traces or other conductors 22 that are connected to the device 12 at electrical terminals 24 are molded into the molded body 14. In another embodiment, shown in FIGS. 5 and 6, microdevice 12 is molded within body 14 and has an exposed surface 26 opposite channel 16. In yet another embodiment shown in FIGS. 7 and 8, microdevices 12A, 12B are molded within body 14 and have fluid channels 16A, 16B. In this embodiment, the fluid channel 16A contacts the edge of the outer device 12A and the fluid channel 16B contacts the bottom of the inner device 12B.

FIG. 9 is a block diagram illustrating a system 28 in which a novel fluid structure 10 (eg, one of the fluid structures 10 shown in FIGS. 1-8) has been implemented. With reference to FIG. 9, the system 28 includes a fluid source 30 operably connected to a fluid transfer means 32 configured to transfer fluid to the flow path 16 in the fluidic structure 10. The fluid source 30 includes, for example, atmospheric air as a source of air for cooling the electronic microdevice 12, or a printing fluid source for the printhead microdevice 12. The fluid transfer means 32 represents a pump, a fan, gravity, or any other suitable mechanism for transferring fluid from the fluid source 30 to the fluid structure 10.

FIG. 10 is a block diagram illustrating an inkjet printer 34 that embodies an example of the novel fluid structure 10 in a substrate width print bar 36. Referring to FIG. 10, a printer 34 includes a print bar 36 that spans the entire width of a print substrate 38, flow control means 40 associated with the print bar 36, a substrate transport mechanism 42, an ink or other printing fluid source 44, and a printer. Includes controller 46. The controller 46 represents the electronics and components necessary to control programming, the processor(s) and associated memory, and operable elements of the printer 10. The print bar 36 includes a plurality of print heads 37 in an array for distributing printing fluid on a sheet of paper, continuous web of paper, or other print substrate 38. As will be described in more detail below, each printhead 37 includes one or more printhead dies in one molding body and has channels 16 that directly supply printing fluid to the one or more printhead dies. There is. Each printhead die receives a printing fluid from a fluid supply 44 through flow control means 40 and a channel through channel 16 in printbar 36.

11-16 illustrate an inkjet printbar 36 (e.g., that can be used in the printer 34 shown in FIG. 10) that implements one example of the novel fluid structure 10. Referring first to the plan view of FIG. 11, a plurality of print heads 37 are embedded within an elongated integral molding 14 and are arranged in a staggered configuration within a plurality of rows 48, generally end to end. Of printheads in the row overlap the other printheads in the row. Although a plurality of staggered printheads 37 in four rows 48 are shown (eg, for printing four different colors), other suitable configurations can be used.

12 is a sectional view taken along line 12-12 of FIG. FIGS. 13-15 are detailed views of FIG. 12, and FIG. 16 is a plan view showing a layout of some of the features of the printhead die fluidic structure 10 of FIGS. 12-14. Referring to FIGS. 11-15, in the illustrated example, each printhead 37 includes a pair of printhead dies 12, each printhead die 12 having two rows of ejection chambers 50 and corresponding orifices 52. The printing fluid is ejected from the chamber 50 through the orifice 52. Each channel 16 in the molded body 14 supplies printing fluid to one printhead die 12. Other suitable configurations of printhead 37 can also be implemented. For example, it is possible to use more or less printhead dies 12 with more or less ejection chambers 50 and channels 16. (Although print bar 36 and print head 37 are facing upwards in FIGS. 12-15, print bar 36 and print head 37 are typically mounted in a printer as shown in the block diagram of FIG. Facing down.)
Printing fluid flows into each ejection chamber 50 from a manifold 54 extending longitudinally along each die 12 between the two rows of ejection chambers 50. Printing fluid is supplied into the manifold 54 via a plurality of ports 56 connected to the printing fluid supply channel 16 at the die surface 20. The printing fluid supply channel 16 is substantially wider than the printing fluid port 56, as shown, to allow for greater loosely spaced flow in the flow control means or other portion for propagating the printing fluid within the print bar 36. Propagating printing fluid from the channels to smaller, closely spaced printing fluid ports 56 in the printhead die 12. As such, the printing fluid supply channels 16 can help reduce or eliminate the need for separate "fan-out" and other fluid routing structures in conventional printheads. is there. Further, exposing a large area of the printhead die surface 20 directly to the channels 16 as shown allows the printing fluid in the channels 16 to cool the die 12 during printing.

An idealized representation of the printhead die 12 in FIGS. 11-15 is three layers 58, 60, 62, which reveal the ejection chamber 50, orifice 52, manifold 54, and port 56. It's just for convenience. The actual inkjet printhead die 12 is typically a complex integrated circuit (IC) structure formed on a silicon substrate 58 and has multiple layers and elements not shown in FIGS. 11-15. Will be things. For example, a thermal or piezoelectric ejection element formed on the substrate 58 in each ejection chamber 50 is driven to eject a droplet or stream of ink or other printing fluid from the orifice 52.

The molded fluid structure 10 allows the use of long, narrow and very thin printhead dies 12. For example, it has been found that a 100 μm thick printhead die 12 having a length of about 26 mm and a width of about 500 μm can be molded into a 500 μm thick body 14 to replace a conventional 500 μm thick silicon printhead die. ing. Not only is it cheaper and easier to mold the channels 16 in the body 14 but also to form the printing fluid ports 56 in the thinner die 12 as compared to forming the supply channels in the silicon substrate. Is cheaper and easier. For example, the ports 56 in the 100 μm thick printhead die 12 can be formed by dry etching or other suitable micromachining techniques that are not practical for thicker substrates. Proper printing by micromachining a highly dense array of straight or slightly tapered through-ports 56 in a thin silicon, glass, or other substrate 58, rather than conventional groove formation. It is possible to leave a stronger substrate while still providing fluid flow. The tapered port 56 helps move bubbles from within the manifold 54 and out of the ejection chamber 50, eg, formed in an integral or multi-layered orifice plate 60/62 applied to the substrate 58. Becomes Current die handling equipment and microdevice molding tools and techniques can be applied to mold dies 12 with length/width ratios up to 150 as thin as 50 μm, and narrow channels 16 as narrow as 30 μm. Expected to be possible. The molded body 14 also provides an effective and inexpensive structure capable of supporting multiple rows of such strips of die within a single, unitary body.

17-21 show an example of a process for creating a novel printhead fluid structure 10. FIG. 22 is a flow chart of the process shown in FIGS. Referring to FIG. 17, the flexible circuit 64 having the conductive traces 22 and the protective layer 66 is laminated onto the carrier 68 using heat dissipation tape 70, or otherwise applied to the carrier 68 (FIG. 22). Step 102). As shown in FIGS. 18 and 19, the printhead die 12 is positioned orifice side down on the carrier 68 in the opening 72 (step 104 in FIG. 22) and the conductors 22 are electrically connected to the electrical terminals 24 on the die 12. (Step 106 in FIG. 22). In FIG. 20, the molding tool 74 forms channels 16 in the molding 14 around the printhead die 12 (step 108 in FIG. 22). In some applications, tapered channel 16 is desirable to facilitate removal of molding tool 74 and/or increase fanout. After molding, the printhead fluid structure 10 is removed from the carrier 68 (step 110 in FIG. 22) to form the finished part shown in FIG. 21, in which the conductor 22 is covered by the layer 66 and the molded body. Surrounded by 14. In the transfer molding process as shown in FIG. 20, channels 16 are molded into body 14. In other fabrication processes, it may be desirable to form the channels 16 after molding the body 14 around the printhead die 12.

While molding a single printhead die 12 and a single channel 16 is shown in FIGS. 17-21, it is possible to simultaneously mold multiple printhead dies and multiple printing fluid channels at the wafer level. is there. 23-28 show an example of a wafer level process for making the print bar 36. Referring to FIG. 23, the printhead 37 is placed on a glass or other suitable carrier wafer 68 in a predetermined pattern of printbars. (A "wafer" is used to indicate a round substrate, while a "panel" is sometimes used to indicate a rectangular substrate, but as used herein, "wafer" refers to any shape. The printhead 37 typically includes first applying or forming a predetermined pattern of conductors 22 and die openings 72, as described above with reference to step 102 of FIGS. It will be arranged with respect to the carrier 68.

In the embodiment shown in FIG. 23, five sets of dies 78 each having four rows of print heads 37 are mounted on carrier wafer 66 to form five print bars. For example, a substrate width printbar with four rows of printheads 37 for letter or A4 size substrates would have a length of about 230 mm and a width of about 16 mm. Therefore, the five sets of dies 78 can be arranged on a single 270 mm×90 mm carrier wafer 66, as shown in FIG. In the illustrated embodiment, a series of conductors 22 extend to bond pads 23 near the edges of each row of printhead 37. The conductors 22 and bond pads 23 can be seen more clearly in the details of FIG. (Conductive signal traces to each of the plurality of ejection chambers or groups of ejection chambers, such as conductor 22 in FIG. 21, have been omitted so as not to interfere with other structural features.)
FIG. 24 is an enlarged sectional view showing a section 24-24 of the set of four print heads 37 in FIG. Cross hatching is omitted for clarity. 23 and 24 show the wafer structure in the manufacturing process after steps 102-112 of FIG. 23 are completed. 25 shows the cross section of FIG. 24 after the molding step 114 in which the body 14 having the channels 16 is molded around the printhead die 12 has been performed in FIG. The individual printbar stripes 78 are divided (FIG. 26) and removed from the carrier 68 (FIG. 27) to form five separate printbars 36 (step 116 of FIG. 23). Although any suitable molding technique can be used, as a result of testing, wafer level molding tools and techniques currently used for packaging semiconductor devices are shown in FIGS. 21 and 27. It has been suggested that it can be cost-effectively applied to the fabrication of a fluid structure 10 of a different printhead die.

If a stiffer (or at least less flexible) printbar 36 is desired to hold the printhead die 12, then a stiffer molding 14 can be used. If a flexible printbar 36 is desired, for example if another support structure rigidly holds the printbar in a single plane, or if a non-planar printbar configuration is desired, then a lower stiffness may be used. It is possible to use shaped bodies 14. It is also envisioned that the molded body 14 will typically be molded as an integral part, but the body 14 can be molded as more than one part.

29-31 illustrate another embodiment of the novel fluid structure 10 for the printhead die 12. In such an embodiment, the channels 16 are molded into the body 14 along both sides of the printhead die 12 using, for example, a transfer molding process as described above with respect to FIGS. Printing fluid flows laterally from channel 16 through port 56 to each ejection chamber 50. In the embodiment of FIG. 30, the orifice plate 62 is applied to close the channel 16 after molding the body 14. In the embodiment of FIG. 31, a cover 80 is formed on the orifice plate 62 to close the channel 16. Although a separate cover 80 is shown that partially defines the channel 16, it is also possible to use a one-piece cover 80 molded within the body 14.

As initially mentioned herein, the illustrated and described embodiments are illustrative of the invention and not limiting thereof. Different examples are also feasible. Therefore, the above description should not be construed as limiting the scope of the invention, which is defined by the appended claims.

Below, the exemplary embodiment which consists of a combination of various structural requirements of this invention is shown.
1. A printbar comprising a plurality of printhead dies molded within an elongated, unitary body, the plurality of printhead dies being disposed substantially end-to-end over a length of the body, A printbar wherein the body has a channel therein, through which fluid can pass directly to the die.
2. The printbar of claim 1, wherein each of the plurality of printhead dies comprises a thin die.
3. The print bar according to item 2 above, wherein each of the plurality of thin dies comprises an elongated slice.
4. Each of a plurality of said strips of die,
A plurality of holes connected to the channel, wherein the printing fluid is allowed to flow directly from the channel to the plurality of holes;
A manifold connected to the plurality of holes, wherein the printing fluid is allowed to flow directly from the plurality of holes to the manifold;
4. A plurality of ejection chambers connected to the manifold, the plurality of ejection chambers allowing the printing fluid to flow from the manifold to the plurality of ejection chambers. Print bar.
5. Each of the plurality of holes is tapered from a wide portion of the channel to a narrow portion of the manifold,
The channel is molded within the body and is tapered from a wide portion remote from the plurality of holes to a narrow portion of the plurality of holes;
The print bar according to item 4 above.
6. The plurality of strips of dies are arranged in rows in a staggered configuration over the length of the body, and the plurality of strips of dies in each row are of other strips in the row. It overlaps with the die,
The channels include a plurality of channels, each channel allowing fluid to pass directly to one or more of the plurality of die of strips;
The print bar according to item 3 above.
7. Each of the plurality of thin strip dies comprises:
A front surface having an orifice through which fluid can be dispensed from a die of the strips;
A back surface opposite to the front surface,
Including a side surface between the front surface and the back surface,
A channel is disposed along the at least one side of each of the plurality of elongated laminae,
The print bar according to item 6 above.
8. Each of the plurality of thin strip dies comprises:
A front surface having an orifice through which fluid can be dispensed from a die of the strips;
A back surface opposite to the front surface,
Including a side surface between the front surface and the back surface,
A channel is disposed along the back surface of each of the plurality of elongated dies.
The print bar according to item 6 above.
9. 7. The printbar of item 6 above, wherein the monolithic body supports the plurality of strip dies in a single plane.
Ten. A printbar having a body molded around a plurality of thin printhead dies, the molded body having a plurality of channels, the plurality of printheads being provided through the plurality of channels. Fluid is allowed to pass directly into the die, and the plurality of printhead dies are arranged in a plurality of rows in a generally staggered configuration, with the plurality of printhead dies in each row. A printbar in which a printhead die overlaps another printhead die in the row.
11. 11. The printbar of item 10, wherein the body comprises a one-piece body and supports the plurality of printhead dies within the body in a single plane.
12. Each of the plurality of printhead dies includes an electrical terminal, the printbar further comprises a plurality of conductors connected to the plurality of terminals, and the body is molded around the conductors and the terminals. The print bar according to item 10 above.
13. A plurality of strips of printhead dies, each of the plurality of strips of printhead dies enabling a plurality of ejection chambers and a plurality of fluid passages through the plurality of ejection chambers. And a front face having an orifice capable of ejecting fluid from the ejection chamber, and a back face opposite to the front face, the print head die comprising a plurality of thin strips,
A molded body for partially encapsulating a printhead die comprising the plurality of strips, wherein a plurality of channels in the body are directly connected to the printhead die comprising the plurality of strips. It has a print bar.
14. 15. The print bar according to item 14 above, wherein the plurality of channels are molded in the molded body.
15. A printbar having a plurality of thin printhead dies embedded within a one-piece mold, the plurality of channels allowing the mold to directly pass fluid to the plurality of thin printhead dies. Including a print bar.

Claims (11)

What is claimed is: 1. A fluid structure comprising a microdevice formed of an elongated slice formed in a molded body without using an adhesive , wherein a channel is formed inside the molded body, and a fluid is passed through the channel. A fluid structure that is capable of flowing directly into a microdevice consisting of, wherein the microdevice consisting of the strip comprises a channel directly connected to the channel. 2. The channel of claim 1, wherein the channel is exposed to an outer surface of the strip of microdevices and the channel is connected to the channel at the outer surface of the strip of microdevices. The fluid structure described. 3. The fluid channel has a fluid port connected to the channel at the outer surface of the strip of microdevices, the channel being wider than the fluid port. The fluid structure according to. The fluid structure according to any one of claims 1 to 3, wherein the flow path is tapered so as to become narrow in a direction in which the fluid flows. The fluid structure according to any one of claims 1 to 4, wherein the channel is tapered so as to become narrower toward the flow channel. The strip-shaped microdevice comprises a single strip-shaped printhead die,
6. The printhead die comprising the strips includes electrical terminals, and the molded body includes a conductor connected to the electrical terminals and embedded in the molded body. The fluid structure described. The strip microdevice comprises a plurality of strip printhead dies,
6. The printhead die of each of the plurality of strips includes an electrical terminal, and the molded body includes a conductor connected to the electrical terminal and embedded in the molded body. The fluid structure according to item 1. 8. The method of claim 7, wherein the channels include a plurality of channels, through which fluid can flow directly to at least one of the plurality of strips of printhead dies. Fluid structure. 9. A fluid structure according to any one of claims 1-8, wherein the channel comprises an open channel exposed to an outer surface of the elongated microdevice. The microdevice of strips includes an electronic or microelectromechanical device including electrical terminals, and the molded body further includes a conductor connected to the electrical terminals and embedded in the molded body. The fluid structure according to any one of claims 1 to 9. A microdevice consisting of the strip,
A silicon substrate including a plurality of ports directly and fluidly connected to the channel;
A first orifice plate disposed on the silicon substrate, the first orifice plate including a manifold having a plurality of chambers fluidly connected to the plurality of ports of the silicon substrate; ,
A second orifice plate disposed on the first orifice plate, the second orifice plate including a plurality of orifices each fluidly connected to the plurality of chambers of the first orifice plate. The fluid structure according to any one of claims 1 to 10, further comprising a plate.

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