WO2021183104A1

WO2021183104A1 - Fluidic die with adjacent and orthogonal bond pad regions

Info

Publication number: WO2021183104A1
Application number: PCT/US2020/021705
Authority: WO
Inventors: Eric Thomas MARTIN; Gary G. Lutnesky; James R. Przybyla
Original assignee: Hewlett-Packard Development Company, L.P.
Priority date: 2020-03-09
Filing date: 2020-03-09
Publication date: 2021-09-16

Abstract

In one example in accordance with the present disclosure, a fluidic die is described. The fluidic die includes a substrate and fluid actuators to displace a fluid, the fluid actuators being disposed on the substrate. The fluidic die also includes a first bond pad region disposed along a first edge of the substrate and a second bond pad region disposed along a second edge of the substrate. The second edge is adjacent and orthogonal to the first edge.

Description

FLUIDIC DIE WITH ADJACENT AND ORTHOGONAL BOND PAD REGIONS

BACKGROUND

[0001] A fluidic die is a component of a fluidic system. The fluidic die includes components that manipulate fluid flowing through the system. For example, a fluidic ejection die, which is an example of a fluidic die, includes a number of nozzles that eject fluid onto a surface. The same or a different fluidic die may also include non-ejecting fluid actuators such as micro-recirculation pumps that move fluid through the fluidic die. Using these nozzles and pumps, fluid, such as ink and fusing agent among others, is ejected or moved.

BRIEF DESCRIPTION OF THE DRAWINGS

[0002] The accompanying drawings illustrate various examples of the principles described herein and are part of the specification. The illustrated examples are given merely for illustration, and do not limit the scope of the claims.

[0003] Fig. 1 is a block diagram of a fluidic die with adjacent and orthogonal bond pad regions, according to an example of the principles described herein.

[0004] Fig. 2 is a top view of a fluidic die with adjacent and orthogonal bond pad regions, according to an example of the principles described herein. [0005] Fig. 3 is a block diagram of a print module with a fluidic die with adjacent and orthogonal bond pad regions, according to an example of the principles described herein. [0006] Fig. 4 is a top view of a print module with a fluidic die with adjacent and orthogonal bond pad regions, according to an example of the principles described herein.

[0007] Fig. 5 is a top view of a print module with a fluidic die with adjacent and orthogonal bond pad regions, according to another example of the principles described herein.

[0008] Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements. The figures are not necessarily to scale, and the size of some parts may be exaggerated to more clearly illustrate the example shown. Moreover, the drawings provide examples and/or implementations consistent with the description; however, the description is not limited to the examples and/or implementations provided in the drawings.

DETAILED DESCRIPTION

[0009] Fluidic die, as used herein, may describe a variety of types of integrated devices with which small volumes of fluid may be pumped, mixed, analyzed, ejected, etc. Such fluidic dies may include ejection dies, such as those found in printers, additive manufacturing distributor components, digital titration components, and/or other such devices with which volumes of fluid may be selectively and controllably ejected.

[0010] In general, print devices dispense fluid such as ink onto a surface in the form of images, text, or other patterns. The fluid may be held in a reservoir. The fluid in the reservoir is passed to a fluidic die that contains components that move or eject fluid. In a specific example, ejecting actuators may be coupled to nozzles. Through these nozzles, fluid, such as ink and fusing agent among others, is ejected.

[0011] These fluidic die are found in any number of print devices such as inkjet printers, multi-function printers (MFPs), page-wide printers, and additive manufacturing apparatuses. The fluidic die in these devices are used for precisely, and rapidly, dispensing and/or displacing small quantities of fluid. For example, in an additive manufacturing apparatus, the fluidic die dispenses fusing agent. The fusing agent is deposited on a build material, which fusing agent facilitates the hardening of build material to form a three-dimensional product.

[0012] Other fluidic die dispense ink on a two-dimensional print medium such as paper. For example, during inkjet printing, fluid is directed to a fluidic die. Depending on the content to be printed, the device in which the fluidic die is disposed determines the time and position at which the ink drops are to be released/ejected onto the print medium. In this way, the fluidic die releases multiple ink drops over a predefined area to produce a representation of the image content to be printed. Besides paper, other forms of print media may also be used.

[0013] Accordingly, as has been described, the systems and methods described herein may be implemented in a two-dimensional printing, i.e., depositing fluid on a substrate, and in three-dimensional printing, i.e., depositing a fusing agent or other functional agent on a material base to form a three- dimensional printed product. Such fluidic dies may be found in other devices such as digital titration devices and/or other such devices with which volumes of fluid may be selectively and controllably ejected.

[0014] As described above, such fluidic die may also be used in non ejecting applications. That is, fluid actuators may also be pumps. For example, some fluidic dies include microfluidic channels. A microfluidic channel is a channel of sufficiently small size (e.g., of nanometer sized scale, micrometer sized scale, millimeter sized scale, etc.) to facilitate conveyance of small volumes of fluid (e.g., picoliter scale, nanoliter scale, microliter scale, milliliter scale, etc.). Fluidic actuators may be disposed within these channels. Upon activation, these fluid actuators may generate fluid displacement in the microfluidic channel. Such fluid pumps may be used in non-ejecting applications or may be included on a printing device in an area where fluid is moved, but not ejected.

[0015] Each fluidic die includes a fluid actuator to eject/move fluid. In a fluidic ejection die, a fluid actuator may be disposed in an ejection chamber, which chamber has an opening. The fluid actuator in this case may be referred to as an ejector that, upon actuation, causes ejection of a fluid drop via the opening.

[0016] Examples of fluid actuators include a piezoelectric membrane- based actuator, a thermal resistor-based actuator, an electrostatic membrane actuator, a mechanical/impact driven membrane actuator, a magneto-strictive drive actuator, or other such elements that may cause displacement of fluid responsive to electrical actuation. A fluidic die may include a plurality of fluid actuators, which may be referred to as an array of fluid actuators.

[0017] While such fluidic die have undoubtedly advanced the field of precise fluid delivery, some conditions impact their effectiveness. For example, a print module used in a printing device may include a number of fluidic die and the print medium on which ink is to be deposited, may move underneath the fluidic die. As the print medium moves, the fluid actuators are activated to eject fluid onto the print medium. Each fluidic die has a “swath” which refers to a width of the fluidic die and a corresponding area on the print medium onto which the fluidic die can deposit fluid. Gaps between the swaths of individual fluidic die result in regions where print fluid is not deposited on the target surface. Accordingly, the present specification describes a print module with fluidic die in staggered rows such that there are no swath gaps across a width of the print medium.

[0018] Similarly, in some examples, a printing device such as a page wide print bar may include multiple print modules aligned end to end, each with multiple fluidic die. Gaps between fluidic die on adjacent print modules may lead to the same complication of areas on the print medium where fluid cannot be deposited. Accordingly, the present specification describes S-shaped print modules that may be tiled in an interlocking pattern such that fluidic die in one print module overlap with fluidic die in an adjacent print module such that no gap exists between fluidic actuators of adjacent print modules.

[0019] The use of such an S-shaped print module may lead to reduced space for a circuit board to which the fluidic die are connected. That is, to deliver energy to the fluid actuators that eject/move the fluid, a circuit board, referred to as an interposer circuit board, is used to transmit electrical signals from a printing device to the fluidic die. An S-shaped module introduces certain size characteristics for the interposer circuit board. Specifically, the area available for bonding between the fluidic die and the interposer circuit board is altered as bond pads are to be located adjacent to the interposer circuit board. For example, in rectangular-shaped print modules, each fluidic die may be surrounded on all sides by the interposer circuit board and bond pads may be evenly distributed across all four sides of the fluidic die or on the narrow ends of a fluidic die. However, due to the S-shape of the print module of the present specification, not all sides of every fluidic die are surrounded by this interposer circuit board.

[0020] Accordingly, the present specification describes a fluidic die that resolves these and other issues. Specifically, in order to use the same fluidic die (without geometric and dimensional variation) on the print module, fluidic die of the present specification have bond pads that are placed 1) on a single wide edge and 2) on a single adjacent and orthogonal narrow edge. The fluidic die are oriented differently to ensure that each fluidic die bond pad region is adjacent the interposer circuit board. That is, the present specification describes a fluidic die with two-sided adjacent interconnection between the bond pads of the fluidic die and the interposer circuit board.

[0021] Specifically, the print module of the present specification is an S- shaped print module that may be tiled with other print modules in an interlocking pattern. The print modules have an even number of identical fluidic die where bond pads are found on adjacent and orthogonal sides of each fluidic die. That is, since it is desirable that all fluidic die on the print module be identical, bond pads are placed on one end of the side die edge, and die on the top row are rotated 180 degrees relative to those on the bottom row.

[0022] In this example, a bondable region of each fluidic die, that is a region where bond pads are placed, is adjacent to the interposer printed circuit board. In some examples, actuator power bond pads are located near the center of a long edge of a rectangular fluidic die and data pads or other non actuator power bond pads are located on a short edge of the rectangular fluidic die. [0023] Specifically, the present specification describes a fluidic die. The fluidic die includes a substrate and fluid actuators disposed on the substrate.

The fluidic die also includes a first bond pad region disposed along a first edge of the substrate and a second bond pad region disposed along a second edge of the substrate. The second edge is adjacent and orthogonal to the first edge. [0024] The present specification also describes a print module. The print module includes a die carrier and an interposer circuit board disposed on top of the die carrier. A number of rows of fluidic die are disposed on the die carrier. Each fluidic die includes a right-angle bond pad area disposed at a same corner of each fluidic die. Fluidic die in the second row are rotated 180 degrees relative to fluidic die in a first row. Moreover, in this example, the interposer circuit board surrounds a subset of corners of any fluidic die.

[0025] The present specification also describes another example of a print module. In this example, the print module includes an S-shaped die carrier, a first circuit board to receive signals from a computing device, and an interposer circuit board disposed on top of a portion of the first circuit board to route signals from the first circuit board to fluidic die of the print module. The print module also includes a number of staggered rows of fluidic die disposed on the die carrier. In this example, the fluidic die are disposed around edges of the interposer circuit board such that a bond pad area of each fluidic die is adjacent the interposer circuit board and fluidic die in a second row are identical to fluidic die in a first row. Each fluidic die includes fluid actuators disposed on the substrate to displace a fluid, a first bond pad region disposed along a first edge of the substrate, and a second bond pad region disposed along a second edge of the substrate, which second edge is adjacent and orthogonal to the first edge. Also as described above, fluidic die in the second row are rotated 180 degrees relative to fluidic die in the first row.

[0026] In summary, such a fluidic die 1 ) provides fluidic actuator overlap regions, both on a single print module and between adjacent print modules; 2) enhances print zone geometries; 3) incorporates a single fluidic die for all die positions rather than unique fluidic die per position; 4) includes an overmolded support structure for enhanced mechanical robustness and serviceability; and 5) allows for uniform power distribution to each fluidic die on the print module. [0027] As used in the present specification and in the appended claims, the term “print device” is meant to be understood broadly as any device capable of selectively placing a fluid onto a print medium. In one example the print device is an inkjet printer such as a page-wide printer. In another example, the print device is a three-dimensional printer. In yet another example, the print device is a digital titration device.

[0028] Further, as used in the present specification and in the appended claims, the term “fluidic die” refers to a component of a fluid system that includes a number of fluid actuators.

[0029] Still further, as used in the present specification and in the appended claims, the term “print medium” is meant to be understood broadly as any surface onto which a fluid ejected from a nozzle of a fluidic die may be deposited. In one example, the print medium may be paper.

[0030] Accordingly, as used in the present specification and in the appended claims, the term “fluid actuator” refers to an individual component of a fluidic die that displaces fluid. The fluid actuator may be an ejecting fluid actuator, or ejector, or a non-ejecting actuator such as a fluid pump.

[0031] Turning now to the figures, Fig. 1 is a block diagram of a fluidic die (100) with adjacent and orthogonal bond pad regions (106, 108), according to an example of the principles described herein. As described above, a fluidic die (100) refers to a component that displaces small droplets of fluid. In use in a print device, the fluidic die (100) ejects small droplets of fluid in particular patterns onto a print medium, the ejection being controlled by a controller. The fluidic die (100) includes fluid actuators (104) that include components that effectuate the displacement of such fluid. As described above, a fluid actuator (104) may be ejecting fluid actuators (104) or non-ejecting fluid actuators (104). As a specific example, a controller on a print device sends signals to the fluidic die (100) to trigger sequential ejections by ejecting fluid actuators (104) such that fluid, such as ink, is deposited on the print medium in a particular pattern. [0032] The print medium may be any type of suitable sheet or roll material, such as paper, card stock, transparencies, polyester, plywood, foam board, fabric, canvas, and the like. In another example, the print medium may be a bed of powder material used in three-dimensional printing.

[0033] The fluidic die (100) includes a substrate (102). The substrate (102) forms a carrier that is attached to a print module such that fluid from a reservoir can be passed to, and expelled/moved by the fluid actuators (104).

[0034] These fluid actuators (104) may rely on various mechanisms to eject/move fluid. For example, an ejector may be a firing resistor. The firing resistor heats up in response to an applied voltage. As the firing resistor heats up, a portion of the fluid in an ejection chamber vaporizes to generate a bubble. This bubble pushes fluid out an opening of the fluid chamber and onto a print medium. As the vaporized fluid bubble collapses, fluid is drawn into the ejection chamber from a passage that connects the fluid chamber to a fluid feed slot in the fluidic die (100), and the process repeats. In this example, the fluidic die (100) may be a thermal inkjet (TIJ) fluidic die (100).

[0035] In another example, the fluid actuator may be a piezoelectric device. As a voltage is applied, the piezoelectric device changes shape which generates a pressure pulse in the fluid chamber that pushes the fluid through the chamber. In this example, the fluidic die (100) may be a piezoelectric inkjet (PIJ) fluidic die (100).

[0036] As described above, such fluid actuators (104) rely on energy to actuate. Accordingly, the fluidic die (100) includes an electrical interface to receive this energy. Accordingly, at appropriate times, the print device sends electrical signals to the fluidic die (100) via bond pads. The electrical signals pass through the bond pads and are routed through the substrate (102) to the fluid actuators (104). The fluid actuators (104) then displace a small droplet of fluid. As a specific example, an ejecting fluid actuator (104) ejects a small droplet of fluid onto the surface of the print medium. Such bond pads also facilitate the transmission of different kinds of data such as evaluation and monitoring data. [0037] Accordingly, the fluidic die (100) includes bond pad regions (106,

108) that provide the electrical connection between the printing system and the fluidic die (100) such that the fluid actuators (104) can be actuated and such that other components on the fluidic die (100) can also be powered and such that data may be transmitted between the fluidic die (100) and a computing device.

[0038] Specifically, a first bond pad region (106) is disposed along a first edge of the substrate (102) and a second bond pad region (108) is disposed along a second edge of the substrate (102). The second edge is adjacent and orthogonal to the first edge. That is, the first and second bond pad regions (106, 108) form a right-angle bond pad area where the bond pads may be located. As described above, placing the bond pads within these adjacent and orthogonal bond pad regions (106, 108) allows for a single fluidic die (100) configuration to be replicated across a print module, albeit at different orientations, such that bond pad regions (106, 108) of each fluidic die (100) are adjacent the interposer circuit board of a respective print module to facilitate electrical connections.

[0039] Fig. 2 is a top view of a fluidic die (100) with adjacent and orthogonal bond pad regions (106, 108), according to an example of the principles described herein. Fig. 2 clearly depicts the substrate (102) on which the fluid actuators (Fig. 1 , 104) are disposed. In this example, the fluid actuators (Fig. 1 , 104) are formed into arrays (210, 212) with each array (210, 212) being indicated as a solid rectangle. That is, fluid actuators (Fig. 1 , 104), such as ejecting fluid actuators (Fig. 1 , 104), may be arranged in columns or arrays such that properly sequenced ejection of fluid from the fluid actuators (Fig. 1 , 104) cause characters, symbols, and/or other graphics or images to be printed on the print medium as the fluidic die (100) and print medium are moved relative to each other. Note that for simplicity in Fig. 2, individual fluid actuators (Fig. 1 , 104) of the arrays (210, 212) are not depicted. In some examples, each array (210, 212) may pertain to a particular color. For example, a first array (210) may be fluidly connected to a reservoir of magenta ink and the second array (212) may be fluidly connected to a reservoir of cyan ink. [0040] Fig. 2 also clearly depicts the first and second bond pad regions (106, 108). As described above, the bond pad regions (106, 108) refer to areas on the substrate (102) where bond pads (214) are disposed. A bond pad (214) refers to an electrically-conductive material that is used to connect the fluidic die (100) to a trace through which an electrical signal is transmitted. That is, an electrical wire may be ball-bonded to the bond pad (214) to transmit data and/or power to/from the fluidic die (100). For simplicity in Fig. 2, just a few bond pads (214) having a particular form factor are represented and a single instance of a bond pad (214) is indicated with a reference number.

[0041] As described above, a first bond pad region (106) is disposed along a first edge, which may be a long edge of a rectangular substrate. This first bond pad region (106) may house actuator power bond pads (214). Such actuator power bond pads (214), as compared to other power bond pads, may convey a high voltage signal. For example, to eject fluid, each fluid actuator (Fig. 1 , 104) may receive a voltage of between 30 volts (V) and 35 V. Accordingly, these actuator power bond pads (214) may be sized to accommodate these high voltage signals.

[0042] In some particular examples, the actuator power bond pads (214) are disposed in the first bond pad region (106) at a central location of the first, and long, edge of the substrate (102). Doing so reduces difference in parasitic resistance along the paths from the bond pads (214) to the individual fluid actuators (Fig. 1 , 104) of the arrays (210, 212). That is, as the high voltage signals are transmitted from the bond pads (214) to the respective fluid actuators (Fig. 1 , 104), the voltage of that signal is modified due to the physical limitations of signal propagation. Accordingly, fluid actuators (Fig. 1 , 104) closer to the bond pads (214) may receive higher voltages as compared to fluid actuators (Fig. 1 , 104) that are farther away from the bond pads (214). Differences in received voltages can affect actuator operation, which can affect drop size. Accordingly, differences in voltages which result from different parasitic resistance can lead to disparity in ejected drop characteristics, which results in decreased print quality. By placing the actuator power bond pads (214) in the first bond pad region (106) at the center of the first edge, the different electrical paths between the bond pads (214) and respective fluid actuators (Fig. 1 , 104) is made more uniform, thus equalizing the parasitic resistance and increasing print quality.

[0043] Note that while it is mentioned that these higher voltage actuator power bond pads (214) are disposed on the first edge, other bond pads may be disposed in the first bond pad region (106) as well. For example, any of the below mentioned non-power and/or non-actuator power bond pads may be similarly positioned in this first bond pad region (106).

[0044] The second bond pad region (108) by comparison is along a second edge, which second edge is a short edge of the rectangular substrate (102).

This second bond pad region (108) may house other bond pads (220). For example, the fluidic die (100) may include any number of other components that are powered components, but for which the voltage may not be so great. For example, the fluidic die (100) may include components that provide power to lower voltage digital or analog circuits. Accordingly, these lower voltage bond pads (220) may be disposed along the second, and shorter, edge of the substrate (102) in the second bond pad region (108). For these components, there may be a reduced sensitivity to parasitic resistance.

[0045] In some examples, these other bond pads (220) may be non-power bond pads. Examples of non-power bond pads that may be found in this second bond pad region (108) include data bond pads that connect to data channels to convey fluid actuator (Fig. 1 , 104) data, clock bond pads, the aforementioned logic power supply bond pads, data bond pads for communicating with registers on the fluidic die (100) for operating in different modes, and configuration data bond pads, among others.

[0046] While the first and second edges have bond pad regions (106, 108) disposed thereon, a third edge and a fourth edge of the substrate (102) may be free of bond pad regions (106, 108) and bond pads (214, 220). That is, the bond pad regions (106, 108) may be disposed at a corner where two edges meet and the remaining sides and corners may be free of bond pad regions (106, 108). As will be shown in Fig. 4, placing the bond pad regions (106, 108) at a particular corner allows for this single fluidic die (100) to be re-instantiated across a print module and used with an interposer circuit board that has certain size characteristics based on being part of an S-shaped print module.

[0047] Fig. 3 is a block diagram of a print module (316) with a fluidic die (100) with adjacent and orthogonal bond pad regions (Fig. 1 , 106, 108), according to an example of the principles described herein. As described above, the print module (316) is a component that includes multiple fluidic die (100) and that is installed in a print device. Fluid is routed through the print module (316) to the fluidic die (100) where it is ultimately ejected.

[0048] The print module (316) includes a die carrier (318) that is a substrate on which the fluidic die (100) and other components for ejecting fluid are disposed. Disposed on the die carrier (318) is an interposer circuit board (322) to route the electrical signals from the print device to the fluidic die (100). This interposer circuit board (322) is electrically coupled to the fluidic die (100) such that the fluidic die (100), and more particular the bond pad regions (Fig. 1 , 106, 108) of the fluidic die (100), are to be adjacent this interposer circuit board (322). In one particular example, such an electrical coupling is via a wire-bond between the fluidic die (100) and the interposer circuit board (322).

[0049] Also disposed on the die carrier (318) are fluidic die (100). In one particular example, the fluidic die (100) are arranged in rows on the die carrier (318). As depicted in Fig. 4 below, the interposer circuit board (322) surrounds a subset of corners of any fluidic die (100). For example, in other systems the interposer circuit board (322) may surround all sides and corners of the fluidic die (100). However, with an S-shaped print module (316), the print module (316) of the current specification may include an interposer circuit board (322) that does not entirely surround each fluidic die (100) but partially surrounds each fluidic die (100) such that some corners of some fluidic die (100) are not completely surrounded by the interposer circuit board (322).

[0050] As described above, each fluidic die (100) includes multiple bond pad regions (Fig. 1 , 106, 108) that are on adjacent and orthogonal edges of the substrate (102). Put another way, each fluidic die (100) may include a right- angle bond pad area (324) disposed at a same corner of each fluidic die (100). For example, each fluidic die (100) may have corner indices that uniquely identify each corner of the fluidic die (100) relative to some point of origin. Accordingly, the right-angle bond pad area (324) which includes the bond pad regions (Fig. 1 , 106, 108) may be at a particular indexed corner. For example, each right-angle bond pad area (324) may be disposed at an upper right-hand corner, or put another way an upper right-hand corner of the fluidic die (100). However, as noted above, upon installation onto a print module (316), the orientation of the fluidic die (100) and thus the position of the right-angle bond pad area (324) may change relative to the print module (316). However, the position of the right-angle bond pad area (324) relative to other components of the fluidic die (100) may be the same for all fluidic die (100).

[0051] As described above, the fluidic die (100) may be arranged in rows.

In some examples, the fluidic die (100) in a second row may be rotated 180 degrees relative to fluidic die (100) in a first row. In so doing, the corner where the right-angle bond pad area (324) is located is different, relative to the die carrier (318) for fluidic die (100) in the first row as compared to fluidic die (100) in the second row. However, the position of the right-angle bond pad area (324) relative to other components of the fluidic die (100) may be the same for all fluidic die (100). Fig. 4 presents a pictographic example of such an arrangement.

[0052] Fig. 4 is a top view of a print module (316) with a fluidic die (100) with adjacent and orthogonal bond pad regions (106, 108), according to an example of the principles described herein. More particularly, Fig. 4 depicts multiple print modules (316-1 , 316-2, 316-3). As described above, the print modules (316) may be S-shaped such that they may tile in an interlocking pattern with other print modules (316-2, 316-3) such that fluid actuators (Fig. 1 ,104) of fluidic die (100) on one print module (316-1) overlap with fluid actuators (Fig. 1 , 104) of a fluidic die (100) of another print module (316-2, 316-3). Accordingly, as media travels perpendicular to the print modules (316), for example, from a bottom towards the top of the page in Fig. 4, there is no discontinuity in fluidic actuator (Fig. 1 , 104) pitch across the horizontal axis of a single print module (316), nor between fluidic die (100) on adjacent print modules (316). [0053] The print module (316) may include an S-shaped die carrier (318) that houses the various components of the print module (316). Fig. 4 also depicts a first circuit board (426) which may receive signals from a computing device and the interposer circuit board (322) that is disposed on top of a portion of the first circuit board (426). This interposer circuit board (322) routes signals from the first circuit board (426) to fluidic die (Fig. 1 , 100) of the print module (316). In other words, the electrical signal flow from a fluidic die (Fig. 1 , 100) to the print device is 1 ) from the bond pads (Fig. 2, 214) on a fluidic die (Fig. 1 , 100) to the interposer circuit board (322), 2) from the interposer circuit board (322) to the first circuit board (426), and 3) from the first circuit board (426) to flex connectors on the back side of the first circuit board (426) to the print device. While Fig. 4 depicts a first circuit board (426), in some examples, such as that depicted in Fig. 3, such a first circuit board (426) may be omitted. In this example, the interposer circuit board (322) may couple to flex connectors. [0054] As the fluidic die (Fig. 1 , 100) are to be coupled to the interposer circuit board (322), bond pads (Fig. 2, 214) on the fluidic die (Fig. 1 , 100) are to be adjacent to this interposer circuit board (322) to which they are electrically connected. Given the S-shape of the print module (316) routing to ends of each fluidic die (Fig. 1 , 100) may not be possible. Accordingly, to facilitate such interconnection of each fluidic die (Fig. 1 , 100) to the interposer circuit board (322), the fluidic die (Fig. 1 , 100) overlap edges of the interposer circuit board (322) such that the right-angle bond pad area (Fig. 3, 324) of each fluidic die (Fig. 1 , 100) is adjacent the interposer circuit board (322) and a second area of each fluidic die (Fig. 1 , 100) is not adjacent the interposer circuit board (322). More particularly, a fluidic die (Fig. 1 , 100) in each row may extend past the interposer circuit board (322) such that two sides of the fluidic die (Fig. 1 , 100) are not adjacent the interposer circuit board (322). In the example depicted in Fig. 4, the top-left fluidic die (Fig. 1 , 100) and the bottom-right fluidic die (Fig. 1 ,

100) are these afore described fluidic die (Fig. 1 , 100).

[0055] As the interposer circuit board (322) is directly connected electrically to the fluidic die (Fig. 1 , 100) and since the interposer circuit board (322) is in a particular area described, the bond pad regions (106, 108) for each fluidic die (Fig. 1 , 100) are adjacent the interposer circuit board (322). To avoid making each fluidic die (Fig. 1 , 100) unique, a single fluidic die (Fig. 1 , 100) configuration is replicated. That is, each fluidic die (Fig. 1 , 100) is identical to one another. Specifically, the dimensions of the right-angle bond area (Fig. 3, 324) of each fluidic die (Fig. 1 , 100) is the same. However, fluidic die (Fig. 1 , 100) in the second row are rotated 180 degrees relative to fluidic die (Fig. 1 ,

100) in the first row.

[0056] That is, in some examples, the fluidic die (Fig. 1 , 100) are arranged in staggered rows and arranged around edges of the interposer circuit board (322) such that a bond pad area (Fig. 3, 324) that includes the first and second bond pad regions (106, 108) is adjacent the interposer circuit board (322).

Given that each fluidic die (Fig. 1 , 100) in the second row is identical to fluidic die (Fig. 1 , 100) in the first row, but rotated 180 degrees, the bond pad region (106, 108) of each is adjacent the interposer circuit board (322). In some examples, each staggered row includes the same number of fluidic die (Fig. 1 , 100).

[0057] Fig. 4 clearly depicts the inverted nature of the fluidic die (Fig. 1 , 100) in the different rows. For example, in a first fluidic die (Fig. 1 , 100) which is in the first row, a right-angle bond pad area (Fig. 3, 324) is disposed in a lower right corner, a first array (210-1 ) is on an upper edge of the first fluidic die (Fig.

1 , 100), and a second array (212-1) is on a lower edge of the first fluidic die (Fig.

1 , 100).

[0058] By comparison, the right-angle bond pad area (Fig. 3, 324) of a second fluidic die (Fig. 1 , 100) in the second row is disposed at an upper left corner of the respective fluid die (Fig. 1 , 100), the first array (210-2) is on a lower edge of the second fluidic die (Fig.1 , 100) and the second array (212-2) is on an upper edge of the second fluidic die (Fig. 1 , 100). That is, the relative position of the elements on a single fluidic die (Fig. 1 , 100) are the same indicating the fluidic die (Fig. 1 , 100) are identical, but by being flipped and staggered, the relative position of respective bond pad regions (106, 108) to the interposer circuit board (322) has changed such that bond pad regions (106,

108) in each fluidic die (Fig. 1 , 100) are adjacent the interposer circuit board (322). Accordingly, rather than making fluidic die (Fig. 1 , 100) with different and unique component orientations, a single fluidic die (Fig. 1 , 100) can be implemented, albeit at different orientations, on the print module (316).

[0059] Such a fluidic die (Fig. 1 , 100) enhances performance in a print module (316) that incorporates an over-molded headland for enhanced mechanical robustness and serviceability and thus implements methods of interconnect to the fluidic die (Fig. 1 , 100) in an appropriate fashion.

Specifically, wire-bonds may be used to connect the interposer circuit board (322) to the fluidic die (Fig. 1 , 100) which wire-bond may be embedded in epoxy mold compound.

[0060] Accordingly, the print module (316) as described herein allows for interlocking tiled print modules (316) to ensure no gaps in coverage and accounts for electrical connections due to characteristics of an interlocking tiled design.

[0061] Fig. 5 is a top view of a print module (316) with a fluidic die (Fig. 1 , 100) with adjacent and orthogonal bond pad regions (106, 108), according to another example of the principles described herein. In the example depicted in Fig. 5, the fluidic die (Fig. 1 , 100) includes a strip (530-1 , 530-2) of interposer circuit board (322) surrounding at least one fluidic die (Fig. 1 , 100) such that the interposer material is adjacent three sides of each fluidic die (Fig. 1 , 100). In this example, bond pads (Fig. 2, 214) could be placed about the fluidic die (Fig.

1 , 100) to provide power on both ends of each fluidic die (Fig. 1 , 100). That is, such a configuration allows high voltage actuator bond pads (Fig. 2, 214) to be on each end of a particular fluidic die (Fig. 1 , 100) to improve uniformity of power parasitics from bond pads (Fig. 2, 214) to fluid actuators (Fig. 1 , 104). [0062] In some examples, each fluidic die (Fig. 1 , 100) may include probe pads (528) located outside of the first or second bond pad regions (106, 108). For simplicity, a single probe pad (528) is indicated with a reference number. Such probe pads (528) may be used in manufacturing, for example for quality assurance, but which are not bonded or connected during use. Accordingly, they may be removed from the interposer circuit board (322). [0063] In summary, such a fluidic die 1 ) provides fluidic actuator overlap regions, both on a single print module and between adjacent print modules; 2) enhances print zone geometries; 3) incorporates a single fluidic die for all die positions rather than unique fluidic die per position; 4) includes an overmolded support structure for enhanced mechanical robustness and serviceability; and 5) allows for uniform power distribution to each fluidic die on the print module.

Claims

CLAIMS What is claimed is:

1. A fluidic die, comprising: a substrate; fluid actuators disposed on the substrate; a first bond pad region disposed along a first edge of the substrate; and a second bond pad region disposed along a second edge of the substrate, which second edge is adjacent and orthogonal to the first edge.

2. The fluidic die of claim 1 , wherein a third edge and a fourth edge of the substrate are free of bond pads.

3. The fluidic die of claim 1 , wherein: the first bond pad region is disposed along a long edge of a rectangular substrate and houses actuator power bond pads; and the second bond pad region is disposed along a short edge of the rectangular substrate and houses other bond pads.

4. The fluidic die of claim 3, wherein the actuator power bond pads are disposed in the first bond pad region at a central location of the first edge.

5. The fluidic die of claim 1 , further comprising probe pads located outside of the first bond pad region and the second bond pad region.

6. A print module, comprising: a die carrier; an interposer circuit board disposed on top of the die carrier; a number of rows of fluidic die disposed on the die carrier, wherein: each fluidic die comprises a right-angle bond pad area disposed at a same corner of each fluidic die; fluidic die in a second row are rotated 180 degrees relative to fluidic die in a first row; and the interposer circuit board surrounds a subset of corners of any fluidic die.

7. The print module of claim 6, wherein the fluidic die are identical to one another.

8. The print module of claim 6, wherein the fluidic die overlap edges of the interposer circuit board, such that the right-angle bond pad area of each fluidic die is adjacent the interposer circuit board.

9. The print module of claim 8, wherein a second area of each fluidic die is not adjacent the interposer circuit board.

10. The print module of claim 6, wherein a fluidic die in each row extends past the interposer circuit board such that two sides of the fluidic die are not adjacent the interposer circuit board.

11. The print module of claim 10, further comprising a strip of interposer circuit board surrounding the fluidic die such that the interposer circuit board is adjacent three sides of each fluidic die.

12. The print module of claim 6, wherein each row comprises a same number of fluidic die.

13. The print module of claim 6, wherein dimensions of the right-angle bond pad area of each fluidic die is the same.

14. A print module, comprising: an S-shaped die carrier; a first circuit board to receive signals from a computing device; an interposer circuit board disposed on top of a portion of the first circuit board to route signals from the first circuit board to fluidic die of the print module; and a number of staggered rows of fluidic die disposed on the die carrier, wherein: the fluidic die are disposed around edges of the interposer circuit board such that a bond pad area of each fluidic die is adjacent the interposer circuit board; fluidic die in a second row are identical to fluidic die in a first row; each fluidic die comprises: a substrate; fluid actuators disposed on the substrate to displace fluid; a first bond pad region disposed along a first edge of the substrate; and a second bond pad region disposed along a second edge of the substrate, which second edge is adjacent and orthogonal to the first edge; and fluidic die in the second row are rotated 180 degrees relative to fluidic die in the first row.

15. The print module of claim 14, wherein the print module is tiled in an interlocking pattern with other print modules such that fluid actuators of fluidic die on one print module overlap with fluid actuators on a fluidic die of another print module.