Patent Publication Number: US-10780698-B2

Title: Inverted TIJ

Description:
BACKGROUND 
     Fluid ejection dies such as printhead dies are composed of a substrate and thin film layers. The thin film layers are disposed on the substrate and may include at least one chamber layer and a nozzle plate with nozzles. Actuators such as heat resistors are provided in ejection chambers of the chamber layer to eject the fluid out of the chambers through the nozzles. The substrate is doped and thin film circuitry is patterned throughout the thin film layers. 
     A flexible electrical circuit may extend around or next to the die to connect to bond pads of the die. The flexible electrical circuit may route electrical connections to a further printer circuit such as a controller. In a typical printhead, part of the electrical connections between the flexible circuit and die are provided on the head side of the die, for example using bond pads near an edge of the substrate. 
     Fluid supply slots run through the substrate. The fluid supply slots supply fluid to the channels and chambers in the thin film layers. The channels may include a manifold to fluidically connect a fluid supply slot to individual ejection chambers. During fluid ejection, fluid runs through the slots, the manifold channel, and into the ejection chambers. The heat resistors heat the fluid in the chambers, thereby forming vapor bubbles that push the fluid out of the nozzles. The nozzle plate may have a protective coating to prevent mechanical or chemical damage, e.g., from ink, crusted ink, servicing, wiping, etc. 
    
    
     
       DRAWINGS 
         FIG. 1  illustrates a diagram of an example of a fluid ejection die. 
         FIG. 2  illustrates a diagram of an example of a fluid ejection device. 
         FIG. 3  illustrates a perspective view on a portion of an example of a fluid ejection die. 
         FIG. 4  illustrates a different, partially cross sectional, perspective view on a portion of the example fluid ejection die of  FIG. 3 . 
         FIG. 5  illustrates a partially cross sectional top view on a portion of the example fluid ejection die of  FIGS. 3 and 4 . 
         FIG. 6  illustrates a side view of a fluid path and resistor of the example fluid ejection die of  FIGS. 3-5 . 
         FIGS. 7-10  illustrate diagrams of different example configurations of drop generators including resistors and nozzles. 
         FIG. 11  illustrates a method of manufacturing a fluid ejection die. 
         FIG. 12  illustrates an example of wafer and thin film layers for manufacturing a fluid ejection die. 
         FIG. 13  illustrates the example wafer and thin film layers of  FIG. 12  in a later manufacturing stage. 
         FIG. 14  illustrates a diagram of an example of a fluid ejection die in a packaging. 
     
    
    
     DESCRIPTION 
       FIG. 1  illustrates a diagram of an example of a fluid ejection die  1 . In one example, the fluid ejection die is a MEMS (Micro-Electromechanical System). The die  1  includes a substrate  3  and at least one thin film layer  5 . The at least one thin film layer  5  is disposed on the substrate  3 . The at least one thin film layer  5  may be a thin film layer stack including thin film circuitry and fluid channels, thereby forming a MEMS. In an example, the substrate  3  includes silicon and the at least one thin film layer  5  includes SU8, dielectric, polymide, metal, or other polymer materials. 
     The substrate  3  includes a nozzle array of ink ejection nozzles  7 . The thin film layer  5  includes fluid channels including ejection chambers  9 . The ejection chambers  9  are fluidically connected to the nozzles  7 . The thin film layer  5  includes fluid ejection circuitry. The fluid ejection circuitry includes thin film fluid ejection actuators  11  to eject the fluid from out through the nozzles  7 . The actuators  11  are disposed upstream of the nozzles  7 , in the chambers  9 . At least one actuator  11  is disposed in each chamber  9 . At least one actuator  11  is associated with each nozzle  7 . The fluid ejection circuitry may further include electrical drive circuitry, such as fire wires, connected to the actuators  11 . As indicated by fluid flow direction  13  and fluid drop  15 , fluid is ejected from the fluid chambers  9  and/or channels in the at least one thin film layer  5 , through the nozzles  7  in the substrate  3 . 
     Different effects can be associated with such a fluid ejection die  1  wherein the substrate  3  is provided downstream of the at least one thin film layer  5 . In one example, electrical bond pads or contacts of the die  1  can be provided at an upstream side  17  of the substrate  3 , opposite to a head surface  19 . Thereby electrical contacts or electrical circuitry protruding from the head surface  19  can be inhibited. Also, since the substrate  3  can form the nozzle plate instead of thin film layers, such novel nozzle plate can facilitate a relatively flat fluid ejection die head surface  19  as compared to head surfaces formed by thin film layer stacks. Hence, the head surface  19  can be relatively flat due to one or both of (i) an absence of electrical interconnect components protruding from the head surface and (ii) a silicon substrate that may act as nozzle plate surface. 
     One other example effect is that the substrate  3  functions as a shield, for example for the thin film circuitry behind it, for example with few or no additional layers needed on the head surface to protect it, although protective coating may be provided for different reasons. In an example wherein the substrate  3  is mostly composed of silicon, the substrate  3  can be relatively robust against potential negative chemical influences of the ejected fluids, e.g., ink, without needing an additional coating. Also the substrate  3  can provide for a nozzle plate that is relatively robust against heat, which may facilitate functioning in a relatively hot environment. In one example substrate nozzle plates may be more robust against heat than SU8 thin film nozzle plates. In another example, a head surface formed by the silicon substrate  3  may inherently be robust against mechanical handling, such as servicing procedures such as wiping, or may be more robust against nozzle tape removal. Other substrate materials, such as glass, may have similar effects. 
     In one example, the substrate  3  may be a relatively thin substrate  3 , and/or a substrate  3 . In a further example, the substrate  3  can be of a reduced thickness as compared to an original thickness of an original wafer that was used to produce the substrate from. In one example a thinner substrate  3  may facilitate an appropriate depth of the nozzles to facilitate appropriate nozzle functioning. As a consequence the die  1  may also be relatively thin. For example the total thickness t of the die  1  can be approximately 500 micron or less, approximately 300 micron or less, approximately 200 micron or less, or approximately 150 micron or less. In one example such a relatively thin die  1  is referred to as a thin sliver die. For example the die may be relatively flexible and may need a packaging for support and/or reinforcement. 
     A thickness t 2  of the substrate  3  may be more than a total thickness t 1  of the thin film layers  5 , wherein the sum of these thicknesses t 1 , t 2  forms the total thickness t of the die  1 . In one example a depth D of each nozzle  7 , formed through the substrate  3 , between the upstream side  17  and the head surface  19 , is more than a total thickness t 1  of the thin film layer stack  5  of the die  1 . 
       FIG. 2  illustrates a diagram of an example of a fluid ejection device  121  including a fluid ejection die  101 . The fluid ejection die  101  may include all features discussed with reference to the example die of  FIG. 1 . In the example of  FIG. 2 , the die  101  is supported by, or embedded in, a carrying structure such as packaging  123 . The packaging  123  embeds or supports further electronic components  125 , such as drive circuitry for the die  101 . The die  101  includes a contact  127  on an upstream side  117  of its substrate  103 . This contact  127  is wired to the further electrical components  125 , from the upstream substrate side  117  to the component  125 , whereby the electrical interconnection, e.g., wiring  131 , is inhibited from protruding from a head surface  119  of the device  121 . All electrical interconnections can be fully shielded by the substrate  103  and/or packaging  123 . For example the electrical interconnect wiring  131  can be embedded in the packaging  123 . The contact  127  may be disposed directly on the upstream side  117  of the substrate  103 , for example next to the thin film layers  105 , for example near an edge  129  of the substrate  103 . In another example the contact  127  can be disposed on the thin film layers  105 , for example near the edge of the thin film layers  105  and/or substrate  103 . 
     The packaging  123  may further comprise a fluid supply slot  133  to supply fluid to fluid channels and/or chambers  109  of the thin film layers  105 . Actuators  111  in the chambers  109  are to eject the supplied fluid through nozzles  107  in the substrate  103 . The thin film layers  105  extend between the packaging  123  and the substrate  103 , and/or between the fluid supply slot  133  and the substrate  103 , so that in use fluid flows from the packaging  123  to the thin film layers  105 , engaging first packaging walls  123  and subsequently thin film layer walls such as chamber or channel walls. The fluid flows from the thin film layers  105 , out of the ejection chambers  109 , through the substrate  103 , as indicated with fluid flow direction arrow  113 . Nozzles  107  are provided through the substrate  103 , fluidically connected to the chambers  109 , to eject the fluid out through the nozzles  107  by actuation of the actuators  111 . Actuation of the actuators  111  may be driven by drive circuitry of the electric component  125  and/or in the thin film layers  105 . 
     Where the die  101  is placed in or on the packaging  123 , adhesive can be provided between the die  101  and packaging  123 , around the at least one fluid supply slot  133 . The adhesive may adhere to the thin film layers  105  on one side, and to the packaging  123  one the other side. The electrical interconnect wiring  131  can at least partly extend through the adhesive and/or encapsulate. In another example the die  101  can be directly overmolded in the packaging  123 . The electrical interconnect wiring  131  and/or electrical component  125  can be directly overmolded in the packaging  123  together with the die  101 . Instead of a packaging  123  any other suitable carrying structure can be used. 
       FIGS. 3-5  illustrate a portion of an example fluid ejection die  201 . The example die  201  is illustrated with an example packaging  223  in  FIGS. 4 and 5 .  FIG. 6  illustrates a corresponding fluid flow path. The fluid ejection die  201  may be for ejecting a single fluid type, for example a single color ink, wherein the illustrated two nozzle columns may be to eject the same fluid as provided by the same fluid slot  233 . 
     The die  201  includes a substrate  203  and fluidic thin film layers  205 A,  205 B on the substrate  203 . The substrate  203  includes nozzles  207  through the entire thickness of the substrate  203 . A thin film chamber layer  205 A may be provided onto the substrate  203 . The thin film chamber layer  205  includes an array of chambers  209 , for example two columns of chambers  209 . The chambers  209  are fluidically connected to the nozzles  207 . Actuators  211  such as heat resistors may be disposed in the chamber layer  205 , in each of the chambers  209 . A fluid supply layer  205 B extends upstream of the chamber layer  205 A. Fluid supply channels such as manifold channels  235  extend through the fluid supply layer  205 B and the chamber layer  205 A, to fluidically connect an external fluid supply slot  233  to each of the chambers  209 . The illustrated opposite manifold channels  235  connect to the same fluid supply slot  233 . In other examples, instead of a single manifold channel  235  connecting to a full column of chambers  209 , single discrete fluid supply holes may be provided in the fluid supply layer  205 B to connect the external fluid supply slot  233  to the individual chambers  209 . In yet other examples multiple discrete manifold channels connect to smaller groups of chambers within the full column of chambers. 
     Inlets  237  are provided between the manifold channel  235  and each chamber  209  of a corresponding column of chambers  209 . In this example, the inlets  237  extend laterally to a length of the manifold channel  235  and laterally to a length of the column of chambers  209 . The manifold channels  235  connected to the chamber columns extend along the outer sides of the chamber columns, so that both chamber columns extend between the manifold channels  235 . Also the nozzles columns associated with respective chamber columns extend at the inner sides of the manifold channels  235 , as seen from a top view ( FIG. 5 ). Hence, within the die  201 , the fluid is supplied to each nozzle column  207 A from separate fluid channels  235  that extend at laterally outer sides of the nozzle columns. 
     The actuator  211  may extend between the inlet  237  and the nozzle  207 . In an example fluid ejection scenario, fluid may flow downwards from the fluid slot  233  into the manifold channels  235 . The fluid flow may split into multiple flows to enter multiple parallel manifold channels  235 , two of which are shown in the die of  FIGS. 3-5 . Referring to  FIG. 6 , the fluid may flow downwards through each manifold channel  235 , as illustrated by fluid flow direction FF. At a bottom of each manifold channel  235  the fluid changes course, flowing laterally into individual chambers  209 , over respective actuators  211 . Each actuator  211  may pressurize the fluid in the chamber  209 , for example by heat or vibration, whereby the fluid is pushed out of the chamber  209 , again changing course, this time in a downwards direction through the nozzle opening  207  in the substrate  203 , from where it is ejected out of the die  201 . As illustrated in  FIG. 6 , opposite nozzles  207  of opposite nozzle columns may extend closer to each other than opposite chambers  209  of opposite chamber columns and opposite fluid supply inlets  237 . The manifold channels  235  may extend at lateral outer sides of the illustrated opposite fluidic paths. The two separate fluidic paths diverge to each other, through the inlets  237  and chambers  209 , to the opposite nozzle columns. In other example certain fluid supply channels other than longitudinal manifold channels may be provided, such as for example columns of discrete fluid supply holes, each fluid supply hole connected to a chamber and the chamber column and fluid supply hole column extending parallel to each other, wherein the fluid supply hole columns may similarly extend laterally and externally along the chamber columns. 
     In the illustrated example, the actuators  211  extends between the inlet  237  of the chamber  209  and the nozzle  207 . The nozzle  207  opens into a wall  243  of the chamber  209 , forming a nozzle inlet  207 A in said wall  243 . The actuator  211  is disposed on the substrate  203 , next to and on the same chamber wall  243  as the nozzle inlet  207 A. In the illustrated example, wherein the die  201  may be configured for downwards fluid ejection, the actuator  211  and nozzle inlet  207 A are provided on and in, respectively, the floor of the ejection chamber  209 . For example electrode traces or further thin film layer portions may extend between the actuator  211  and the substrate  203 . At least one other thin film layer, such as a passivation layer may extend over the resistor  211 . 
     In the illustrated example, the fluid inlets  237  of the chambers  209 , between the manifold channels  235  and the chambers  209 , include projections  237 A that extend into fluid channel between the manifold channel  235  and the chamber  209 . The projections define, and narrow, an inlet width Wi. The width Wi of the inlet  237 , between the projections  237 A, may be less than an average chamber width We of the chamber  209 , wherein the width We of the chamber  209  is defined as parallel to the width Wi. 
     As explained above, instead of a single manifold channel  235 , other fluid supply channel arrangements can be used to supply fluid from a fluid supply slot  233  external to the die  201  to the individual chambers  209 . As illustrated in  FIG. 5A , multiple in-line manifold channels  235 A parallel to the chamber column may extend in line with each other, along one axis L, wherein each of the in-line manifold channels  235 A fluidically connects to a sub-column of chambers  209 A and wherein each sub-column  241  is part of the same larger column of chambers  209 A. Hence each sub-column  241  is fluidically disconnected within the die  201 . Each sub-column  241  may contain at least two chambers  209 A. In again a different example, individual fluid supply holes are formed through the thin film layers  205  to guide fluid from an external fluid supply slot to each of the individual chambers whereby the fluid supply holes may be fluidically disconnected within the die  201 . 
       FIGS. 7-10  illustrate diagrams of different examples of top views of drop generators  345 ,  445 ,  545 ,  645 , each drop generator  345 ,  445 ,  545 ,  645  including an ejection chamber  309 ,  409 ,  509 ,  609 , nozzle  307 ,  407 ,  507 ,  607 , chamber inlet  337 ,  437 ,  537 ,  637 , inlet projections  337 A,  437 A,  537 A,  637 A and at least one actuator  311 ,  411 ,  511 ,  611 . In an example the actuator  311 ,  411 ,  511 ,  611  is disposed on the same wall as an inlet of the nozzle  307 ,  407 ,  507 ,  607 . In an example the actuator  311 ,  411 ,  511 ,  611  is a thermal resistor to heat fluid to eject the fluid. The nozzle  307 ,  407 ,  507 ,  607  runs through the substrate as described in other examples of this disclosure. A fluid supply channel  335 ,  435 ,  535 ,  635  is to provide fluid to each chamber  309 ,  409 ,  509 ,  609  through the respective inlet  337 ,  437 ,  537 ,  637 . At least one thin film layer  305 ,  405 ,  505 ,  605  extends around the chambers  309 ,  409 ,  509 ,  609  and inlets/channels  337 ,  437 ,  537 ,  637 ,  335 ,  435 ,  535 ,  635 . The top view may be onto an upstream side of a substrate, onto which the at least one thin film layer  305 ,  405 ,  505 ,  605  and actuator  311 ,  411 ,  511 ,  611  are disposed. Instead of, or in addition to, the inlet projections  337 A,  437 A,  537 A,  637 A at least one of baffles, bubble tolerant architectures and particle tolerant architectures may be formed in or near the inlet  337 ,  437 ,  537 ,  637 . 
       FIG. 7  illustrates an example of a drop generator  345  wherein the actuator  311  is disposed around the nozzle  307 , substantially donut-shaped, covering almost a full circle wherein opposite ends  311 A are disconnected. These ends  311 A may extend close to each other. Electrodes may contact each end of the actuator  311  for actuation. In different examples the actuator  311  may cover at least 270 degrees around the nozzle  307 , or at least 345 degrees, and less than approximately 358 degrees, or less than approximately 350 degrees. In another example the actuator  311  could be circular shaped and cover a full circle whereby opposite electrodes may contact the inner and outer edges of the actuator  311 , or opposite outer edges of the actuator  311  on opposite sides of the nozzle  307 . 
       FIG. 8  illustrates an example of a drop generator  445  wherein the nozzle  407  is non-circular shaped. For example the nozzle  407  is symmetrical along a longitudinal axis L. The nozzle  407  may have a substantially longitudinal shape along said axis L, and/or an elliptical shape whereby a length direction of the ellipse extends along the longitudinal axis L. The actuator  411  may extend around the nozzle  407  wherein the inner and outer edge of the actuator  411  may be offset from the circumference of the inlet of the nozzle  407 . In different examples the actuator  411  may extend fully or partially around the nozzle  407 . For example the actuator  411  may be interrupted so as to be defined by four separate actuators  411 . 
       FIG. 9  illustrates an example wherein the actuator  511  extends next to the nozzle  507  on an opposite side of the nozzle  507  with respect to the chamber inlet  537 . In another example, two resistors could be disposed along opposite sides of the nozzle  507 , for example one resistor as shown in  FIG. 9  and another resistor between the nozzle  507  and the inlet  537 , as shown in  FIG. 5 . In yet another example a single resistor may extend along one side of the nozzle  507 , between the nozzle  507  and the inlet  537 , as shown in  FIG. 5 .  FIG. 10  illustrates an example wherein the actuator  611  extends on opposite sides of the nozzle  607 . The actuators  611  may extend laterally to the nozzle  607  with respect to a fluid in-flow direction Fi in the inlet  637 . In other examples more than two separate actuators may extend around the nozzle, at different sides of the nozzle. In again other examples, different shapes, numbers and locations of actuators can be chosen to extend next to, and/or at least partially around, a single nozzle, and on the same wall as the nozzle inlet. 
       FIG. 11  illustrates a flow chart of an example method of manufacturing a fluid ejection die  701  of this disclosure.  FIGS. 12 and 13  illustrate examples of intermediate products of such method. The method of  FIG. 10  includes forming hole arrays  753  in a wafer  751  through part of a thickness T of the wafer  751  (block  100 ). In one example the wafer  751  includes silicon. In one example the hole array is formed by using a photoresist to define nozzle patterns in the wafer, and then dry etch, for example by deep reactive-ion etching. 
     The method further includes disposing at least one thin film layer  705  onto the wafer  751  (block  110 ). The method further includes patterning arrays of fluidic actuators and fluidic chambers  709 /channels in the at least one thin film layer  705 , so that the chambers  709 /channels fluidically connect to the hole array  753  (block  120 ). Forming the fluidic chambers  709  and channels may be achieved by patterning and etching, for example after filling the hole array  753  with a protective sacrificial material, e.g. wax or other material, after which filling at least one thin film may be laminated over and/or between the protective material. 
     Separate thin film devices  705 A, each formed of said thin film layers  705 , may spread like a grid over the wafer  751 , to connect to corresponding separate hole arrays  753 , and to form part of respective fluid ejection dies  701 .  FIG. 12  illustrates a diagrammatic example of an intermediate product in this stage of the manufacturing method. In a further example, electrical circuitry is patterned in/on the thin film layers  705  wherein the electrical circuitry may include electrical bond pads  727  that extend next to the thin film layers  705 , for example near dicing lines  755  of the wafer  751 , to later connect to further electrical components outside of the die  701 . 
     The method further includes reducing a Thickness T of the wafer  751  at the opposite side  719  (downstream side), i.e. opposite with respect to the at least one thin film layer  705 . In the method, the thickness T may be reduced until the holes are completely exposed at said opposite side  719  so that the holes extend completely through the wafer  751  to form ejection nozzles  707  (block  130 ). In one example the wafer  751  is ground to its end thickness. In a further example, the downstream wafer side  719  is finished with dry polishing after it has been reduced in thickness. In one example the thickness of the substrate  703  and correspondingly the depth of the nozzles  707  is between approximately than 10 and approximately 100 micron, for example between 12 and 80 micron, for example between 15 and 60 micron or for example between approximately 20 and approximately 40 micron. In certain examples the nozzles have counter bores around their outlets, i.e., a stepped outlet, for example to reduce an effective depth of the nozzle with respect to T thickness T of the thinned substrate. 
     In an example, at least one thin film layer  705  extends over the nozzle  707 , e.g., forming a roof of an ejection chamber  709  over the nozzle  707 . The method further includes dicing the wafer  751  over said dice lines  755  to form a plurality of fluid ejection dies  701  (block  140 ). In one example the wafer  751  is diced between the thin film fluidic devices  705 A, for example near electrical contact pads  727  that will after dicing extend near an edge of each fluid ejection die  701 .  FIG. 13  illustrates a diagrammatic example of an intermediate product after such dicing. 
     Some of the examples of this disclosures are thin sliver dies, having a substrate of reduced thickness t 2 , T (e.g.  FIG. 1, 13 ) and a relative thin thin film layer stack. The combined thickness t (e.g.  FIG. 1, 13 ) of the substrate t 2 , T and the thin film layers t 1  can be less than approximately 300 micron, less than approximately 200 micron or less than approximately 100 micron. As illustrated by  FIG. 14  a thin sliver die  801  of this disclosure that has a substrate  803  as nozzle plate may have a relatively narrow width Ws, for example less than 5 millimeters, less than 3 millimeters, less than 1.5 millimeters, less than 1 millimeter or less than 0.5 millimeters. A ratio length Ls:width Ws of the die  801  can be relatively high, for example at least approximately 50:1. The length Ls and width Ws may be measured between outer edges of the die substrate  803 . At least one nozzle columns  807 B may extend parallel to the length direction. The illustrated example die  801  includes two nozzle columns  807 B through the substrate  807 B. The thin die  801  may be reinforced by the packaging  823 , for example by embedding or overmolding the die  801  in packaging compound. 
     A fluidic MEMS of this disclosure may have any combination of the described features and effects. In one aspect a MEMS can include a die. The die may include (i) a substrate including an array of nozzles extending through the substrate and (ii) thin film layers on the substrate, including fluid ejection actuators associated with the nozzles. The thin film layers may include ejection chambers associated with the nozzles. The thin film layers may further include an array of fluid inlets to supply fluid to these chambers. 
     The substrate may form or support a wall of the ejection chamber, wherein a nozzle inlet opening is formed in the wall. Each actuator may be disposed on the same wall as the nozzle inlet opening, for example next to the nozzle inlet opening. In one example the actuator is a heat resistor to form a vapor bubble in fluid. In other examples the actuator may be any other type of fluid dispensing actuator such as a piezo actuator. For example at least a portion of the actuator is disposed between the chamber inlet and the nozzle inlet. In a further example the actuator is disposed at least partially around or at multiple sides of the nozzle inlet opening. 
     In a further example, the substrate includes two parallel nozzle columns, wherein separate columns of ejection chambers and fluid supply inlets are associated with each nozzle column, and wherein these columns are fluidically disconnected from each other in the die. In one example, fluid supply inlets to each ejection chamber extend at lateral outer sides of the ejection chamber column. For example fluid supply holes may extend at lateral outer sides of the inlet column, through the thin film layers, to supply fluid to the chambers through each inlet. 
     In one example the thin film layers include ( ) electrical circuitry, and (ii) electrical contacts connected to the electrical circuitry, for connection to drive circuitry external to the die. The electrical contacts can be disposed at the thin film layer side of the substrate, for example near at least one edge of the substrate to readily connect the electrical circuitry to said external drive circuitry. In a further example a packaging is provided to package the die. The packaging may including at least one fluid supply slot to supply fluid to the fluid supply inlets. For example fluid supply holes may fluidically connect the slot to the inlets. Thin film layers extend between at least one of (i) the packaging and the substrate, and (ii) the fluid supply slot and the substrate. In a further example the external drive circuitry is provided in or on the packaging. 
     In a further example, the die includes (i) a pair of parallel nozzle columns to eject fluid, (ii) at least one first fluid supply hole to let fluid into the die to supply fluid to at least one ejection chamber associated with a first of the pair of nozzle columns, and (iii) at least one second supply hole to let fluid into the die to supply fluid to ejection chambers associated with a second of the pair of nozzle columns. The first and second fluid supply holes are fluidically connected to the same at least one fluid supply slot. In one example a lateral distance between said nozzle columns is smaller than a lateral distance between said first and second fluid supply holes. The first fluid supply hole associated with a first nozzle column can be either (i) a column of discrete supply holes connected to single chamber inlets or sub-groups of chamber inlets, or (ii) an single elongate fluid supply hole connected to a column of chamber inlets. The manifold channel  235  illustrated in the example of  FIGS. 3-5  is an example of an elongate fluid supply hole in the thin film layers. In different examples, a fluid supply slot of the packaging can supply fluid to the at least one fluid supply hole in the thin film layers. 
     In one example a depth of the nozzles is more than a thickness of the thin film layers, and the sum of that depth and thickness approximately equals the total thickness of the die. In a further example the thickness of the die is less than approximately 300 micron. 
     In a further aspect this disclosure provides for a method of manufacturing fluid ejection dies. Such method may include (i) forming hole arrays in a wafer through part of its thickness, (ii) disposing at least one thin film layer over the wafer, (Iii) patterning arrays of fluidic actuators and fluid chambers/channels in said at least one thin film layer to fluidically connect to the hole arrays, (iv) reducing a thickness of the wafer at opposite side with respect to the at least one thin film layer until holes extend completely through the wafer to form ejection nozzles, and (v) dicing the wafer to form a plurality of fluid ejection dies.