CN1796127A - Fluid ejection device with sensor and method of making same - Google Patents

Abstract

The invention provides a fluid ejection device with a sensor and a method of manufacturing the same. The fluid ejection device includes a substrate. A structural layer is disposed on the substrate and forms a fluid chamber with the substrate. At least one bubble generating device is arranged on the structural layer at the corresponding side of the fluid cavity. At least one linear resistance sensor connected to the fluid chamber. A protection layer covering the bubble generating device and the linear resistance sensor. And a nozzle, which is adjacent to the bubble generator, penetrates the protective layer and the structural layer, and is communicated with the fluid cavity.

Description

Fluid ejection device with sensor and method of making same

technical field

The present invention relates to a fluid ejection device and a manufacturing method thereof, in particular to a fluid ejection device with a sensor and a manufacturing method thereof, through which the formation of a fluid cavity can be monitored in real time during the manufacturing process.

Background technique

Microfluid ejection devices have recently been widely used in the information industry, such as in inkjet printers or the like. With the gradual development of micro system engineering, this kind of fluid injection device is gradually applied to many other fields, such as fuel injection system, cell sorting, drug delivery system , printing lithography (print lithography) and micro jet propulsion system (micro jet propulsion system), etc. Among the aforementioned application fields, a relatively successful design uses thermally driven bubbles to eject micro-droplets. It is also the most commonly used due to its simple design and low cost.

Fig. 1 shows a monolithic fluid ejection device 1 of U.S. Patent No. 6,102,530 in the prior art, which uses a silicon substrate 10 as a body, and forms a structural layer 12 on the silicon substrate 10, and on the silicon substrate 10 A fluid cavity 14 is formed between the structural layer 12 to accommodate the fluid 26; and a first heater 20 and a second heater 22 are arranged on the structural layer 12, and the first heater 20 is used for the fluid cavity 14 A first air bubble 30 is generated in the fluid chamber 14 , and the second heater 22 is used to generate a second air bubble 32 in the fluid chamber 14 to eject the fluid 26 in the fluid chamber 14 .

Since the monolithic fluid injection device 1 has a virtual valve design, and has the characteristics of high arrangement density, low interaction interference, and low heat loss, and does not need to be assembled to join the orifice sheet, it can reduce production. cost.

However, in the prior art monolithic fluid ejection device 1, the structural layer 12 is mainly composed of low stress silicon nitride. During manufacture, its thickness has a direct effect on the life of the fluid ejection device. In addition, for the designers of the fluid ejection device, the fluid ejection effect and service life of the fluid ejection device are the focus of attention. Therefore, whether the etching process during the formation of the fluid cavity can be accurately controlled will critically affect the accuracy of the size of the fluid cavity, and also have a great influence on the performance of the fluid ejection properties.

In addition, for thermal bubble-driven fluid injection devices, if the fluid in the fluid chamber is not filled enough, in addition to affecting the uniformity of the ejected microfluidic droplet size, it may also cause the "empty firing effect" of the heater to cause heating. premature damage to the device.

Traditionally, for the control of the etching process, the prior art mostly utilizes a control wafer to monitor the etching result as a comparison benchmark of the etching progress. In this method, various parameters in the etching process, such as: etchant concentration, temperature, etc., must be under precise control before effective comparison can be made. In addition to the complicated procedures required, it also requires additional costs (such as the cost of film control), and the results cannot be measured in real time. On the other hand, the detection method of fluid filling is mostly based on the change of the resistance value of the heater in the fluid ejection device, but this method will directly affect the heater during the detection process, so the accuracy is also questioned.

Contents of the invention

Therefore, it is an object of the present invention to provide a fluid ejection device with a sensor. Through the sensor element, the formation of the fluid cavity can be monitored in real time during the manufacturing process, and the size of the fluid cavity can be precisely controlled.

Another object of the present invention is to provide a fluid ejection device with a sensor. Through the sensor element, the filling height of the liquid in the nozzle hole can be monitored in real time, so as to improve the accuracy of ejecting liquid droplets.

Another object of the present invention is to provide a method for manufacturing a fluid ejection device. Through the sensor element, the formation of the fluid chamber can be monitored in real time during the manufacturing process, and the size of the fluid chamber can be precisely controlled.

According to the above object, the present invention provides a fluid ejection device with a sensor, comprising: a substrate; a structural layer disposed on the substrate and forming a fluid chamber with the substrate; at least one bubble generating device disposed on the structural layer upstream The corresponding side of the body cavity; at least a linear resistance sensor connected to the fluid cavity; a protective layer covering the bubble generating device and the linear resistance sensor; and a nozzle hole adjacent to the bubble generator and penetrating the protective layer and the structural layer, and in contact The fluid chambers are in communication.

According to the above object, the present invention also provides a fluid ejection device with a sensor, comprising: a substrate; a structural layer disposed on the substrate and forming a fluid chamber with the substrate; at least one bubble generating device disposed on the structural layer The corresponding side of the upper fluid chamber; a protective layer covering the bubble generating device; and a spray hole adjacent to the bubble generator and penetrating the protective layer and the structural layer, and communicated with the fluid chamber; and a thin-shell capacitive sensor disposed on the structural layer on, embedded in the protective layer and surrounding the nozzle hole.

According to the above object, the present invention further provides a method for manufacturing a fluid ejection device, comprising the following steps: providing a substrate; forming a patterned sacrificial layer on the substrate; forming a resistor on the sacrificial layer, having a first terminal and A second end; forming a patterned structural layer on the base, covering the patterned sacrificial layer and the resistor, exposing the first end and a second end of the resistor; and forming a fluid channel on the bottom of the substrate to expose a sacrificial layer; and removing the sacrificial layer to form a fluid cavity.

Description of drawings

The following describes the present invention in more detail in conjunction with the accompanying drawings and preferred embodiments.

1 is a schematic cross-sectional view showing a prior art monolithic fluid injection device;

2A and 2B are schematic cross-sectional views showing the fabrication process of the fluid ejection device with sensors according to the first embodiment of the present invention;

FIG. 2C is a schematic cross-sectional view showing the fluid ejection device with sensors according to the first embodiment of the present invention after being filled with ink;

3A and 3B are schematic cross-sectional views showing the fabrication process of a fluid ejection device with a sensor according to a second embodiment of the present invention;

3C is a schematic cross-sectional view showing a fluid ejection device with a sensor according to a second embodiment of the present invention after being filled with ink;

4A is an equivalent circuit diagram showing that the sensor circuit according to an embodiment of the present invention is a filling fluid (length L) connected in series with a linear resistor;

4B is a circuit diagram showing that the sensor circuit of the second embodiment of the present invention is designed as a Wheatstone bridge;

5 is a top view showing a fluid ejection device with a sensor according to a third embodiment of the present invention;

6A and 6B are schematic cross-sectional views showing the fabrication process of a fluid ejection device with a sensor according to a third embodiment of the present invention along the direction of arrow I-I' in FIG. 5;

6C is a schematic cross-sectional view showing a fluid ejection device with a sensor according to a third embodiment of the present invention after being filled with ink;

7A is a schematic structural view showing a thin shell capacitive sensor according to a third embodiment of the present invention;

Fig. 7B shows that the electrodes of the thin shell capacitive sensor according to the third embodiment of the present invention have a multi-layer structure, which is composed of the resistance material of the heater, the metal layer, and the same material as the contact window; and

FIG. 8 is a diagram showing a sensing circuit including capacitors C ₁ , C ₂ and an arithmetic unit according to a third embodiment of the present invention.

Explanation of reference signs

Part of prior art (Figure 1)

1～monolithic fluid injection device; 10～silicon substrate; 12～structural layer; 14～fluid cavity; 20～first heater; 22～second heater; 26～fluid channel; 30～first air bubble; 32 ~Second bubble.

Part of the present invention (Fig. 2A-Fig. 8)

100, 200, 500～fluid injection device; 101, 201, 501～substrate; 110, 210～sacrificial layer; 120, 120a, 120b, 205, 205a, 205b, 220～linear resistance; 130, 230～structural layer; 135, 235～opening; 140, 240～electric meter; 145, 245～protective layer; 150, 250～fluid channel; 160, 260～fluid chamber; 170, 270～bubble generating device; 171, 271～first heater; 172, 272～second heater; 180, 280～injection hole; L～filling fluid length; R ₁ , R ₂ , R ₃ , R ₄ ～resistance; 510～parallel resistance sensor; 512～sacrificial layer; 514～structure layer; 516～protective layer; 520～fluid channel; 530～fluid cavity; 540～spray hole; 550～thin shell capacitive sensor; 551-555～multilayer conductor structure of electrode of thin shell capacitive sensor; Resistance; 562, 564 ~ wire; C ₁ , C ₂ ~ capacitance.

Detailed ways

The invention provides a fluid ejection device with a sensor and a manufacturing method of the fluid ejection device. That is to provide a fluid ejection device with a sensor, the sensor can show different output electronic signals (such as current) before and after the etching process of the fluid ejection device, and under the state of whether the fluid is filled or not through the preset circuit layout. Or resistance), and the control system can use this to judge whether its etching is complete, or whether it has reached the appropriate fluid driving conditions. In addition to achieving multiple functions through a single sensor element, the present invention can simultaneously monitor the formation of the fluid cavity and detect the liquid position in the fluid cavity. Moreover, the sensor can avoid directly measuring the change of the resistance value of the heater, and the original structure of the heater will not be directly affected during the detection process.

first embodiment

The first embodiment of the present invention provides a fluid ejection device with a single linear resistor and a manufacturing method thereof. 2A and 2B are schematic cross-sectional views showing the fabrication process of the fluid ejection device with sensors according to the first embodiment of the present invention. 2C is a schematic cross-sectional view showing the fluid ejection device with sensors according to the first embodiment of the present invention after being filled with ink.

Referring to FIG. 2A , a substrate 101 is provided, such as a single crystal silicon substrate, and a patterned sacrificial layer 110 is formed on the substrate 101 . The sacrificial layer 110 is made of borosilicate phosphoglass (BPSG), phosphosilicate glass (PSG) or other silicon oxide materials deposited by chemical vapor deposition (CVD). A linear resistor 120 is formed on the substrate 101 to conformably cover the sacrificial layer 110 . The material of the wire resistor 120 includes doped polysilicon layer or other conductive materials. Next, a patterned structural layer 130 is conformally formed on the substrate 101 and covers the patterned sacrificial layer 110 . The structure layer 130 may be formed of a low-stress silicon nitride layer formed by chemical vapor deposition (CVD), and its stress is between 100-200 megapascals (MPa). The structure layer 130 includes two openings 135 exposing two ends of the wire resistor 120 . Apply a voltage difference across the two ends of the wire resistor 120, and use an ammeter 140, such as an ammeter, to directly measure the resistance of the wire resistor 120 or the current passing through the wire.

Next, a bubble generating device 170 is formed on the structural layer 130 . The bubble generating device 170 is preferably a heater made of a resistance layer, wherein the resistance layer is formed by physical vapor deposition (PVD), such as evaporation, sputtering or reactive sputtering, such as HfB ₂ , TaAl , TaN or other resistive materials. Next, a protection layer 145 is formed on the structure layer 130 to cover the air bubble generating device 170 . The protective layer 145 is made of silicon oxide formed by chemical vapor deposition.

In this embodiment, the bubble generating device 170 includes a first heater 171 and a second heater 172 , and the second heater 172 and the first heater 171 are respectively located on opposite sides of the nozzle holes.

Referring to FIG. 2B , the back surface of the substrate 101 is etched by a wet etching method to form a fluid channel 150 and expose the sacrificial layer 110 . Then, the sacrificial layer 110 is removed by etching to form a fluid chamber 160 and then expanded to become the enlarged fluid chamber 160 . According to an embodiment of the present invention, during the process of forming the fluid cavity 160, a voltage difference is applied across the two ends of the linear resistor 120, and a meter 140, such as an ammeter, is used to measure the resistance value of the linear resistor 120 or by current in this line. When the measured current value is contributed by the linear resistor 120, the etching is continued. When the measured current value is contributed by the etching solution, or when the measured current value is zero, the etching step is stopped, and subsequent manufacturing process steps are continued.

In FIG. 2A , the material of the wire resistor 120 is made of polysilicon (Poly-Silicon) or similar conductive materials. The wire resistor 120 is located between the sacrificial layer 110 and the structure layer 130 . If this circuit passes a current I, the voltage signal at both ends of the sensor can be obtained as V. After the sacrificial layer is removed, when the etched silicon substrate 101 is etched with KOH solution to expand the fluid chamber 160, it can be seen from FIG. 2B that the linear resistor 120 will be removed together with the silicon material to form an open circuit 120a. Compared with 120b, the current signal at both ends is close to 0 at this time. In this way, the change of the output signal of the circuit can be used to grasp the etching progress.

2C is a schematic cross-sectional view showing the fluid ejection device 100 with sensors according to the first embodiment of the present invention after being filled with ink. The fluid ejection device 100 of the present embodiment includes a substrate 101, a structural layer 130, a fluid chamber 160, and a channel 150, wherein the structural layer 130 is disposed on the substrate 101, and the fluid chamber 160 is formed between the structural layer 130 and the substrate 101 Between, and the channel 150 is connected with the fluid chamber 160. At least one bubble generating device 170 is disposed on the structural layer 130 corresponding to the fluid cavity 160 . A protection layer 145 is formed on the structure layer 130 and covers the air bubble generating device 170 . A nozzle hole 180 is adjacent to the bubble generating device 130 and penetrates the protective layer 145 to communicate with the structural layer 130 and the fluid cavity 160 .

After the aforementioned etching steps are completed, the structure has formed a complete fluid ejection device 100 . At this time, the fluid (see FIG. 2C ) flowing into the fluid cavity 160 and the nozzle hole 180 through the manifold and the flow channel 150 also contacts the original circuits 120 a and 120 b at the same time. At this point, the sensor circuit can be regarded as a resistive system filled with fluid (length L) and connected in series with the linear resistors 140A, 140b. Assuming that the equivalent resistance of the fluid is Rliq, the voltage V _f across the sensor at this moment is: V _f =I(R ₁ +R _liq +R ₂ ). In the formula, R ₁ and R ₂ are the resistance values of the circuits 120a and 120b, respectively.

In practical applications, the design of the sensor in the present invention is not limited to the above-mentioned resistance circuit, but may also be a capacitance circuit, or a resistance-capacitance hybrid circuit. The set parts can also serve as single or multiple sets of sensing and monitoring elements for different areas in the fluid ejection device. However, for the design of sensor applications, attention should be paid to the conductivity range of the fluid. In addition, when performing etching monitoring, if the sensor output signal can be combined with an appropriate signal processing system, the operation of the etching device can be directly controlled. On the finished device, the sensor can also provide feedback to the drive system of the measured fluid position to avoid the occurrence of "dry fire effect" that can cause damage to the fluid injection device.

second embodiment

The second embodiment of the present invention provides a fluid ejection device with two wire resistors connected in parallel and a manufacturing method thereof. 3A-3B are schematic cross-sectional views showing the fabrication process of the fluid ejection device with sensors according to the second embodiment of the present invention. FIG. 3C is a schematic cross-sectional view showing the fluid ejection device with sensors according to the second embodiment of the present invention after being filled with ink.

The fluid ejection device 200 of the second embodiment of the present invention is designed according to the fluid ejection device 100 of the first embodiment, and the description of the same is omitted here. The difference is that the sensor 200 designed in the second embodiment is a multi-resistor parallel design structure. In the fluid ejection device 200 of FIG. 3A , two sets of linear resistance sensors are included: the first group of linear resistors 205 is disposed between the substrate 201 and the sacrificial layer 210, and the second group of linear resistors 220 is disposed on the sacrificial layer. Between the layer 210 and the structural layer 230 , a protective layer 245 is covered on the uppermost layer. The two sets of sensors are designed to be connected in parallel, or they can be designed as independent circuits. When the current I passes through, the voltage V ₀ can be obtained, which is contributed by the first set of wire resistors 205 and the second set of wire resistors 220 . When the substrate 201 (single crystal silicon wafer) of the fluid injection structure is removed by KOH etching solution (as shown in FIG. 3B ), the circuit of the linear resistance sensor 205 is also partially removed thereupon, leaving a linear resistor 205a and 205b, thereby forming an open circuit. At this time, the current I will only pass through the line of the second set of linear resistors 220 , and the measured voltage will also become V ₁ . When the sacrificial layer is removed and etched again with KOH, the second group of linear resistors 220 will also be removed to form an open circuit (as shown in FIG. 3C ), and the voltage output of the overall circuit becomes 0. . In the same way, when the fluid is filled into the etched area, the output voltage of the sensor will change again with the position where the fluid is filled. At this time, the sensor circuit can be regarded as a resistance system filled with fluid (length L) and connected in series with the linear resistors 205a and 205b. Assuming that the equivalent resistance of the fluid is R _liq , the voltage V _f across the sensor is: V _f =I(R ₁ +R _liq +R ₂ ). In the formula, R ₁ and R ₂ are the resistance values of the circuits 205a and 205b respectively. FIG. 4A is an equivalent circuit diagram showing that the sensor circuit according to an embodiment of the present invention is a filling fluid L connected in series with linear resistors 140A, 140b. Assuming that the equivalent resistance of the fluid is R _liq , the voltage V _f across the sensor is: V _f =I(R ₁ +R _liq +R ₂ ). In addition, the sensor circuit can also be designed as a Wheatstone bridge configuration, as shown in FIG. 4B . In Figure 4B, the voltage difference between V _a and V _b can be expressed as: V _b -V _a =V _i (R ₁ R ₄ -R ₂ R ₃ )/((R ₁ +R ₂ )(R ₃ +R ₄ )). If R _i =R ₂ , the previous formula can be rewritten as: V _b -V _a =0.5V _i (R ₄ -R ₃ )/(R ₃ +R ₄ ). If _R3 is designed to be close to the equivalent resistance of the fluid to be measured, when the circuit of the sensor forms an open circuit (R4 approaches infinity), an input voltage with a pressure difference of about half of V _a and V _b can be obtained ; And when the fluid is filled between the circuits (R ₃ =R ₄ ), the pressure difference between V _a and V _b is about 0. In this way, the change of the input voltage and the output voltage can be used to directly obtain the control of the progress of the etching process and the position measurement after the fluid is filled. For example, at normal temperature, the equivalent resistance of the ink is about 10,000 to 100,000 times higher than the equivalent resistance of a potassium hydroxide (KOH) solution with the same geometric size, a temperature of 60° C., and a weight concentration of 33%. Therefore, through the matching design of different circuits, an appropriate corresponding Wheatstone bridge can be formulated for monitoring the etching progress or ink filling.

third embodiment

The sensor designed in the third embodiment of the present invention is a structure in which multiple resistors are connected in parallel and also includes capacitors. 5 is a top view of a fluid ejection device with sensors 500 according to a third embodiment of the present invention. The first group of sensors 550 is a thin shell capacitive sensor 550 whose direction is parallel to the direction of the future nozzle hole 540 . The second group of sensors 510 is similar to the first and second embodiments, but the location of the wire resistors is different from that of the previous embodiments, and is changed to the edge of the sacrificial layer 512 (as shown in FIG. 6A ).

6A and 6B show a schematic cross-sectional view of a fluid ejection device 500 with a sensor according to a third embodiment of the present invention along the direction of arrow II' in FIG. 5 . FIG. 6C is a schematic cross-sectional view showing the fluid ejection device 500 with sensors according to the third embodiment of the present invention after being filled with ink.

The fluid ejection device 500 of the third embodiment of the present invention is based on the design of the fluid ejection device 200 of the second embodiment, and the similarities are omitted here. The difference is that the sensor designed in the third embodiment includes a hybrid circuit of the thin case capacitive sensor 550 and the parallel resistance sensor 510 . The structure of the thin-shell capacitive sensor 550 is shown in FIG. 7A, and its electrodes are composed of multilayer conductor structures (551-555), including resistance materials (TaAl, TiN, TiW or Pt, etc.) of the heater, metal layers (Al- Si-Cu and Al-Cu), and contact windows (TiW or TiN). Therefore, the manufacturing method is compatible with conventional semiconductor processes. The thin capacitive sensor 550 is embedded in the protection layer 516 , and its central position is the nozzle hole 540 of the fluid ejection device 500 . The parallel resistance sensor 510 is composed of resistors 560a, 560b, and 560c connected in parallel and connected to their terminals by wires 562 and 564. The resistor 560a is arranged at the corner between the sacrificial layer 512 and the structural layer 514, and is partially covered above the sacrificial layer. The devices 560b and 560c are disposed at corners between the sacrificial layer 512 , the structural layer 514 and the substrate 501 .

According to the embodiment of the present invention, the measurement of the capacitance change (dielectric constant change) of the sensor 550 circuit can be used to monitor the nozzle hole fabrication process and fluid filling position control, as shown in FIG. 7A . As described in previous embodiments, the parallel resistance sensor 510 can be used to monitor the etching state of the fluid chamber and the filling state of the fluid in the fluid chamber (see FIG. 6C ).

Figure 8 is a sensing circuit including C ₁ , C ₂ capacitors and an operational amplifier, which can be obtained after cooperating with a non-overlapping circuit (not shown in the figure).

${\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}{{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; in</span>}}<span\; class="notranslate">\; .</span>$

Among them _{, C1} is a thin-shell capacitor with a radius r and a height L (as shown in Figure 7A). This capacitor uses the resistance material (TaAl, TiN, TiW or Pt, etc.) of the original heater, the metal layer (Al-Si- Cu and Al—Cu), and contact windows (TiW or TiN) and other materials (as shown in FIG. 7B ). Assuming that the heights occupied by air and fluid are a and La respectively, the capacitance of the thin-shell capacitor can be expressed as Equation 1:

${\mathrm{<figure-callout\; id="1"\; label="C"\; filenames="A20041008196500141.png"\; state="\{\{state\}\}">C</figure-callout>}}_1=\frac{{\mathrm{\&epsiv;}}_0{\mathrm{\&epsiv;}}_f\mathrm{\&pi;a}(L-a)}{2[{\mathrm{\&epsiv;}}_{0}a+{\mathrm{\&epsiv;}}_f(L-a)]}$ (Formula 1)

In Equation 1, ε ₀ and ε _f represent the dielectric constants of air and fluid, respectively. From the output/input voltage ratio and knowing the design value of C ₂ , C ₁ can be calculated. The dielectric constants ε _f and ε ₀ of the fluid and air, and the height L of the shell capacitor 550 are known, so the air height a and the fluid height La can be obtained through C ₁ . This data can be fed back to the fluid injection system for interpretation, and the time to drive the heating element can be adjusted according to the height of the fluid in the nozzle hole, or as follow-up actions such as whether to perform heating, so as to avoid the "empty burning effect" of the heater , so as to effectively guarantee the life of the fluid injection device.

According to the method disclosed in the present invention, each microfluid ejection device can cooperate with the design of the sensor to monitor the single-stage or multi-stage production process and the fluid filling status in the future. In addition to improving the dimensional accuracy of the fluid injection device, this result can also be used to provide a system that can be used as a test condition for driving fluid injection, so as to avoid the "dry burning effect" and prolong the service life. The design circuit of the same sensor can be used in these two projects, and the effect of reducing the production cost can also be achieved.

The feature and effect of the present invention is to form a fluid ejection device with a sensor. The sensor can not only monitor the progress of the etching process during the production of the spray head, but also measure the position of the fluid after the overall structure is completed by outputting the change of the electronic signal. The former can control the progress of the etching process, instead of subsequent optical or other destructive detection; while the fluid position provided by the latter can be used as a reference for fluid injection. The device of the present invention can be effectively applied to data printing processing of text or image, fuel injection system, medicine injection of biomedical technology and other related or similar systems.

Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Those skilled in the art can certainly make changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be determined by the scope defined in the appended claims.

Claims (21)

1. fluid ejection apparatus with sensor comprises:

One substrate;

One structure sheaf is arranged in the described substrate, and and described substrate between form a fluid cavity;

At least one air Bubble generating apparatus is arranged at the respective side of described the above fluid cavity of structure sheaf;

At least one wire electric resistance sensor is connected with described fluid cavity;

One protective layer covers described air Bubble generating apparatus and described wire electric resistance sensor; And

One spray orifice is close to described bubble generator and penetrates described protective layer and described structure sheaf, and is communicated with described fluid cavity.

2. the fluid ejection apparatus with sensor as claimed in claim 1, wherein said air Bubble generating apparatus comprises:

One primary heater is arranged on the surface of described protective layer to be positioned at the outer mode of described fluid cavity, in order to produce one first bubble in described fluid cavity; And

One secondary heater; be arranged on the surface of described protective layer to be positioned at the outer mode of described fluid cavity; and lay respectively at the opposite side of described spray orifice with described primary heater, in order in described fluid cavity, to produce one second bubble so that the fluid in the described fluid cavity is penetrated.

3. the fluid ejection apparatus with sensor as claimed in claim 1, wherein said structure sheaf are a low stress nitride silicon.

4. the fluid ejection apparatus with sensor as claimed in claim 1, wherein said wire electric resistance sensor comprises a plurality of parallel resistance groups.

5. the fluid ejection apparatus with sensor as claimed in claim 1, wherein when described fluid cavity formed, wherein said wire electric resistance sensor is the formation of the described fluid cavity of monitoring in real time, and is etched excessively to avoid described structure sheaf.

6. the fluid ejection apparatus with sensor as claimed in claim 1, wherein when described fluid cavity was filled a fluid, described wire electric resistance sensor became a series connection resistor group with described fluid.

7. fluid ejection apparatus with sensor comprises:

One substrate;

One structure sheaf is arranged in the described substrate, and and described substrate between form a fluid cavity; At least one air Bubble generating apparatus is arranged at the respective side of described the above fluid cavity of structure sheaf;

One protective layer covers described air Bubble generating apparatus; And

One spray orifice is close to described bubble generator and penetrates described protective layer and described structure sheaf, and is communicated with described fluid cavity; And

One shell capacitance sensor is located on the described structure sheaf, is embedded in the described protective layer and around described spray orifice.

8. the fluid ejection apparatus with sensor as claimed in claim 7, wherein said shell capacitance sensor has a pair of arc-shaped electrode.

9. the fluid ejection apparatus with sensor as claimed in claim 8, wherein said arc-shaped electrode are a multi-layer conductive electrode.

10. the fluid ejection apparatus with sensor as claimed in claim 9, the material of wherein said multi-layer conductive electrode comprise TaAl, TiN, TiW, Pt, Al-Si-Cu alloy or Al-Cu alloy.

11. the fluid ejection apparatus with sensor as claimed in claim 7, wherein when described fluid cavity is filled a fluid, described fluid borrows capillarity to be filled in the described spray orifice, described shell capacitance sensor is measured the height of described fluid in described spray orifice, and drives the time of calandria according to the Height Adjustment of described fluid in described spray orifice.

12. the fluid ejection apparatus with sensor as claimed in claim 7 wherein also comprises at least one wire electric resistance sensor, is connected with described fluid cavity.

13. the preparation method of a fluid ejection apparatus comprises the following steps:

One substrate is provided;

Form a sacrificial patterned in described substrate;

Form a wire electric resistance sensor on described sacrifice layer, have one first end and one second end;

Form a pattern structure layer in described substrate, and cover described sacrificial patterned and described wire electric resistance sensor, expose described first end and described second end of described wire electric resistance sensor;

Form a fluid passage in the bottom of described substrate, to expose described sacrifice layer; And

Remove described sacrifice layer to form a fluid cavity.

14. the preparation method of fluid ejection apparatus as claimed in claim 13, the material of wherein said wire electric resistance sensor comprises polysilicon or conductive material.

15. the preparation method of fluid ejection apparatus as claimed in claim 13, the step that wherein removes described sacrifice layer are with the described sacrifice layer of an etching solution etching.

16. the preparation method of fluid ejection apparatus as claimed in claim 15, the step that wherein removes described sacrifice layer comprise, apply described first end and described second end that a voltage is worse than described wire electric resistance sensor, to measure a current value therebetween.

17. the preparation method of fluid ejection apparatus as claimed in claim 16 wherein when measured current value is entirely described wire electric resistance sensor and contributes, then continues etching step and forms described fluid cavity.

18. the preparation method of fluid ejection apparatus as claimed in claim 16, wherein when measured current value was contributed by described wire electric resistance sensor and described etching solution, the step that then stops etching was finished described fluid cavity.

19. the preparation method of fluid ejection apparatus as claimed in claim 13, wherein said wire electric resistance sensor comprises a plurality of parallel resistance groups.

20. the preparation method of fluid ejection apparatus as claimed in claim 19, wherein said a plurality of parallel resistance group comprises one first resistor at the interface that is positioned at described sacrifice layer and described structure sheaf and one second resistor at the interface that is positioned at described structure sheaf and described substrate.

21. the preparation method of fluid ejection apparatus as claimed in claim 20, the step that wherein removes described sacrifice layer comprises, apply one first end and one second end that a voltage is worse than described parallel resistance group, to measure a current value therebetween, wherein when measured current value is contributed by described first and second resistor, then continue the described sacrifice layer of etching, wherein when measured current value was contributed by described second resistor, described sacrifice layer then stopped etching.

Images