CN100430228C - Fluid jet device - Google Patents

Abstract

The present invention provides a fluid jetting device which comprises a plurality of M groups of fluid jetting units and a control unit, wherein each fluid jetting unit comprises a plurality of N spray heads, and each spray head is connected with a driving element. The control unit respectively transports a signal to each driving element to cause the M groups of fluid jetting units to simultaneously and respectively drive a spray head. The driving elements corresponding to the spray heads which are not driven are not provided with parasitic bipolar junction transistor to trigger a plurality of spray heads which are not driven.

Description

Fluid ejection apparatus

Technical field

The present invention is particularly to a kind of injection apparatus that prevents that the parasitic bipolar junction transistor is triggered relevant for a kind of fluid ejection apparatus technology.

Background technology

At present fluid ejection apparatus applies to be applied to ink-jet printer (inkjet printer) mostly, or relevant equipment for example facsimile machine and multifunctional paper feeding machine etc.Also can be used as fluid channel (micro-channel) system of biochip (bio-chip).In addition, fluid ejection apparatus also can be used for fuel injection system (fuel injection system), or on the drug injection elements such as (drug delivery system).

Fig. 1 shows the fluid ejection apparatus of single petrochemical industry of No. the 6th, 471,338, a kind of known United States Patent (USP).Utilize that micro electronmechanical (mos field effect transistor (MOSFET) manufacturing process that adds standard semiconductor is in conjunction with made micro-fluid ejecting device 10 for Micro-Electro-Mechanical System, MEMS) system's manufacturing process.As body, and on silicon substrate 38 and field oxide (field oxide) 50, form a structure sheaf 42 with a silicon substrate 38.Between silicon substrate 38, field oxide 50 and structure sheaf 42, form a fluid cavity 14, in order to hold fluid.Fluid cavity 14 connects the fluid storage groove via fluid passage 16.Spray orifice 17 is communicated with fluid cavity 14 between heater 20,22.On structure sheaf 42, be provided with primary heater 20 and secondary heater 22. Heater 20,22 is connected with driving element via signal transmission line 44.Driving element is that a mos field effect transistor (MOSFET) comprises drain electrode (drain) 107, grid (gate) 105, source electrode (source) 106, and drain electrode (drain) 107 is connected with signal transmission line 44.One protective layer 46 covers this fluid ejection apparatus and driving element.

Along with the evolution of technology, the fluid ejection apparatus technology just towards high density arrange, trend development such as porous is launched simultaneously, increase printing effect and take print speed simultaneously into account to reach.Yet, print for the speed of seeking quickness, adopt the matrix form circuit design traditionally, in order to carrying out the effect that a plurality of fluids spray in the time.Integrated circuit (IC) in the fluid ejection apparatus, adopt mos field effect transistor (MOSFET) design, when fluid ejection apparatus is under the porous while spray regime, and when the hole count of launching simultaneously increases to a certain number when above, then can produce its parasitic bipolar junction transistor (parasitic bipolarjunction transistor, the problem that BJT) is triggered.The undesired driving current signal that this phenomenon caused, except that the jeting effect that influences fluid, the thermal energy excessively of its generation also reduces service life to chip.

Based on above-mentioned shortcoming, therefore industry is needed badly and is wanted a kind of ink gun design that prevents that the parasitic bipolar junction transistor is triggered, design and semiconductor fabrication condition via drive circuit, provide each hole to arrange down in high density, correct current waveform when carrying out the fluid injection simultaneously with porous is with the ink-jet quality that reaches.

Summary of the invention

In view of this, the object of the present invention is to provide a fluid ejection apparatus with mos field effect transistor of low doping concentration, design and semiconductor fabrication condition via drive circuit, reduce the junction capacitance of drain electrode to substrate, to avoid the parasitic bipolar junction transistor to trigger not driven shower nozzle, to reach best ink-jet quality.

According to above-mentioned purpose, the invention provides a kind of fluid ejection apparatus, comprise a plurality of M group fluid ejectors, each fluid ejectors comprises a plurality of N shower nozzle, each shower nozzle connects a driving element; And a control module, transmit a signal respectively to each driving element, make in the M group fluid ejectors, respectively drive a shower nozzle simultaneously.Wherein, in the pairing driving element of not driven shower nozzle, no parasitic bipolar junction transistor triggers not driven shower nozzle.

It should be noted; shower nozzle comprises: a structure sheaf; be arranged on the substrate, a fluid cavity; form between this structure sheaf and the substrate, a passage; connect fluid cavity, at least one fluid actuator; be arranged on the structure sheaf and in the opposite side and a spray orifice of fluid cavity, contiguous air Bubble generating apparatus and pierce through the protection layer and structure sheaf, and be communicated with this fluid cavity.

According to above-mentioned purpose, the present invention provides a kind of fluid ejection apparatus in addition, comprise a plurality of M group fluid ejectors, each fluid ejectors comprises a plurality of N shower nozzle, each shower nozzle connects a mos field effect transistor, comprise a drain electrode, a grid, one source pole and a substrate, wherein draining connects shower nozzle via a signal transmission line road, and drain electrode is less than or equal to 1.139 * 10 to the junction capacitance of substrate ^-14(F/ μ m ²); And a control module, transmit a signal respectively to each mos field effect transistor, make in the M group fluid ejectors, respectively drive a shower nozzle simultaneously; Wherein, in the pairing mos field effect transistor of not driven shower nozzle, no parasitic bipolar junction transistor triggers not driven shower nozzle.

Following conjunction with figs. and preferred embodiment are to illustrate in greater detail the present invention.

Description of drawings

Fig. 1 is the generalized section of the fluid ejection apparatus of a kind of known single petrochemical industry of demonstration;

Fig. 2 is for showing the fluid ejection apparatus of the embodiment of the invention;

Fig. 3 is the generalized section of demonstration according to a shower nozzle of the fluid ejection apparatus of the single petrochemical industry of the embodiment of the invention;

Fig. 4 is for showing the matrix form drive circuit schematic diagram of fluid ejection apparatus of the present invention;

Fig. 5 is the schematic diagram of the driving signal of demonstration fluid ejection apparatus of the present invention;

Fig. 6 is the schematic equivalent circuit of demonstration according to the shower nozzle of the fluid ejection apparatus of the embodiment of the invention;

Fig. 7 A and 7B are presented at respectively under the situation under the situation of CS pin " ON ", connect simultaneously less than 9 P-line as long as drive load, and its voltage, electric current just present and be close to perfect square wave;

Fig. 7 C and 7D are presented at respectively under the situation of CS pin " OFF ", its 300 C _Db(P in parallel ₁To P ₁₆The full connection) with 169 C _Db(P in parallel ₁To P ₉The full connection) the overshoot current result of different sizes; And

Fig. 8 is presented under the N-type doping content of normal N-type doping content and-20% and+20% its junction capacity (junction capacitance) size and the quantity of electric charge (I that contributes substrate _D2) relation.]

Known part (Fig. 1)

The 10-fluid ejection apparatus; The 38-silicon substrate; The 42-structure sheaf; The 50-field oxide; The 14-fluid cavity; The 16-fluid passage; The 17-spray orifice; The 20-primary heater; The 22-secondary heater; The 44-signal transmission line; The 106-source electrode; The 105-grid; The 107-drain electrode; The 46-protective layer.

The present invention's part (Fig. 2 to 8)

The 100-fluid ejection apparatus; P ₁To P ₁₆-fluid ejectors; A ₁To A ₁₉-shower nozzle; The 150-control module; The 338-silicon substrate; The 342-structure sheaf; The 350-field oxide; The 314-fluid cavity; The 316-fluid passage; The 317-spray orifice; The 320-primary heater; The 322-secondary heater; The 344-signal transmission line; The 306-source electrode; The 305-grid; The 307-drain electrode; The 346-protective layer; 203,204,205-switch; The 215-MOSFET element; C _Db-drain substrate junction capacity; I _Os-overshoot current.

The specific embodiment

Fig. 2 is for showing the fluid ejection apparatus 100 of the embodiment of the invention.The fluid ejection apparatus of the embodiment of the invention is example explanation the present invention with 300 shower nozzles, but also non-limiting the present invention, other highdensity fluid ejection apparatus also can be used for the present invention.Fluid ejection apparatus 100 comprises M group (for example 16 groups) fluid ejectors P ₁To P ₁₆, each fluid ejectors P ₁To P ₁₆Comprise a plurality of N (for example 19) shower nozzle A ₁To A ₁₉, each shower nozzle A ₁To A ₁₉Connect a driving element (not shown).One control module 150 transmits a signal respectively to each driving element, makes M group fluid ejectors P ₁To P ₁₆In, respectively drive a shower nozzle A simultaneously ₁To A ₁₉, wherein, not driven shower nozzle A ₁To A ₁₉In the pairing driving element, no parasitic bipolar junction transistor triggers not driven shower nozzle.

Fig. 3 is for showing the shower nozzle A according to the fluid ejection apparatus 100 of the single petrochemical industry of the embodiment of the invention ₁Generalized section.Utilize that micro electronmechanical (mos field effect transistor (MOSFET) manufacturing process that adds standard semiconductor is in conjunction with made shower nozzle A for Micro-Electro-Mechanical System, MEMS) system's manufacturing process ₁As body, and on silicon substrate 338 and field oxide (field oxide) 350, form a structure sheaf 342 with a silicon substrate 338.Silicon substrate 338, and field oxide (fieldoxide) 350 and structure sheaf 342 between form a fluid cavity 314, in order to hold fluid.Fluid cavity 314 connects the fluid storage groove via a fluid passage 316.Spray orifice 317 is communicated with fluid cavity 314 between heater 320,322.On structure sheaf 342, be provided with primary heater 320 and secondary heater 322.Heater 320,322 is connected with driving element via a signal transmission line 344.Driving element is that a mos field effect transistor (MOSFET) comprises drain electrode (drain) 307, grid (gate) 305, source electrode (source) 306, and drain electrode (drain) 307 is connected with signal transmission line 344.Via reducing source electrode 306 and 307 the doping content of draining can reduce the junction capacitance of drain electrode to substrate, trigger not driven shower nozzle to avoid the parasitic bipolar junction transistor, to reach best ink-jet quality.The preferable doping content scope in source electrode 306 and 307 the NDDD zone of draining is on the whole between 10 ²⁰To 10 ²¹Atom/cubic centimetre (atoms/cm ³), can control drain electrode the junction capacitance of substrate is less than or equal to 1.139 * 10 ^-14(F/ μ m ²).One protective layer 346 covers this fluid ejection apparatus and driving element.

Fig. 4 is for showing the matrix form drive circuit schematic diagram of fluid ejection apparatus of the present invention.Fig. 5 is the schematic diagram of the driving signal of demonstration fluid ejection apparatus of the present invention.In embodiments of the present invention, fluid ejection apparatus 100 is divided into 16 P groups and (comprises P ₁To P ₁₆), each P group includes 19 addresses again and (comprises A ₁To A ₁₉).For reduce cost the to reach purpose of (cost down) of the signal pin (I/O pads) that reduces outside soft board (TAB), controlled so again 19 addresses (address) are divided by 3 pins (AG1, AG2, AG3) again.Please refer to the matrix form drive circuit figure of Fig. 4, can select arbitrarily to connect which address (A ₁To A ₁₉) and power and give which P group (P ₁To P ₁₆).For example, when we selected to drive fluid ejecting head as Fig. 4, control module 150 can power supply connect (turn on) with switch 203,204,205 for the CS pin, and then the power supply that AG1, AG2, AG3 can be in regular turn is with 19 address (A ₁To A ₁₉) also connection in regular turn of switch.This moment is if A19 is given in power supply, it is AG3 group's A3 pin, and with 215 connections (turn on) of MOSFET (mos field effect transistor) element, and power supply P1, then the heater 209 on the MOSFET element 215 this moment will have that electric current flows through and finish the operation that heating and fluid spray according to the time of setting.

Based on the consideration on the cost, colour on the printer and the shared AG1 of black ink-jet head, AG2, AG3, A ₁To A ₈And P ₁To P ₂₄Pin, then only define as for will drive black or color ink gun the time by a different black or a colored CS pin.Therefore, no matter driving is black or color ink gun, its both can receive the driving voltage of about 12V.And each NMOS (N-channel mos field effect transistor) element 215 all has an equivalent-circuit model as shown in Figure 6, so when the CS pin is turned off (turn off), and if at P ₁To P ₁₆See simultaneously

$\frac{\mathrm{dV}}{\mathrm{dt}}=\frac{12\mathrm{<figure-callout\; id="2"\; label="V"\; filenames="C20051007297100211.png"\; state="\{\{state\}\}">V</figure-callout>}}{2\mathrm{us}}$

Driving voltage/driving time the time, so entire substrate (substrate) will be seen 300 C as shown in Figure 6 _DbBe connected in parallel, and hypothesis substrate (substrate) has a R _bResistance value, as long as flow to the electric current I of substrate (substrate) this moment _D2Excessive, allow itself and R _bProduct greater than the forward bias (V of parasitic NPN BJT _BeTo 0.76V) time, parasitic NPN BJT be triggered (turn on) will be caused.And if charge to the electric charge of substrate (substrate), if not at once by substrate guiding ground connection, then time of being triggered of its parasitic NPN BJT will be elongated, and causes the lifetime of fluid ejection apparatus or burn.The I ' of Fig. 7 A-D and II ' are illustrated respectively under the situation of CS pin " OFF ", its 300 C _Db(P in parallel ₁To P ₁₆The full connection) with 169 C _Db(P in parallel ₁To P ₉The full connection) the overshoot current I of different sizes _Os(overshoot current) result, this causes the be triggered phenomenon of (turn on) of parasitic NPN BJT because of following of different loads (loading).

The I of Fig. 7 A-D and II then illustrate respectively under the situation under the situation of CS pin " ON ", can find out among the figure that its voltage, electric current just present intimate perfect square wave as long as driving load (driving load) connects simultaneously less than 9 P-line.Also find in the experiment if there not to be overshoot I _OsThe electric current of (over shootcurrent) removes to add hot heater 209, except not having unnecessary thermal power consumption, also can keep preferable ink-jet quality.Otherwise, connect its overshoot current I simultaneously greater than 9 P-line as long as drive load (driving load) _OsNot only cause outside the unnecessary thermal power consumption, more serious in influencing its ink-jet quality.In addition, hot carrier effect (hot carrier effect) triggers the contribution that is caused to parasitic NPN BJT and also need list consideration in.

Table 1 explanation is not changing under the N-type doping content, when driving load (driving load) starts simultaneously less than 9 P-line, its drive current can be kept good square wave, and this moment, the drain junction capacitance (drain junction capacitance) of single NMOS (N-channel mos field effect transistor) element 215 can be C _JD=1.139 * 10 ^-14(F/um ²).Table 2 explanation is after the N-type doping content of minimizing 20%, and its driving load (driving load) can increase to 10 P-line and connect and keep good current waveform simultaneously, at this moment C _JD=1.059 * 10 ^-14(F/um ²).Table 3 explanation is after the N-type doping content of increase by 20%, and it drives load (driving load) and will be reduced to and can only connect and keep good current waveform simultaneously by 8 P-line, at this moment C _JD=0.991 * 10 ^-14(F/um ²).Fig. 8 is presented under the N-type doping content of normal N-type doping content and-20% and+20%, and it causes contributing the quantity of electric charge (I of substrate because of the change of junction capacity (junction capacitance) size _D2) also different.But, in order to increase the speed of printing, sometimes must be with (P under 100% load ₁To P ₁₆Connect simultaneously) print, again as can be known by Fig. 6 and table 2,3:

C _db＝C _JD×A _D， $C_{\mathrm{JD}}=\frac{{\mathrm{<figure-callout\; id="0"\; label="C\; j"\; filenames="C20051007297100211.png"\; state="\{\{state\}\}">C</figure-callout>}}_j}{\sqrt{1+\frac{V_{\mathrm{DB}}}{{\mathrm{\&phi;}}_0}}},$ ${\mathrm{<figure-callout\; id="0"\; label="C\; j"\; filenames="C20051007297100211.png"\; state="\{\{state\}\}">C</figure-callout>}}_j=\sqrt{\frac{q{K}_s{\mathrm{\&epsiv;}}_0{\mathrm{<figure-callout\; id="2"\; label="N\; D"\; filenames="C20051007297100211.png"\; state="\{\{state\}\}">N</figure-callout>}}_D}{2{\mathrm{\&phi;}}_0}}$

Wherein, C _JDBe the depletion type electric capacity (Depletion capacitance of the drainjunction) of drain junction, A _DBe the area (Area of the drain junction) of drain junction, φ ₀Be built-in voltage (build-in voltage) that q is 1.602 * 10 ^-19C, ε ₀Be 8.854 * 10 ^-12F/m, K _sBe the dielectric constant (relative permittivity of silicon) of silicon, N _DBe doping content (dopingconcentration).

Therefore, down fixing in driving ink-jet condition (heating voltage, time), desire to make it to drive load (driving load) and meet at P ₁To P ₁₆Start simultaneously, and the C of single MOS switch element _JDLess than 1.139 * 10 ^-14(F/um ²) time, promptly the doping content of NDDD drops to 10 ²⁰To 10 ²¹Atom/cubic centimetre can guarantee (P under this printing speed pattern ₁To P ₁₆Connection simultaneously), all can keep the effect of good drive waveforms by the current waveform of each heater.In addition, the another kind of C that reduces _DbMethod promptly reduce the area (A of its drain region _D).But this method must reduce the distance (contact via topoly-gate) of contact hole to grid, easily causes the problem of its EOS (electric open/short) to take place.

Feature of the present invention and effect

Feature of the present invention and effect are that one has the fluid ejection apparatus of the mos field effect transistor of low doping concentration, design and semiconductor fabrication condition via drive circuit, reduce the junction capacitance of drain electrode, trigger not driven shower nozzle to avoid the parasitic bipolar junction transistor to substrate.In addition, can provide each hole to arrange down in high density, the correct current waveform when carrying out the fluid injection simultaneously with porous is to reach best ink-jet quality.

Though the present invention with preferred embodiment openly as above; right its is not that any those skilled in the art are under the situation that does not break away from the spirit and scope of the present invention in order to qualification the present invention; can change and modification, so protection scope of the present invention is as the criterion with the claim institute restricted portion that is proposed.

Claims (10)

1. fluid ejection apparatus comprises:

M organizes fluid ejectors, each fluid ejectors comprises N shower nozzle, each shower nozzle connects a driving element, this driving element is a mos field effect transistor, comprise a drain electrode. a grid, one source pole and a substrate, wherein this drain electrode connects this shower nozzle via a signal transmission line road; And

One control module transmits a signal respectively to each driving element, makes a plurality of fluid ejectors in this M group fluid ejectors respectively drive a shower nozzle simultaneously;

Wherein, the drain electrode of this driving element is less than or equal to a predetermined value to the junction capacitance of this substrate, makes in pairing this driving element of not driven shower nozzle, and no parasitic bipolar junction transistor triggers these a plurality of not driven shower nozzles.

2. fluid ejection apparatus as claimed in claim 1, wherein the number of M is 1 to 16.

3. fluid ejection apparatus as claimed in claim 1, wherein the number of N is 1 to 19.

4. fluid ejection apparatus as claimed in claim 1, wherein this shower nozzle and this driving element are formed on the single silicon substrate.

5. fluid ejection apparatus as claimed in claim 4, wherein this mos field effect transistor is a N-channel mos field-effect transistor.

6. fluid ejection apparatus as claimed in claim 4 wherein is somebody's turn to do the depletion type capacitor C of drain electrode to the drain junction of this substrate _IDBe less than or equal to 1.139 * 10 ^-14Method/square micron triggers these a plurality of not driven shower nozzles to avoid the parasitic bipolar junction transistor.

7. fluid ejection apparatus as claimed in claim 4, wherein the doping content value in the N type double-diffused drain electrode NDDD zone of this drain electrode and this source electrode is between 10 ²⁰To 10 ²¹Atom/cubic centimetre triggers these a plurality of not driven shower nozzles to avoid the parasitic bipolar junction transistor.

8. fluid ejection apparatus as claimed in claim 1, wherein this shower nozzle comprises:

One structure sheaf is arranged on the described substrate;

One fluid cavity forms between this structure sheaf and this substrate;

One passage connects this fluid cavity;

At least one fluid actuator is arranged on this structure sheaf and in the opposite side of this fluid cavity; And

One spray orifice is close to this fluid actuator and penetrates a protective layer and this structure sheaf, and is communicated with this fluid cavity.

9. fluid ejection apparatus as claimed in claim 8, wherein this fluid actuator is an air Bubble generating apparatus.

10. fluid ejection apparatus as claimed in claim 8, wherein this structure sheaf is a low stress nitride silicon.

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