JP4985336B2 - Ceramic multilayer substrate manufacturing apparatus and ceramic multilayer substrate manufacturing method - Google Patents

Description

The present invention relates to a ceramic multilayer substrate manufacturing apparatus and a ceramic multilayer substrate manufacturing method.

Low temperature co-fired ceramics (LTCC) technology enables the simultaneous firing of a green sheet and a metal, so that an element-embedded substrate incorporating various passive elements between ceramic layers can be realized. In the system-on-package (SOP) mounting technology, in order to reduce the parasitic effect generated in the composite of electronic components and surface-mounted components, this element-embedded substrate (hereinafter simply referred to as an LTCC multilayer substrate) is involved. Manufacturing methods have been intensively developed.

In the manufacturing method of the LTCC multilayer substrate, a drawing step of drawing a pattern of passive elements, wirings, etc. on each of a plurality of green sheets, a crimping step of laminating and crimping a plurality of green sheets having the pattern, and a crimped body And a firing step of collectively firing. In the drawing process of drawing a pattern on a green sheet, a so-called inkjet method is proposed in which conductive ink is discharged as fine droplets in order to increase the density of the pattern (for example, Patent Document 1). . Since the ink jet method uses minute droplets of several picoliters to several tens of picoliters, the pattern can be miniaturized and the pitch can be reduced by changing the ejection position of the droplets.
JP 2005-57139 A

When the droplets ejected using the ink jet method land on the surface of the green sheet, the droplets spread along the surface of the green sheet according to the surface state of the green sheet, the surface tension of the droplet, and the like. Such wetting and spreading of the droplets is a major obstacle to miniaturization and high density of the pattern. Therefore, in the ink jet method, it is studied to promote drying of the droplet immediately after landing by discharging the droplet while heating the green sheet, thereby suppressing wetting and spreading of the droplet.

However, when drawing by heating the green sheet, the evaporation component contained in the conductive ink stagnates on the surface of the green sheet immediately after drawing, so the evaporation component starts to liquefy again as the heated green sheet cools down. As a result, condensation forms on the surface of the grease sheet. As a result, since the surface of the green sheet is contaminated by condensation, the reliability of the LTCC multilayer substrate is greatly impaired.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a ceramic multilayer substrate manufacturing apparatus and a manufacturing method with improved reliability.

An apparatus for producing a ceramic multilayer substrate according to the present invention includes a stage on which a green sheet is placed and scans the green sheet in a predetermined direction, and is provided on a scanning path of the stage, and a conductive ink is directed toward the green sheet. A drawing unit that draws a liquid pattern on the green sheet by discharging droplets, a drying unit that is provided on the scanning path of the stage and that dries the liquid pattern, and the drawing unit draws the liquid pattern. A heating unit that heats the green sheet and continues to heat the green sheet to a predetermined temperature until the drying unit starts drying the liquid pattern.

According to the ceramic multilayer substrate manufacturing apparatus of the present invention, since the green sheet conveyed from the drawing unit to the drying unit is heated by the heating unit, the evaporation component from the liquid pattern is less likely to condense on the surface of the green sheet. . And since the heat source at the time of drawing and the heat source in a conveyance process are common, the rapid temperature fluctuation of a green sheet can be suppressed and the dew condensation on the surface of a green sheet can be suppressed more reliably. Therefore, according to the manufacturing apparatus of the present ceramic multilayer substrate, the reliability of the ceramic multilayer substrate can be improved to the extent that the condensation of the evaporation component is suppressed.

In the ceramic multilayer substrate manufacturing apparatus, the heating unit is configured such that the partial pressure of the evaporation component from the liquid pattern is lower than the saturated vapor pressure on the surface of the green sheet until the drying unit starts drying the liquid pattern. A configuration in which the green sheet is continuously heated so as to be low is preferable.

According to this ceramic multilayer substrate manufacturing apparatus, since the partial pressure of the evaporated component on the surface of the green sheet is lower than the saturated vapor pressure, dew condensation due to the evaporated component evaporated from the liquid pattern can be more reliably suppressed.

In the ceramic multilayer substrate manufacturing apparatus, it is preferable that the heating unit keeps heating the green sheet until the drying unit finishes drying the liquid pattern.
According to this ceramic multilayer substrate manufacturing apparatus, the saturated vapor pressure on the surface of the green sheet is continuously increased, so that dew condensation due to the evaporated components evaporated from the liquid pattern can be more reliably suppressed.

In this ceramic multilayer substrate manufacturing apparatus, the heating unit may be a heater mounted on the stage.
The method for producing a ceramic multilayer substrate according to the present invention includes a step of drawing a liquid pattern on the green sheet by discharging a droplet of conductive ink toward the heated green sheet, and drying the liquid pattern. A step of forming a dry pattern on the green sheet, and a plurality of the green sheets having the dry pattern are stacked and pressure-bonded to form a pressure-bonded body, and the pressure-bonded body is fired to form the ceramic multilayer substrate The green sheet is continuously heated to a predetermined temperature from the time when the liquid pattern is drawn until the drying of the liquid pattern is started.

According to the method for producing a ceramic multilayer substrate in the present invention, the green sheet after the heat drawing is continuously heated, so that the evaporation component from the liquid pattern is hardly condensed on the surface of the green sheet. Therefore, according to the method for manufacturing the ceramic multilayer substrate, the reliability of the ceramic multilayer substrate can be improved by the amount that suppresses the condensation of the evaporation component.

In the method for manufacturing the ceramic multilayer substrate, the partial pressure of the evaporation component from the liquid pattern is lower than the saturated vapor pressure on the surface of the green sheet until the drying of the liquid pattern is started after the liquid pattern is drawn. A configuration in which the green sheet is continuously heated is preferable.

According to this method for manufacturing a ceramic multilayer substrate, since the partial pressure of the evaporated component on the surface of the green sheet is lower than the saturated vapor pressure, condensation due to the evaporated component evaporated from the liquid pattern can be more reliably suppressed.

The method for manufacturing the ceramic multilayer substrate may have a configuration in which the temperature of the green sheet is continuously increased from the drawing of the liquid pattern until the drying of the liquid pattern is started.
According to this method for manufacturing a ceramic multilayer substrate, since the temperature of the green sheet continues to rise, dew condensation due to the evaporated components evaporated from the liquid pattern can be more reliably suppressed.

Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view of a circuit module having a ceramic multilayer substrate manufactured using the ceramic multilayer substrate manufacturing apparatus of the present invention.

In FIG. 1, a circuit module 10 includes a low temperature co-fired ceramics (LTCC) multilayer substrate 11 as a ceramic multilayer substrate, and a semiconductor chip 12 connected to the LTCC multilayer substrate 11.

The LTCC multilayer substrate 11 is a laminate composed of a plurality of LTCC substrates 13. Each LTCC
Each of the substrates 13 is a green sheet sintered body and has a thickness of several tens to several hundreds of μm. Between the layers of each LTCC substrate 13, various internal elements 14 such as a resistance element, a capacitive element, and a coil element, and an internal wiring 15 electrically connected to each internal element 14 are incorporated, and each LTCC substrate 13. In each layer, via wirings 16 each having a stacked via structure or a thermal via structure are formed.

Next, an LTCC multilayer substrate manufacturing apparatus 20 as a ceramic multilayer substrate manufacturing apparatus is shown in FIG.
And it demonstrates according to FIG. FIG. 2 is a diagram schematically showing an LTCC multilayer substrate manufacturing apparatus 20.

In FIG. 2, the LTCC multilayer substrate manufacturing apparatus 20 includes a base 21 extending in one direction,
And a stage 22 mounted on the base 21. The stage 22 places and fixes a laminated sheet TS including a support sheet BS and a green sheet GS laminated on the support sheet BS. The stage 22 is connected to a linear motion mechanism (not shown) provided on the base 21 and receives a driving force of the linear motion mechanism, thereby being predetermined along the longitudinal direction of the base 21 (hereinafter simply referred to as the scanning direction). It moves at a speed and scans the laminated sheet TS in the scanning direction.

The stage 22 incorporates a stage heater 23 for heating the green sheet GS,
The green sheet GS is heated at a desired timing by driving the stage heater 23.

The green sheet GS is a sheet made of a glass ceramic composition containing glass ceramic powder, a binder, and the like. The film thickness of the green sheet GS is several tens of μm when a capacitor element is formed as the internal element 14, and 100 μm to 200 μm in the other layers.
Formed with.

The glass ceramic powder is a powder having an average particle diameter of 0.1 μm to 5 μm. For example, a glass composite ceramic obtained by mixing borosilicate glass with ceramic powder such as alumina or forsterite can be used. As the glass ceramic powder, ZnO-M
BaO, a crystallized glass ceramic using a crystallized glass of gO—Al ₂ O ₃ —SiO ₂ system
-Al ₂ O ₃ -SiO ₂ ceramic powder and _{Al 2 O 3 -CaO-SiO 2} -MgO-B
A non-glass ceramic using ₂ O ₃ ceramic powder or the like may be used.

The binder is an organic polymer that has a function as a binder of the glass ceramic powder and can be easily removed by decomposition in the firing process. As the binder, for example, a binder resin such as butyral, acrylic or cellulose can be used. The binder may be, for example, an adipate plasticizer, dioctyl phthalate (DOP), dibutyl phthalate (D
BP) A plasticizer such as a phthalate ester plasticizer or a glycol ester plasticizer may be contained.

Above the base 21, that is, on the scanning path of the stage 22, a drawing unit 24 for drawing the liquid pattern P made of the conductive ink Ik and a drying for drying the liquid pattern P made of the conductive ink Ik. The unit 25 is disposed in order along the scanning direction.

In the present embodiment, the temperature in the drawing process using the drawing unit 24 that is the temperature of the green sheet GS is referred to as a drawing temperature Tp (see FIG. 5). Further, the temperature of the green sheet GS until the drying of the liquid pattern P is started, that is, the temperature until the green sheet GS reaches just below the drying unit 25, the conveyance temperature Tx (see FIG. 5). Say. Moreover, it is the temperature of the green sheet GS, Comprising: The temperature in the drying process using the drying part 25 is called drying temperature Td (refer FIG. 5).

The drawing unit 24 includes an ink tank 26A for storing the conductive ink Ik, and an ink tank 26.
A droplet discharge head 26B that discharges the conductive ink Ik from A onto the green sheet GS. The ink tank 26A stores the conductive ink Ik composed of a dispersion system of conductive fine particles, and supplies the stored conductive ink Ik to the droplet discharge head 26B at a predetermined pressure. The conductive fine particles are fine particles having a particle diameter of several nm to several tens of nm, such as gold, silver, copper, platinum, palladium, rhodium, osmium, ruthenium, iridium, iron, tin, cobalt, nickel,
A metal such as chromium, titanium, tantalum, tungsten, indium, or an alloy thereof can be used. The dispersion medium may be any medium that uniformly disperses the conductive fine particles,
For example, water or an aqueous system mainly containing water or an organic system mainly containing an organic solvent such as tetradecane can be used.

The droplet discharge head 26 </ b> B includes a plurality of cavities 27 that communicate with the ink tank 26 </ b> A, a plurality of nozzles N that communicate with the cavities 27, and a plurality of pressure generating elements 28 that are coupled to the cavities 27. A plurality of cavities 27, nozzles N, and pressure generating elements 2
Reference numeral 8 denotes a direction orthogonal to the scanning direction, which is arranged over substantially the entire width of the green sheet GS along a direction perpendicular to the paper surface in FIG. 2 (hereinafter simply referred to as the sub-scanning direction). In FIG. 2, one set of the cavity 27, the nozzle N, and the pressure generating element 28 are schematically shown.

Each cavity 27 receives the conductive ink Ik from the ink tank 26 </ b> A, and supplies the conductive ink Ik to the nozzle N communicating with the cavity 27. Each nozzle N is a nozzle having an opening of several tens of μm, and the conductive ink Ik from the ink tank 26A.
To form a gas-liquid interface (meniscus). Each pressure generating element 28 is a piezoelectric element or a capacitive element that changes the volume of the cavity 27 connected to itself, or a resistance heating element that changes the temperature of the cavity 27. When each pressure generating element 28 receives a predetermined drive signal COM (see FIG. 3), the inside of the cavity 27 is pressurized and the meniscus of the nozzle N is vibrated, so that the conductive ink Ik is several picoliters to several picoliters. A droplet D of 10 picoliter is discharged.

When the green sheet GS is scanned directly below the drawing unit 24, the droplets D ejected from the nozzles N land on the surface of the green sheet GS heated to the drawing temperature Tp. The droplet D that has landed on the green sheet GS is thickened at a portion that comes into contact with the green sheet GS by receiving the amount of heat from the green sheet GS, and suppresses its wetting and spreading. Then, the droplet D that has landed on the green sheet GS coalesces with the subsequent droplet D, whereby the conductive ink I
A liquid pattern P made of k is formed.

The drawing temperature Tp is lower than the decomposition temperature of the binder contained in the green sheet GS, and the surface of the droplet D that has landed on the green sheet GS is thickened to cause the droplet D to adhere to the green sheet GS. Any temperature may be used as long as it is fixed on the surface. If the drawing temperature Tp is excessively high, excessive deformation of the green sheet GS, thickening of the conductive ink Ik stored in the nozzle N, and the like are caused. A configuration that is appropriately selected according to the landing accuracy of the droplet D and the evaporation component contained in the conductive ink Ik is preferable.

The liquid pattern P formed on the green sheet GS evaporates an evaporation component such as a dispersion medium by receiving a heat amount corresponding to the drawing temperature Tp. The evaporation component evaporated from the liquid pattern P stagnates in the vicinity of the liquid pattern P and increases the partial pressure of the evaporation component in the vicinity of the liquid pattern P.

The liquid pattern P formed on the green sheet GS moves from the drawing unit 24 directly below the drying unit 25 as the stage 22 is conveyed. The green sheet GS moving from the drawing unit 24 to the drying unit 25 is heated to the conveyance temperature Tx by receiving the amount of heat from the stage heater 23, and increases the saturated vapor pressure of the evaporation component on the surface of the green sheet GS. Thereby, the green sheet GS can suppress dew condensation due to the evaporation component in the process of being conveyed from the drawing unit 24 to the drying unit 25.

The conveyance temperature Tx is a temperature at which the partial pressure of the evaporated component from the liquid pattern P is made lower than the saturated vapor pressure of the evaporated component at least on the surface of the green sheet GS excluding the liquid pattern P.
Note that if the transport temperature Tx is excessively high, excessive deformation of the green sheet GS is caused.
The transport temperature Tx is preferably selected as appropriate according to the density of the liquid pattern P and the evaporation component contained in the conductive ink Ik.

In the drying unit 25, a plurality of lamp heaters 29 extending along the sub-scanning direction are arranged along the scanning direction. Each lamp heater 29 is a light source that irradiates light L for evaporating the dispersion medium of the conductive ink Ik downward.

When the green sheet GS is scanned directly under the drying unit 25, each lamp heater 29 irradiates the green sheet GS with light L, and heats the green sheet GS to the drying temperature Td. The liquid pattern P drawn on the surface of the green sheet GS substantially eliminates evaporation components such as a dispersion medium contained in the liquid pattern P by receiving heat from the green sheet GS heated to the drying temperature Td. Remove, ie dry. It should be noted that the state in which the evaporation component is substantially removed varies in terms of the frequency of pattern peeling, the degree of pattern deformation, and the like, compared to the state in which the evaporation component is completely removed (the state in which there is no evaporation component). It is a state that does not.

The drying temperature Td may be a temperature that is equal to or higher than the drawing temperature Tp and that can substantially remove the evaporation component contained in the liquid pattern P. The drying temperature Td
Is appropriately selected according to the evaporation component contained in the conductive ink Ik and the composition of the green sheet GS. The configuration is preferable.

Next, the electrical configuration of the LTCC multilayer substrate manufacturing apparatus 20 will be described below. FIG. 3 is an electric block circuit diagram showing an electrical configuration of the LTCC multilayer substrate manufacturing apparatus 20.
In FIG. 3, the control device 30 includes a control unit 30 </ b> A that executes various arithmetic processes, and an LTCC.
A storage unit 30B for storing various data and various control programs for manufacturing the multilayer substrate 11
And have. The control device 30 reads various data and various control programs stored in the storage unit 30B, scans the green sheet GS using the stage 22, discharges the droplets D using the drawing unit 24, and performs the drying unit 25. The drying process of the used liquid pattern and the heating process of the green sheet GS using the stage heater 23 are executed.

An input device 31 having various operation switches is connected to the control device 30. The input device 31 inputs various processing conditions for manufacturing the LTCC multilayer substrate 11 to the control device 30. The control device 30 causes the LTCC multilayer substrate manufacturing apparatus 20 to execute various processes based on various processing conditions from the input device 31. The input device 31 inputs dot pattern data PD for causing the control device 30 to perform the ejection process and temperature data HD for causing the control device 30 to perform the heating process.

The dot pattern data PD is data that defines whether or not the droplet D is ejected to each lattice point of the virtual lattice formed on the green sheet GS. That is, dot pattern data PD
Is data for turning on or off the pressure generating element 28 connected to the nozzle N according to the value (0 or 1) of each nozzle when the nozzle N is positioned immediately above the lattice point in the scanning process. .

The temperature data HD is data in which the output of the stage heater 23 is associated with the position of the stage 22. The temperature data HD is data for continuing to heat the green sheet GS positioned on the stage 22 while the stage 22 is positioned directly below the drawing unit 24. The temperature data HD is data for continuing to heat the green sheet GS positioned on the stage 22 until the stage 22 reaches just below the drying unit 25.

A stage drive circuit 32 is connected to the control device 30. The control device 30 inputs a control signal corresponding to the stage drive circuit 32 to the stage drive circuit 32. The stage drive circuit 32 drives the linear motion mechanism in response to a control signal from the control device 30 and executes a scanning process for the stage 22. The stage drive circuit 32 receives a detection signal from an encoder provided in the linear motion mechanism, and outputs a signal related to the conveyance direction and position of the stage 22 (hereinafter simply referred to as a position detection signal) to the control device 30.

A stage heater drive circuit 33 is connected to the control device 30. The control device 30
In response to the position detection signal from the stage drive circuit 32, a heater control signal IH for driving the stage heater 23 is generated based on the temperature data HD, and the heater control signal IH is output to the stage heater drive circuit 33. The stage heater drive circuit 33 drives the stage heater 23 in response to the heater control signal IH from the control device 30 and heats the green sheet GS laminated on the stage 22 to a predetermined temperature.

A drawing unit drive circuit 34 is connected to the control device 30. The control device 30 receives a position detection signal from the stage drive circuit 32, generates a control signal for driving the drawing unit 24, and inputs the control signal to the drawing unit drive circuit 34. That is, the control device 30 inputs the timing signal LT and the drive signal COM to the drawing unit drive circuit 34 each time the discharge position of the droplet D is located immediately below the nozzle N. In addition, the control device 30 performs dot pattern data PD
Is used to generate a discharge control signal SI associated with each nozzle N, and the discharge control signal SI is serially transferred to the drawing unit drive circuit 34 at a predetermined transfer clock. The drawing unit drive circuit 34
Each time the timing signal LT from the control device 30 is received, the discharge control signal SI from the control device 30 is converted from serial to parallel, and a parallel consisting of the value (0 or 1) of each bit associated with each pressure generating element 28. Generate a signal. Each time the drawing unit drive circuit 34 receives the timing signal LT, the drawing unit drive circuit 34 supplies the drive signal COM to the pressure generating element 28 selected by the parallel signal, and discharges the droplets D from the selected nozzles N, respectively. That is, the drawing unit driving circuit 34 draws the liquid pattern P based on the dot pattern data PD on the green sheet GS in the scanning process.

A drying unit driving circuit 35 is connected to the control device 30. The control device 30 receives the position detection signal from the stage drive circuit 32, generates a control signal for driving the drying unit 25, and inputs the control signal to the drying unit drive circuit 35. The drying unit drive circuit 35 drives each lamp heater 29 in response to a control signal from the control device 30 and heats the liquid pattern P immediately below each lamp heater 29.

Next, a manufacturing method of the LTCC multilayer substrate 11 using the LTCC multilayer substrate manufacturing apparatus 20 will be described. FIG. 4 is a flowchart showing a manufacturing process of the LTCC multilayer substrate 11.
FIG. 5 is a time chart showing the temperature of the green sheet GS in each manufacturing process.

When the laminated sheet TS is placed on the stage 22, the control device 30 first drives the stage heater 23 via the stage heater drive circuit 33 to change the temperature of the green sheet GS to the drawing temperature Tp (for example, 60 ° C.). ). Next, the control device 30 drives the stage 22 via the stage drive circuit 32 and starts the scanning process for the green sheet GS. When the scanning process of the stage 22 is started, the control device 30 drives each pressure generating element 28 via the drawing unit driving circuit 34, and each time the discharge position of the green sheet GS is located immediately below the nozzle N, the nozzle 30 is driven. A droplet D is discharged from N, and a liquid pattern P is drawn on the surface of the green sheet GS (drawing step: step S11). As a result, the control device 30 controls the green sheet G.
As much as S is heated to the drawing temperature Tp, wetting and spreading of the liquid pattern P can be suppressed.

When the liquid pattern P is formed, the control device 30 drives the stage heater 23 via the stage heater drive circuit 33 and changes the temperature of the green sheet GS to the conveyance temperature Tx (for example, 70 ° C.).
). And the control apparatus 30 drives the stage 22 via the stage drive circuit 32, and conveys the green sheet GS from the drawing part 24 directly under the drying part 25 (conveying process:
Step S12). Thereby, the control device 30 transfers the green sheet GS to the conveyance temperature Tx.
Thus, the saturated vapor pressure of the evaporation component can be increased on the surface of the green sheet GS by the amount of heating, and condensation due to the evaporation component from the liquid pattern P can be suppressed.

When the control device 30 conveys the green sheet GS directly below the drying unit 25, the control device 30 continues to drive the stage heater 23 via the stage heater drive circuit 33, and each lamp heater 29 via the drying unit drive circuit 35. The green sheet GS immediately under each lamp heater 29 is driven and heated to a drying temperature Td (for example, 80 ° C.) (drying step: step S13).
Thus, the control device 30 can substantially remove the dispersion medium and the like contained in the liquid pattern P, and can fix the liquid pattern P on the surface of the green sheet GS (a dry pattern can be formed). In addition, the control device 30 performs drawing temperature Tp, conveyance temperature Tx, and drying temperature T.
Since the set temperature is increased in the order of d, sudden temperature fluctuations associated with the green sheet GS can be eliminated, and condensation due to the evaporated components evaporated from the liquid pattern P can be more reliably suppressed.

When the drying pattern is formed, the control device 30 drives the stage 22 via the stage driving circuit 32 and carries out the green sheet GS placed on the stage 22 to the outside. And the control apparatus 30 forms the some green sheet GS with a dry pattern by performing the same drawing process, conveyance process, and drying process with respect to the subsequent green sheet GS.

The plurality of green sheets GS carried out from the LTCC multilayer substrate manufacturing apparatus 20 are stacked on another green sheet having a dry pattern and vacuum-sealed in a vacuum packaging bag (reduced pressure packaging step: step S14). The laminated body consisting of a plurality of green sheets GS is carried into a hydrostatic pressure press apparatus in a vacuum-enclosed state, and is crimped by applying hydrostatic pressure (crimping step: step S15). Each pressed green sheet GS is carried into a predetermined firing furnace,
LT is obtained by firing at a predetermined firing temperature (for example, 800 ° C. to 1000 ° C.).
A CC multilayer substrate 11 is formed (firing step: step S16).

Next, the effect of the said embodiment is described below.
(1) In the above embodiment, the green sheet GS is continuously heated to the conveyance temperature Tx from when the liquid pattern P is drawn until the drying of the liquid pattern P is started. Therefore, since the heated green sheet GS is continuously heated, the saturated vapor pressure of the evaporation component from the liquid pattern P can be continuously increased on the surface of the green sheet GS. As a result,
The LTCC multilayer substrate manufacturing apparatus 20 can suppress the condensation on the surface of the green sheet GS, and can improve the reliability of the LTCC multilayer substrate 11 by the amount that suppresses the condensation of evaporation components.

(2) In the embodiment described above, the stage heater 23 heats the green sheet GS to the drawing temperature Tp when drawing the liquid pattern P, and transfers the green sheet GS to the conveyance temperature Tx until the drying of the liquid pattern P is started. Continue to heat. Therefore, since the heat source that realizes the drawing temperature Tp and the heat source that realizes the conveyance temperature are the common stage heater 23,
The temperature of the green sheet GS is adjusted smoothly between processes. As a result, since the rapid temperature fluctuation of the green sheet GS can be suppressed, dew condensation on the surface of the green sheet GS can be more reliably suppressed.

(3) In the above embodiment, the conveyance temperature Tx is a temperature at which the partial pressure of the evaporation component is lower than the saturated vapor pressure on the surface of the green sheet GS excluding at least the liquid pattern P. Therefore, since the partial pressure of the evaporated component on the surface of the green sheet GS is lower than the saturated vapor pressure, condensation due to the evaporated component evaporated from the liquid pattern P can be more reliably suppressed.

(4) In the above embodiment, the temperature is increased in the order of the drawing temperature Tp, the conveyance temperature Tx, and the drying temperature Td. Therefore, until the drying of the liquid pattern P starts, the green sheet GS
Therefore, the dew condensation due to the evaporated components evaporated from the liquid pattern P can be more reliably suppressed.

In addition, you may change the said embodiment as follows.
In the above embodiment, the set temperature is increased in the order of the drawing temperature Tp, the conveyance temperature Tx, and the drying temperature Td. For example, as shown in FIG. 6, the conveyance temperature Tx is changed to the drawing temperature Tp.
Alternatively, the temperature may be lower than the drying temperature Td, or the temperature may be decreased in the order of the drawing temperature Tp, the conveyance temperature Tx, and the drying temperature Td. That is, the transfer temperature Tx is
At least the temperature at which the partial pressure of the evaporation component is lower than the saturated vapor pressure on the surface of the green sheet GS excluding the liquid pattern P may be used.

In addition, when the temperature of the green sheet GS is switched from the drawing temperature Tp to the conveyance temperature Tx,
Alternatively, when the temperature of the green sheet GS is lowered when the conveyance temperature Tx is switched to the drying temperature Td, the green sheet G is sprayed while spraying an inert gas or the like on the green sheet GS.
A configuration in which the temperature of S is gradually lowered is preferable. According to this configuration, since the temperature of the green sheet GS is lowered while reducing the partial pressure of the evaporation component, dew condensation on the surface of the green sheet GS can be suppressed.

In the above embodiment, a suction mechanism may be provided between the drawing unit 24 and the drying unit 25 to suck the evaporation component. According to this configuration, since the partial pressure of the evaporation component can be further reduced, condensation on the surface of the green sheet GS can be avoided more reliably.

In the above embodiment, the green sheet GS directly under the drawing unit 24 is the stage 2
2 is transported to the drying unit 25 by scanning. Not limited to this, the green sheet GS immediately below the drawing unit 24 may be transferred to the support plate and conveyed to the drying unit 25 by another conveyance mechanism, hand, or the like. Any structure may be used as long as the plate continues to heat the green sheet GS.

In the above embodiment, the stage heater 23 continues to heat the green sheet GS even after reaching directly below the drying unit 25. Not limited to this, the stage heater 23 may be configured to stop driving at the timing when each lamp heater 29 heats the liquid pattern P. That is, the heating unit may be configured to continue heating the green sheet until at least drying of the liquid pattern is started.

In the above embodiment, the heating unit is embodied as the stage heater 23, but the heating unit is not limited thereto, and the heating unit may be a heat source such as a lamp heater or a laser provided above the base 21.

Sectional drawing which shows a circuit module. The figure which shows the manufacturing apparatus of a ceramic multilayer substrate. The figure which shows the electrical constitution of the manufacturing apparatus of a ceramic multilayer substrate. The flowchart which shows the manufacturing method of a ceramic multilayer substrate. The figure which shows the temperature of the green sheet in each manufacturing process of a ceramic multilayer substrate. The figure which shows the temperature of the green sheet in each manufacturing process of the ceramic multilayer substrate in the example of a change.

Explanation of symbols

D ... droplet, Ik ... conductive ink, GS ... green sheet, P ... liquid pattern, 11 ... LTCC multilayer substrate as ceramic multilayer substrate, 20 ... LTCC multilayer substrate manufacturing device as ceramic multilayer substrate manufacturing device, 22 ... Stage, 23 ... Stage heater as heating part, 24 ... Drawing part, 25 ... Drying part.

Claims (7)

An apparatus for manufacturing a ceramic multilayer substrate,
A stage for placing the green sheet and scanning the green sheet in a predetermined direction;
A drawing unit that is provided on a scanning path of the stage and draws a liquid pattern on the green sheet by discharging a droplet of conductive ink toward the green sheet;
A drying unit provided on a scanning path of the stage, and drying the liquid pattern by heating the liquid pattern;
Heating the green sheet when the drawing unit draws the liquid pattern; and
A heating unit that continues heating the green sheet to a predetermined temperature until the drying unit starts drying the liquid pattern;
An apparatus for producing a ceramic multilayer substrate. An apparatus for producing a ceramic multilayer substrate according to claim 1,
The heating unit is
Until the drying unit starts to dry the liquid pattern, the green sheet is continuously heated so that the partial pressure of the evaporated component from the liquid pattern is lower than the saturated vapor pressure on the surface of the green sheet. An apparatus for manufacturing a ceramic multilayer substrate. An apparatus for producing a ceramic multilayer substrate according to claim 1 or 2,
The heating unit is
The apparatus for manufacturing a ceramic multilayer substrate, wherein the drying unit continues to heat the green sheet until the drying of the liquid pattern is completed. It is a manufacturing apparatus of the ceramic multilayer substrate according to any one of claims 1 to 3,
The apparatus for manufacturing a ceramic multilayer substrate, wherein the heating unit is a heater mounted on the stage. A method for producing a ceramic multilayer substrate, comprising:
Drawing a liquid pattern on the green sheet by discharging droplets of conductive ink toward the heated green sheet;
Forming a dry pattern on the green sheet by heating and drying the liquid pattern;
Forming a press-bonded body by laminating and press-bonding a plurality of the green sheets having the dry pattern, and forming the ceramic multilayer substrate by firing the press-bonded body,
The method for producing a ceramic multilayer substrate, wherein the green sheet is continuously heated to a predetermined temperature after the liquid pattern is drawn until the drying of the liquid pattern is started. A method for producing a ceramic multilayer substrate according to claim 5,
The green sheet is heated so that the partial pressure of the evaporation component from the liquid pattern is lower than the saturated vapor pressure on the surface of the green sheet from the time when the liquid pattern is drawn until the drying of the liquid pattern is started. A method for producing a ceramic multilayer substrate, comprising: continuing. A method for producing a ceramic multilayer substrate according to claim 5 or 6,
The method for producing a ceramic multilayer substrate, wherein the temperature of the green sheet is continuously increased from the drawing of the liquid pattern until the drying of the liquid pattern is started.

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