Patent Description:
When mounting a semiconductor chip by the flip chip method, an underfill step is performed to fill a resin <NUM> into a gap between a semiconductor chip <NUM> and a substrate <NUM> and to reinforce a connecting portion <NUM> (see <FIG>) for the purpose of preventing stress, which is generated due to the difference in thermal expansion coefficient between the semiconductor chip and the substrate, from concentrating at the connecting portion and damaging the connecting portion. The underfill step is performed by applying the resin <NUM> in a liquid state along an outer periphery of the semiconductor chip <NUM>, causing the resin <NUM> to be filled into the gap between the semiconductor chip <NUM> and the substrate <NUM> with the capillary action, and then heating the resin <NUM> in an oven, for example, to solidify the resin.

Recently, with further reduction in size and thickness of products, sizes and thicknesses of the semiconductor chip <NUM> and the substrate <NUM> themselves used in the flip chip method have also been reduced. The semiconductor chip <NUM> and the substrate <NUM> having smaller sizes and thicknesses are easier to conduct heat therethrough and are more susceptible to ambient temperature. Therefore, the connecting portion <NUM> is more easily damaged by the stress generated as described above. In such a situation, heating the substrate is proposed to reduce viscosity of the resin and to facilitate the filling of the resin with intent to ensure reinforcement obtained with the underfill step.

For example, Patent Document <NUM> discloses a substrate heating device for heating a substrate by spraying heated gas, the substrate heating device comprising a heating unit including a projection that projects upward toward a bottom surface of the substrate, and further including a gas flow path having one end in communication with a blow-off hole opened at an upper surface of the projection and the other end in communication with a gas supply unit; gas heating means heating gas that flows in the gas flow path; an on-off valve turning on or off a flow of the gas supplied to the gas flow path; and a valve control unit controlling opening and closing operations of the on-off valve to heat the substrate to a target temperature.

In the substrate heating device in which the substrate is heated only during the application, however, because the substrate is in a non-heated state when it is conveyed before and after the application, temperature change between during the application and during the conveyance is increased, and change of the above-described stress generated due to the difference in thermal expansion coefficient is also increased. This raises a problem that the connecting portion tends to be damaged.

To cope with the above problem, the applicant has proposed a substrate heating device capable of preventing damage of a connecting portion by reducing, during a time span including periods before and after application work, temperature change of a substrate on which a semiconductor chip is placed, the substrate heating device heating, from below, the substrate conveyed in one direction and including a workpiece which is disposed on the substrate and on which the application work is carried out during the conveyance, wherein the substrate heating device includes a heating member that is held in contact with a bottom surface of the substrate, and that includes a flat upper surface heating the substrate and jet openings formed in the upper surface and allowing heating gas to be jetted out therethrough toward the bottom surface of the substrate, and an elevating mechanism that elevates and lowers the heating member (see Patent Document <NUM>).

<CIT> discloses an apparatus for having the features of the preamble of claim <NUM>.

<CIT> discloses an apparatus for discharging droplets. This apparatus has a droplet discharge head and an air cooling unit for cooling electronic parts in the droplet discharge head.

<CIT> discloses an adhesive extractor. In this adhesive extractor, adhesive filled in a container of the adhesive extractor is effected. A temperature control block is provided surrounding the ejection portion of the container by a thermoelectric conversion element to heat or cool the adhesive.

Because characteristics, such as viscosity, of the liquid material are different depending on temperature, the application work is carried out in some cases while the temperature of the liquid material is controlled by the temperature control device.

However, when the application work is carried out on a stage under heating, there is a problem that the temperature control device is excessively heated by radiant heat from the stage and temperature control is difficult to perform.

Another problem is that, when the application work is carried out at two places where temperature environments are much different from each other, the temperature control device cannot be adapted for the temperature environments and variations generate in discharge amount. For instance, when the application work is carried out on a stage heated to high temperature and a discharge amount is then measured by a weighting device outside the stage, there is a problem that discharge on the stage cannot be reproduced in the weighting device and accurate correction cannot be performed.

In view of the above-described situations, an object of the present invention is to provide a device and a method with which application work can be carried out without causing variations in discharge amount while temperature of a liquid material is adjusted by a temperature control device, even when the application work is performed in two or more work environments much different in temperature from one another.

The above object is solve by a liquid material discharge device having the features of claim <NUM>. An application device having this liquid material discharge device is stated in claim <NUM>. An application method using an application device having this liquid material discharge device is stated in claim <NUM>.

Further developments are stated in the dependent claims.

According to the present invention, even when application work is carried out in two or more work environments much different in temperature from one another, the application work can be carried out without causing variations in discharge amount while the temperature of the liquid material is adjusted by the temperature control device.

[<FIG> is an explanatory view referenced to explain an application operation of a known discharge device, and Fig. <NUM>(b) is an blocking radiant heat from the side including the workpiece. The heat shield member may reflect an infrared ray in a particular wavelength range.

In the above-described liquid material discharge device including the heat shield member, the heat shield member may constitute at least part of an inner wall of the heat-exchange flow path.

In the above-described liquid material discharge device including the heat shield member, the heat shield member may have a bottom area equal to or larger than a bottom surface of the temperature control jacket, and may be disposed in a covering relation to the bottom surface of the temperature control jacket when viewed from the bottom surface side.

In the above-described liquid material discharge device including the heat shield member, the heat shield member may include a rising portion covering a lateral surface of the heat-exchange flow path.

In the above-described liquid material discharge device including the heat shield member, an infrared reflection layer made of a metal surface reflecting an infrared ray in a particular wavelength range or a coating film surface reflecting the infrared ray in the particular wavelength range may be formed at a bottom surface of the heat shield member.

In the above-described liquid material discharge device including the heat shield member having the metal surface or the coating film surface, the heat shield member may be made of a material having a higher thermal conductivity than the bottom surface of the temperature control device and may include a heat transfer layer constituting an inner wall of the coolant flow path.

In the above-described liquid material discharge device including the heat transfer layer, the heat shield member may include a heat insulating layer disposed between the heat transfer layer and the bottom surface and made of a material having a higher thermal conductivity than the bottom surface.

In the above-described liquid material discharge device including the heat shield member that includes the heat insulating layer, the heat insulating layer may be made of resin.

In the above-described liquid material discharge device including the heat shield member, the heat shield member may include a plate-like member disposed with a gap interposed between the plate-like member and the bottom surface of the temperature control jacket, and the heat-exchange flow path may be formed by the gap.

In the above-described liquid material discharge device including the heat shield member, the heat shield member may include a first plate-like member disposed with a gap interposed between the first plate-like member and the bottom surface of the temperature control jacket, and a second plate-like member disposed with a gap interposed between the second plate-like member and a bottom surface of the first plate-like member, and the heat-exchange flow path may include an upper heat-exchange flow path formed by a space between the bottom surface of the temperature control jacket and an upper surface of the first plate-like member, and a lower heat-exchange flow path formed by a space between the bottom surface of the first plate-like member and an upper surface of the second plate-like member. The heat shield member may include a communication tube through which the coolant is supplied to the lower heat-exchange flow path, and a communication hole through which the heat-exchange fluid having passed through the lower heat-exchange flow path is supplied to the upper heat-exchange flow path.

In the above-described liquid material discharge device, an infrared reflection layer made of a metal surface reflecting an infrared ray in a particular wavelength range or a coating film surface reflecting the infrared ray in the particular wavelength range may be formed at the bottom surface of the temperature control jacket.

The above-described liquid material discharge device may further comprise a heat-exchange fluid delivery device that supplies the heat-exchange fluid to the heat-exchange flow path.

In the above-described liquid material discharge device including the heat-exchange fluid delivery device, the heat-exchange fluid delivery device may be constituted by an air supply source supplying pressurized air.

In the above-described liquid material discharge device including the heat-exchange fluid delivery device, the heat-exchange fluid delivery device may be constituted by a circulation pump supplying the heat-exchange fluid in a circulating way.

In the above-described liquid material discharge device, the heat-shield temperature control device may include a temperature sensor measuring a temperature of the temperature control jacket, and the discharge control device may control a flow rate of the heat-exchange fluid flowing through the heat-exchange flow path in accordance with a signal from the temperature sensor.

The above-described liquid material discharge device may further comprise a supply flow path through which the liquid material is supplied to the liquid chamber, wherein the heat-transfer temperature control device is disposed in a covering relation to the liquid chamber and the supply flow path.

The above-described liquid material discharge device may further comprise a plunger including a tip portion that is narrower than the liquid chamber and that is disposed in the liquid chamber, and a plunger driver moving the plunger forward and backward, wherein the liquid material discharge device may be a jet discharge device in which the liquid material is discharged in the form of flying droplets from the discharge port by causing the plunger moving forward to collide against a valve seat formed in an inner bottom surface of the liquid chamber, or by stopping the plunger moving forward immediately before colliding against the valve seat.

An application device according to the present invention comprises the above-described liquid material discharge device, a stage on which the workpiece is placed, a heater heating the stage, a relative moving device moving the liquid material discharge device and the stage relative to each other, and a drive control device controlling the relative moving device.

In the above-described application device, the heater may have an ability of heating the stage to temperature higher than a room temperature by <NUM> or more, and the heat-transfer temperature control device may adjust a temperature of the liquid chamber to be kept within a range of ± <NUM> from the room temperature.

An application method according to a first aspect of the present invention is an application method using the above-described application device that includes the heater with the ability of heating the stage to temperature higher than a room temperature by <NUM> or more, wherein the heat-exchange fluid is a coolant at temperature not higher than the room temperature, and the liquid material is applied in a state in which the stage is heated by the heater to temperature higher than the room temperature by <NUM> or more.

An application method according to a second aspect of the present invention is an application method using the above-described liquid material discharge device, wherein the application method comprises a first application step of performing first application under a first temperature environment, and a second application step of performing second application under a second temperature environment that is different in temperature from the first temperature environment by <NUM> or more.

An application method according to a third aspect of the present invention is an application method using the above-described application device, wherein the application method comprises a step of performing first application on the stage under heating, and a step of performing second application outside the stage.

Operation of the discharge device <NUM> according to the present invention will be described below with reference to <FIG>.

<FIG> is an explanatory view referenced to explain an application operation of a known discharge device <NUM>. The known discharge device <NUM> is equipped with a temperature control device <NUM> including a heat source and a heat transfer member for transferring heat from the heat source to a liquid chamber. In the known discharge device <NUM>, application of a liquid material for drawing a desired pattern is performed by discharging the liquid material from a nozzle member <NUM> while a workpiece <NUM> placed on a stage <NUM> and the nozzle member <NUM> are moved relative to each other. When the stage <NUM> is heated to high temperature (e.g., <NUM> to <NUM>), the temperature control device <NUM> is heated by radiant heat from the stage <NUM> and the workpiece <NUM>. Therefore, if the application operation is performed for a long time, a difficulty occurs in controlling the temperature by the temperature control device <NUM>, and the temperature of the liquid material can no longer be controlled. Thus, there has been a problem (first problem) that, as a result of excessive heating, viscosity of the liquid material is changed and the liquid material cannot be discharged in a desired amount with high accuracy. The first problem becomes more significant especially when the difference in temperature between the stage <NUM> and control temperature of the liquid material exceeds several tens °C. The temperature control device <NUM> corresponds to a heat-transfer temperature control device, described later, in the present invention, and it has a capability of adjusting the temperature of the liquid material, which is discharged from the nozzle member <NUM>, to be kept constant in an environment where the stage <NUM> is not heated. The heat source in the temperature control device <NUM> may have both the functions of heating and cooling, or may have only one of the functions of heating and cooling.

When application work is carried out continuously for a certain time or longer, change in viscosity of the liquid material with the lapse of time has to be taken into consideration. In the underfill step, for example, if the viscosity increases, a discharge amount from a material discharge port decreases and the capillary action becomes insufficient, thus causing a problem that an appropriate amount of the material cannot be filled into the above-described gap. To cope with such a problem, it has been required to move the discharge device <NUM> to a position above a weighing device outside the stage, to measure the weight of the liquid material discharged for a certain time, and to correct change of the discharge amount attributable to the viscosity change with the lapse of time.

However, when the discharge device <NUM> is moved to the position outside the stage where there is no radiant heat, the temperature of the liquid material is lowered, thus causing a problem (second problem) that the discharge amount cannot be measured under the same condition as that on the stage.

Heating the weighing device outside the stage is conceivable to solve the second problem, but such a solution raises a problem (third problem) that a pot life of the liquid material is shortened under high temperature. For instance, when an insulating resin added with a thermosetting agent is used for the so-called potting, the usable time of a potting material is shortened because a thermosetting reaction of the thermosetting agent progresses.

<FIG> is an explanatory view referenced to explain an application operation of a discharge device <NUM> according to the present invention. The discharge device <NUM> includes a heat shield member <NUM> disposed between a stage <NUM> and a temperature control device <NUM> (heat-transfer temperature control device), and a heat-exchange flow path (coolant flow path) <NUM> for heat exchange with the temperature control device <NUM>. Thus, the discharge device <NUM> according to the present invention is featured in including, in addition to the heat-transfer temperature control device <NUM>, a heat-shield temperature control device (<NUM>, <NUM>) disposed between the heat-transfer temperature control device <NUM> and a workpiece <NUM>. In the following, the heat-transfer temperature control device and the heat-shield temperature control device constituted integrally with each other is called a temperature control device unit <NUM> in some cases. Although <FIG> illustrates a heat-shield temperature control device including both the heat shield member <NUM> and the heat-exchange flow path <NUM>, the heat-shield temperature control device may be constituted as a device including either one of the heat shield member <NUM> and the heat-exchange flow path <NUM>. The discharge device <NUM> according to the present invention has an advantageous effect that, because radiant heat from the stage <NUM> and the workpiece <NUM> is blocked off by the heat shield member <NUM>, the temperature control device <NUM> can be prevented from being heated excessively. When the discharge device <NUM> is used for a long time, the heat shield member <NUM> is also heated by the above-mentioned radiant heat, and the temperature control device <NUM> is further heated by radiant heat from the heat shield member <NUM>. However, because the heated temperature control device <NUM> is cooled by heat exchange with a coolant passing through the coolant flow path <NUM>, the temperature control device <NUM> can be prevented from coming into a state being difficult to perform control due to excessive heating even when the application work is carried out for a long time on the stage <NUM> that is heated to high temperature. In addition, the coolant further acts to reduce the radiant heat from the heat shield member <NUM> by cooling the heat shield member <NUM> (namely, the above-mentioned first problem is solved).

Moreover, because the temperature of the liquid material in a liquid chamber <NUM> is adjusted to a level near a room temperature, the discharge amount can be measured by the weighing device outside the stage under the same conditions as those on the stage (namely, the above-mentioned second problem is solved), and the problem of shortening of the pot life does not occur (namely, the above-mentioned third problem is solved). Depending on uses, a heating medium for heating the temperature control device <NUM> may be supplied to flow through the heat-exchange flow path <NUM> in the present invention. A heat exchange fluid supplied to flow through the heat-exchange flow path <NUM> may be gas or a liquid on a case-by-case basis.

The discharge device <NUM> according to the first embodiment of the present invention, illustrated in <FIG>, includes a discharge device main body <NUM>, a nozzle member <NUM>, a switching valve <NUM>, air supply sources 19a to 19c, a storage tank <NUM>, the temperature control device unit <NUM>, and a discharge control device <NUM>.

The nozzle member <NUM> is a tubular member and has a discharge port opened downward. The nozzle member <NUM> is inserted into a lower end portion of the discharge device main body <NUM> and is in fluid communication with the liquid chamber <NUM>.

As illustrated in <FIG>, a valve member <NUM> is inserted into the liquid chamber <NUM>. When the valve member <NUM> departs away from a valve seat <NUM> formed in an inner bottom surface of the liquid chamber <NUM>, the nozzle member <NUM> and the liquid chamber <NUM> are communicated with each other, thus allowing a liquid material to be discharged, and when the valve member <NUM> is seated against the valve seat <NUM>, the communication between the nozzle member <NUM> and the liquid chamber <NUM> is cut and the discharge of the liquid material is stopped. A piston <NUM> air-tightly dividing a piston chamber <NUM> into two parts is disposed in a rear end portion (upper portion) of the valve member <NUM>, and the piston <NUM> is biased downward by a spring <NUM>. When the switching valve <NUM> takes a first position at which a lower space of the piston chamber <NUM> and the air supply source 19a are communicated with each other, pressurized air regulated to an appropriate pressure level by a pressure reducing valve 20a is supplied to the lower space of the piston chamber <NUM>, and the piston <NUM> is moved upward. When the switching valve <NUM> takes a second position at which the lower space of the piston chamber <NUM> and an outlet port 21a are communicated with each other, the air in the lower space of the piston chamber <NUM> is expelled out and the piston <NUM> is moved downward by resilient force of the spring <NUM>. At the first position, the liquid material is discharged because the discharge port and the liquid chamber <NUM> are communicated with each other. At the second position, the discharge of the liquid material is stopped because the communication between the discharge port and the liquid chamber <NUM> is cut.

The liquid chamber <NUM> formed in a lower portion of the discharge device main body <NUM> is in communication with a supply flow path <NUM> through an opening that is formed in an upper lateral surface of the liquid chamber <NUM>. An opening of the supply flow path <NUM> on the opposite side to the liquid chamber <NUM> is in communication with a liquid feed tube <NUM>, and the liquid material <NUM> in the storage tank <NUM> is supplied to the supply flow path <NUM> through the liquid feed tube <NUM> that is connected to a pipe <NUM>. Pressurized air supplied from the air supply source 19c and regulated to an appropriate pressure level by a pressure reducing valve 20b is supplied to an upper space of the storage tank <NUM>.

As illustrated in <FIG> and <FIG>, the liquid chamber <NUM> is surrounded by the temperature control device unit <NUM>, and a temperature of the liquid material in the liquid chamber <NUM> is adjusted to a level optimum for the discharge (the temperature control device unit <NUM> is not illustrated in <FIG>). The temperature control device unit <NUM> includes a heat source (not illustrated) and a temperature control jacket <NUM> both functioning as the heat-transfer temperature control device, and the heat shield member <NUM> and the coolant flow path <NUM> both functioning as the heat-shield temperature control device. With the provision of the temperature control device unit <NUM>, even above the stage under heating, the temperature of the liquid material can be controlled to a level (e.g., <NUM> to <NUM>) near the room temperature or within a range of the room temperature ± <NUM>. It is to be noted that, at a position outside the stage under heating, the temperature of the liquid material can be controlled to be kept within the desired temperature range only by the heat-transfer temperature control device.

As illustrated in <FIG>, the temperature control jacket <NUM> is a rectangular parallelepiped thermally-conductive member that covers a lateral surface and a bottom surface of a portion (lower end portion) of the discharge device main body <NUM> in which the liquid chamber <NUM> is formed, and that has a recess opened at a top. The temperature control jacket <NUM> is made of a material having a high thermal conductivity, such as metal, for transferring heat from a heat source (not illustrated), such as a heater or cold air, to the liquid chamber <NUM>. The temperature control jacket <NUM> may have a structure in which there is no space between the heat source and itself, or a structure in which there is a space between the heat source and itself, the space allowing a heat-exchange fluid to pass therethrough. However, even when the temperature control jacket <NUM> is constituted in the structure having the space through which the heat-exchange fluid passes, the space is to be designed as an independent space with respect to the heat-exchange flow path (coolant flow path) <NUM> in the heat-shield temperature control device (namely, the heat-exchange fluid for the heat-transfer temperature control device and the heat-exchange fluid for the heat-shield temperature control device are to be not mixed with each other) from the viewpoint of avoiding, for example, the problem that control is complicated. The temperature control jacket may have any suitable shape different from that of the illustrated temperature control jacket <NUM>. In an alternative example, the temperature control jacket may be constituted so as to cover only the bottom surface of the portion (lower end portion) of the discharge device main body <NUM> in which the liquid chamber <NUM> is formed, or to cover only the lateral surface of the portion (lower end portion) of the discharge device main body <NUM> in which the liquid chamber <NUM> is formed.

The heat shield member <NUM> is a rectangular plate-like member disposed under the temperature control jacket <NUM> with a gap kept therebetween. The heat shield member <NUM> is preferably made of a material (e.g., resin) having a low thermal conductivity. Lengths of a longitudinal side and a transverse side of the heat shield member <NUM> are equal to or longer than those of a longitudinal side and a transverse side of a bottom surface of the temperature control jacket <NUM>. A positional relation between the heat shield member <NUM> and the temperature control jacket <NUM> is such that, when viewed from the bottom surface side, the temperature control jacket <NUM> cannot be seen because it is blocked by the heat shield member <NUM>. The heat shield member <NUM> may have any desired shape without being limited to the illustrated one.

The bottom surface of the heat shield member <NUM> has the function as an electromagnetic-wave reflection surface that reflects an infrared ray (particularly a far-infrared ray of <NUM> to <NUM>, also called a heat ray) radiated from the stage <NUM> and the workpiece <NUM>. The bottom surface of the heat shield member <NUM> is constituted as a metal surface (made of, e.g., SUS (stainless steel) or a plating of silver or aluminum) that has high infrared reflection efficiency and includes no irregularities, or as a coating film surface that is formed by coating a paint reflecting the infrared ray and includes no irregularities. The bottom surface of the heat shield member <NUM> is preferably finished to a mirror surface. Although, in this embodiment, the heat shield member <NUM> has a size covering the entire bottom surface of the temperature control jacket <NUM>, the heat shield member <NUM> may have a size covering a half or more (preferably <NUM>/<NUM> or more and more preferably <NUM>/<NUM> or more) of the entire bottom surface of the temperature control jacket <NUM>.

The coolant flow path <NUM> is a closed space sandwiched between the bottom surface of the temperature control jacket <NUM> and an upper surface of the heat shield member <NUM>, and a wall <NUM> is disposed at a lateral surface of the coolant flow path <NUM>. A partition wall <NUM> extends from one of four sides defining the wall <NUM> up to near a center, and a discharge hole <NUM>, which is a through-hole, is formed in a tip of the partition wall <NUM>. Projections or recesses may be formed on or in the bottom surface of the temperature control jacket <NUM> and surfaces of the wall <NUM> and/or the partition wall <NUM>, the surfaces coming into contact with the coolant, to increase a surface area and hence to increase efficiency of the heat exchange. When the temperature control jacket <NUM> is constituted, unlike the illustrated form, so as to cover only the lateral surface of the portion (lower end portion) of the discharge device main body <NUM> in which the liquid chamber <NUM> is formed, the coolant flow path <NUM> is constituted by a closed space that is sandwiched between a bottom surface of the lower end portion of the discharge device main body <NUM> and the upper surface of the heat shield member <NUM>.

<FIG> is a sectional view taken along A-A in <FIG>. The coolant flow path <NUM> is in communication with a coolant supply port <NUM> and a coolant outlet port <NUM>. The coolant supplied from the coolant supply port <NUM> passes through the coolant flow path <NUM> while performing heat exchange, and it is then expelled out from the coolant outlet port <NUM>. With the provision of the partition wall <NUM>, the coolant supplied from the coolant supply port <NUM> reaches the coolant outlet port <NUM> through a path denoted by arrows. The partition wall <NUM> prevents the coolant from reaching the coolant outlet port <NUM> through the shortest path, thereby increasing efficiency of the heat exchange.

<FIG> is an enlarged front view of principal part of the discharge device <NUM> according to the first embodiment. A supply joint <NUM> is coupled to the coolant supply port <NUM> of the temperature control device unit <NUM>, and an outlet joint <NUM> is coupled to the coolant outlet port <NUM>. A pressure reducing valve 20c, a flow control valve <NUM>, and an on-off valve <NUM> are disposed (though not illustrated in <FIG>) in a tubing line <NUM> that communicates the air supply source 19b and the supply joint <NUM> with each other. In the first embodiment, because it is desired to control the liquid chamber <NUM> to be held at the room temperature (e.g., <NUM> to <NUM>), the air supply source 19b for pressurizing and supplying outside air is utilized as a coolant delivery device (heat-exchange fluid delivery device). The pressurized air supplied from the air supply source 19b is regulated to an appropriate pressure level by the pressure reducing valve 20c, is adjusted to a desired flow rate by the flow control valve <NUM>, and is supplied to the coolant flow path <NUM> through the on-off valve <NUM>. Thus, the pressurized air functions as the coolant. It is to be noted that, in the first embodiment, the on-off valve <NUM> is always kept in an on-state during the work using the discharge device <NUM>.

Each of the air supply sources 19a to 19c is constituted by a compressor or a cylinder installed in a factory, for example, and is connected to a tubing line, which is in communication with a supply destination, through a removable connector (not illustrated).

The outlet joint <NUM> is in communication with an outlet port 21b through a tubing line <NUM>. The pressurized air having passed through the coolant flow path <NUM> is expelled out from the outlet port 21b through the outlet joint <NUM> and the tubing line <NUM>.

<FIG> is a horizontal sectional view of the temperature control device unit <NUM> according to the first embodiment. The temperature control jacket <NUM> includes a discharge-portion insertion opening <NUM> through which the lower end portion of the discharge device main body <NUM> is inserted. An inner wall surface of the discharge-portion insertion opening <NUM>, which is brought into contact with the discharge device main body <NUM>, is preferably made of a material (e.g., metal) having a high thermal conductivity. More preferably, the entirety of the temperature control jacket <NUM> is made of the material (e.g., metal) having the high thermal conductivity.

The discharge hole <NUM>, which is a through-hole, is formed at a center of the discharge-portion insertion opening <NUM>, and the nozzle member <NUM> is inserted through the discharge hole <NUM>. The coolant supply port <NUM> and the coolant outlet port <NUM> are disposed near one of four sides defining the discharge-portion insertion opening <NUM>, and a temperature sensor <NUM> is disposed near another side. A fin-shaped heatsink <NUM> is disposed along a lateral surface of the temperature control jacket <NUM> with a Peltier element <NUM> interposed therebetween, thus dissipating heat of the temperature control jacket <NUM> to the outside. In other words, in this embodiment, the temperature control device <NUM> is constituted by a heat source, which is made up of the Peltier element <NUM> and the heatsink <NUM>, and by the temperature control jacket <NUM>. An electric fan may be disposed in association with the heatsink <NUM> though not disposed in this embodiment.

The temperature sensor <NUM> is a thermocouple or a resistance thermometer, for example. The temperature of the temperature control jacket <NUM>, which is measured by the temperature sensor <NUM>, is sent to the discharge control device <NUM>.

The discharge control device <NUM> is a computer for controlling operations of the switching valve <NUM>, the flow control valve <NUM>, and the on-off valve <NUM>. The discharge control device <NUM> has the function of performing control independently of the heat-transfer temperature control device <NUM> and the heat-shield temperature control device (<NUM>, <NUM>). The discharge control device <NUM> executes temperature control in such a manner that when the temperature of the temperature control jacket <NUM> is determined to be high on the basis of a signal from temperature sensor <NUM>, the discharge control device <NUM> controls the flow control valve <NUM> to increase the flow rate of the coolant, and that when the temperature of the temperature control jacket <NUM> is determined to be within an allowable range, the discharge control device <NUM> controls the flow control valve <NUM> to reduce the flow rate of the coolant. A control method is not limited to particular one. For example, PID (Proportional- Integral-Differential) control, feedback control, or on-off control is used. The number and positions of temperature sensors <NUM> to be arranged are not limited to the illustrated ones, and the temperature sensor <NUM> may be disposed, for example, in or near the coolant flow path. Alternatively, the coolant may be supplied in a constant flow rate at all times or in a varying flow rate without disposing the temperature sensor <NUM>.

<FIG> is a schematic perspective view of an application device <NUM> equipped with the discharge device <NUM> according to the first embodiment.

The application device <NUM> according to the first embodiment includes, on a bench <NUM>, the stage <NUM> on which the workpiece <NUM>, i.e., an application target is placed, a heater (not illustrated) for heating the stage <NUM>, and a set of an X drive device <NUM>, a Y drive device <NUM>, and a Z drive device <NUM> for moving the discharge device <NUM> relative to the workpiece <NUM>.

The XYZ drive devices (<NUM>, <NUM>, <NUM>) are relative moving devices that move the discharge device <NUM> and the stage <NUM> relative to each other in directions denoted by signs <NUM>, <NUM> and <NUM>, respectively. The discharge control device <NUM> for controlling the operations of the above-described discharge device <NUM>, a drive control device <NUM> for controlling the operations of the above-described drive devices (<NUM>, <NUM>, <NUM>), and the heater (not illustrated) are installed inside bench <NUM>. For example, a heater disclosed in Patent Document <NUM> can be used as the heater.

The heater is capable of heating the stage <NUM> to temperature higher than the room temperature by <NUM> to <NUM> or <NUM> to <NUM>, for example.

A space above the bench <NUM> is covered with a cover <NUM> denoted by dotted lines, and the space can be brought into a negative pressure environment by using a not-illustrated vacuum pump, for example. The cover <NUM> may be provided with a door for access to the inside.

With the above-described discharge device <NUM> according to the first embodiment, even when discharge work is carried out on workpieces placed at places where temperatures are much different from one another (e.g., on workpieces subjected to the temperature difference of <NUM> to <NUM> or <NUM> to <NUM>), the discharge work can be carried out without causing variations in discharge amount. Furthermore, since the liquid material <NUM> is not needed to be heated more than necessary, the pot life of the liquid material can be prolonged.

A liquid material discharge device <NUM> according to a second embodiment, illustrated in <FIG>, is different from that according to the first embodiment mainly in including a discharge member <NUM> and a circulation pump <NUM>. In the following, different points from the first embodiment are mainly described, and description of elements common to the first embodiment is omitted.

The discharge member <NUM> is a block-like member constituting the lower end portion of the discharge device main body <NUM> and is made of a material (e.g., metal) having a high thermal conductivity. The discharge member <NUM> may be removably or integrally attached to another portion of the discharge device main body <NUM> (e.g., an upper portion than the illustrated discharge member <NUM>). The liquid chamber <NUM> is formed inside the discharge member <NUM>, and a tip portion of the valve member <NUM>, which is narrower than the liquid chamber, is inserted into the liquid chamber <NUM> (see <FIG>). A lateral peripheral surface of the valve member <NUM> does not contact with an inner surface of the liquid chamber <NUM>, and friction generated during movement of the valve member <NUM> is minimized. Therefore, the valve member <NUM> can be moved at a high speed.

A cap-like nozzle member <NUM> is mounted to an opening formed in a lower end portion of the discharge member <NUM>, and an inner space of the nozzle member <NUM> also constitutes the liquid chamber <NUM>. A through-hole constituting a discharge port <NUM> (see <FIG>) is formed at a center of a bottom portion of the nozzle member <NUM>, and an inner bottom surface of the nozzle member <NUM> near the through-hole constitutes a valve seat. The discharge device <NUM> according to the second embodiment is a jet discharge device of seating type in which the liquid material is discharged in a droplet state from the discharge port <NUM> by causing a tip of the valve member <NUM> moving forward at a high speed to be seated against the valve seat. The discharge device <NUM> may be a jet discharge device of non-seating type in which the valve member <NUM> is abruptly stopped near the valve seat without causing the valve member <NUM> to be seated against the valve seat.

A lower half portion of the discharge member <NUM> and the nozzle member <NUM> are surrounded by the temperature control jacket <NUM>. As in the first embodiment, the temperature control jacket <NUM> transfers heat from a heat source to the liquid chamber <NUM>. As illustrated in <FIG>, the heat shield member <NUM> is disposed under the temperature control jacket <NUM> with a gap interposed therebetween, the gap forming the coolant flow path <NUM>. The heat shield member <NUM>, the coolant flow path <NUM>, and the wall <NUM> have similar structures to those in the first embodiment. The discharge hole <NUM> is in communication with the discharge port <NUM>, and the liquid material discharged from the discharge port <NUM> is discharged to the outside from a lower end opening of the discharge hole <NUM>.

The temperature control device unit <NUM> is in fluid communication with the circulation pump <NUM> (heat-exchange fluid delivery device) through the supply joint <NUM> and the outlet joint <NUM>. A circulation path through which the coolant is supplied to the coolant flow path <NUM> is formed by connecting the supply joint <NUM> and the circulation pump <NUM> to establish fluid communication through the tubing line <NUM>, and by connecting the outlet joint <NUM> and the circulation pump <NUM> to establish fluid communication through the tubing line <NUM>.

The opening in communication with the supply flow path <NUM> is formed in the upper lateral surface of the liquid chamber <NUM>. A liquid feed path having one end in communication with the supply flow path <NUM> and the other end in communication with a storage container <NUM> is formed in a liquid feed member <NUM>. The storage container <NUM> is formed of a commercially available syringe, and an adapter <NUM> is fitted to an upper opening of the storage container <NUM>. The adapter <NUM> is connected to a pressure feed tube <NUM> through which pressurized air is supplied to the storage container <NUM>. The pressure feed tube <NUM> is in communication with an air supply port of an air dispenser <NUM> for supplying the pressurized air that is regulated to an appropriate pressure level in accordance with a setting value.

The discharge control device <NUM> is connected to the air dispenser <NUM>, the switching valve <NUM>, and the circulation pump <NUM> via cables, and it controls operations of those components.

The circulation pump <NUM> delivers the cooled coolant from a delivery port through the tubing line <NUM>, and recovers the coolant, which has been heated with the heat exchange, from a recovery port through the tubing line <NUM>. For example, a displacement pump, such as a diaphragm pump or a plunger pump, may be used as the circulation pump <NUM>. The circulation pump <NUM> includes a cooling device (not illustrated) and delivers again, from the delivery port, the coolant after cooling the heated coolant by the cooling device. The coolant delivered from the circulation pump <NUM> is a fluid, and it may be a gas coolant such as CO<NUM>, or a liquid coolant such as water.

The above-described discharge device <NUM> according to the second embodiment can also provide similar advantageous effects to those obtained in the first embodiment.

In addition, with the discharge device <NUM> according to the second embodiment, the liquid material in the liquid chamber <NUM> can be controlled to temperature higher or lower than the room temperature.

Liquid material discharge devices <NUM> according to third to fifth embodiments, illustrated in <FIG>, are different from that according to the first embodiment only in structure of the coolant flow path <NUM>. In the following, only different points from the first embodiment are described, and description of elements common to the first embodiment is omitted.

<FIG> is a horizontal sectional view illustrating a structure of the coolant flow path <NUM> in the third embodiment, <FIG> is a horizontal sectional view illustrating a structure of the coolant flow path <NUM> in the fourth embodiment, and <FIG> is a horizontal sectional view illustrating a structure of the coolant flow path <NUM> in the fifth embodiment.

The coolant flow path <NUM> in the third embodiment receives the coolant from the coolant supply port <NUM> positioned in a top surface of the coolant flow path <NUM> near one side of the wall <NUM>, and causes the coolant to be expelled out from the coolant outlet port <NUM> positioned in the top surface of the coolant flow path <NUM> near another one side of the wall <NUM> which is farthest away from the coolant supply port <NUM>. The discharge hole <NUM> is formed in a center portion of the coolant flow path <NUM>. The coolant flows substantially as denoted by arrows in the drawing.

The coolant flow path <NUM> in the fourth embodiment receives the coolant from the coolant supply port <NUM> positioned in the top surface of the coolant flow path <NUM> near one side of the wall <NUM>, and causes the coolant to be expelled out from the plurality of coolant outlet ports <NUM> formed in the wall <NUM> farthest away from the coolant supply port <NUM>. The discharge hole <NUM> is formed in a center portion of the coolant flow path <NUM>. The coolant flows substantially as denoted by arrows in the drawing.

The coolant flow path <NUM> in the fifth embodiment receives the coolant from the coolant supply port <NUM> positioned in the top surface of the coolant flow path <NUM> near one side of the wall <NUM>, and causes the coolant to be expelled out from the coolant outlet port <NUM> positioned in the top surface of the coolant flow path <NUM> near another one side of the wall <NUM> which is farthest away from the coolant supply port <NUM>. Seven partition walls <NUM> are disposed between the coolant supply port <NUM> and the coolant outlet port <NUM> such that the coolant reaches the coolant outlet port <NUM> through a long path. Projections or recesses may be formed on or in surfaces of the wall <NUM> and/or the partition walls <NUM> to increase a surface area coming into contact with the coolant. The discharge hole <NUM> is formed in a center portion of the coolant flow path <NUM>. The coolant flows substantially as denoted by arrows in the drawing. The number and layout of the partition walls <NUM> are not limited to the illustrated ones.

The above-described discharge devices <NUM> according to the third to fifth embodiments can also provide similar advantageous effects to those obtained in the first embodiment.

A liquid material discharge device <NUM> according to a sixth embodiment has a similar structure to that according to the second embodiment, illustrated in <FIG> and <FIG>, except for the coolant flow path and the heat shield member, but it is different mainly in including a heat shield member <NUM> equipped with coolant flow paths <NUM> and <NUM> in two layers. In the following, only different points from the second embodiment are described, and description of elements common to the second embodiment is omitted.

As illustrated in <FIG>, the temperature control jacket <NUM> in the sixth embodiment includes, as in the first and second embodiments, the discharge-portion insertion opening <NUM>, the coolant supply port <NUM>, and the coolant outlet port <NUM>, the ports <NUM> and <NUM> being disposed side by side near one of sides defining the discharge-portion insertion opening <NUM>. The heatsink <NUM> is disposed along the lateral surface of the temperature control jacket <NUM> with the Peltier element <NUM> interposed therebetween, thus dissipating heat of the temperature control jacket <NUM> to the outside.

<FIG> is a sectional view taken along B-B in <FIG>. In the liquid material discharge device <NUM> according to the sixth embodiment, a lower plate <NUM> and an upper plate <NUM> are disposed under the temperature control jacket <NUM>. A lower coolant flow path <NUM> is formed between the lower plate <NUM> and the upper plate <NUM>, and an upper coolant flow path <NUM> is formed between the upper plate <NUM> and the bottom surface of the temperature control jacket <NUM>.

The lower plate <NUM> is the same as the heat shield member <NUM> in the second embodiment.

The upper plate <NUM> is a rectangular plate-like member made of a material (e.g., resin) having a low thermal conductivity, and it has the function as an electromagnetic-wave reflection surface that reflects an infrared ray (particularly a heat ray) from the lower plate <NUM> having been heated. At least a bottom surface of the upper plate <NUM> is constituted as a metal surface (made of, e.g., SUS (stainless steel) or a plating of silver or aluminum) that has high infrared reflection efficiency and includes no irregularities, or as a coating film surface that is formed by coating a paint reflecting the infrared ray and includes no irregularities. The bottom surface of the upper plate <NUM> is preferably finished to a mirror surface.

Because an amount of infrared radiation from the lower plate <NUM> is smaller than that from the stage <NUM> and the workpiece <NUM>, a sufficient effect can be obtained even with the upper plate <NUM> having a smaller thickness than the lower plate <NUM>.

The discharge hole <NUM> is formed so as to penetrate through the lower plate <NUM> and the upper plate <NUM>, and the liquid material discharged from the discharge port <NUM> is discharged to the outside from the lower end opening of the discharge hole <NUM>.

<FIG> is a sectional view taken along C-C in <FIG> is a sectional view taken along D-D in <FIG>. The coolant supplied from the coolant supply port <NUM> is supplied to the lower coolant flow path <NUM> through a communication tube <NUM>. Because a partition wall 48a is disposed in the lower coolant flow path <NUM>, the coolant reaches a communication tube <NUM> through a path denoted by arrows in the drawing. After reaching the communication tube <NUM>, the coolant passes through the upper plate <NUM> and reaches the upper coolant flow path <NUM>. Because a partition wall 48b is disposed in the upper coolant flow path <NUM>, the coolant reaches the coolant outlet port <NUM> through a path denoted by arrows in the drawing. Unlike the above case, the coolant may be supplied to flow in a direction toward the lower coolant flow path <NUM> from the upper coolant flow path <NUM>. Projections or recesses may be formed on or in the bottom surface of the temperature control jacket <NUM>, and surfaces of walls 45a and 45b and/or the partition walls 48a and 48b to increase a surface area coming into contact with the coolant.

With the above-described discharge device <NUM> according to the sixth embodiment, since the heat shield member <NUM> including the coolant flow paths <NUM> and <NUM> constituted in two layers is disposed under the temperature control jacket <NUM>, the radiant heat from the stage <NUM> and the workpiece <NUM> can be prevented more effectively. Although, in this embodiment, the lower plate <NUM> and the upper plate <NUM> have a size covering the entire bottom surface of the temperature control jacket <NUM>, they may have a size covering a half or more (preferably <NUM>/<NUM> or more and more preferably <NUM>/<NUM> or more) of the entire bottom surface of the temperature control jacket <NUM>.

A liquid material discharge device <NUM> according to a seventh embodiment, illustrated in <FIG>, is different from that according to the first embodiment in including a heat shield member <NUM> of a three-layer structure and an infrared reflection layer <NUM>. In the following, only different points from the first embodiment are described, and description of elements common to the first embodiment is omitted.

The heat shield member <NUM> in the seventh embodiment includes an infrared reflection layer <NUM> constituting a lowermost layer, a heat insulating layer <NUM> constituting an intermediate layer, and a heat transfer layer <NUM> constituting an uppermost layer.

The infrared reflection layer <NUM> is an electromagnetic-wave reflection surface that reflects an infrared ray (particularly a heat ray) from the stage <NUM> and the workpiece <NUM>, and is constituted as a metal surface (made of, e.g., SUS (stainless steel) or a plating of silver or aluminum) that has high infrared reflection efficiency and includes no irregularities, or as a coating film surface that is formed by coating a paint reflecting the infrared ray and includes no irregularities. A bottom surface of the infrared reflection layer <NUM> is preferably finished to a mirror surface.

The heat insulating layer <NUM> is made of a material (e.g., resin) having a low thermal conductivity and it prevents the temperature control jacket <NUM> from being heated by radiant heat from an upper surface of the heat shield member <NUM> having been heated. The heat insulating layer <NUM> is preferably made of a material having a lower thermal conductivity than the infrared reflection layer <NUM> that corresponds to the bottom surface of the heat shield member <NUM>.

The heat transfer layer <NUM> is made of a material (e.g., steel, aluminum, or silver) having a higher thermal conductivity than the infrared reflection layer <NUM>. In other words, a material having a relatively high thermal conductivity is selected as the heat transfer layer <NUM> in order to preferentially cool the heat transfer layer <NUM> in comparison with the infrared reflection layer <NUM>.

The infrared reflection layer <NUM> formed at the bottom surface of the temperature control jacket <NUM> is an electromagnetic-wave reflection surface that reflects not only an infrared ray (particularly a heat ray), i.e., radiant heat, from the stage <NUM> and the workpiece <NUM>, but also an infrared ray (particularly a heat ray), i.e., radiant heat, from the upper surface of the heat shield member <NUM> having been heated, and is constituted as a metal surface (made of, e.g., SUS (stainless steel) or a plating of silver or aluminum) that has high infrared reflection efficiency and includes no irregularities, or as a coating film surface that is formed by coating a paint reflecting the infrared ray and includes no irregularities. A bottom surface of the infrared reflection layer <NUM> is preferably finished to a mirror surface.

When a high heat-shield effect is not required, the infrared reflection layer <NUM> does not need to be disposed at the bottom surface of the temperature control jacket <NUM>. In such a case, the heat transfer layer <NUM> is preferably made of a material having a higher thermal conductivity than the bottom surface of the temperature control jacket <NUM>.

With the above-described discharge device <NUM> according to the seventh embodiment, since the radiant heat from the stage <NUM> and the workpiece <NUM> are prevented while the heat shield member <NUM> is preferentially cooled, the application work on the stage <NUM> under heating can be performed for a longer time.

The heat shield member <NUM> of the three-layer structure and/or the infrared reflection layer <NUM> in this embodiment may be applied to the first to sixth embodiments as well.

Unlike this embodiment, the heat shield member <NUM> may be constituted by two layers, i.e., the infrared reflection layer <NUM> and the heat transfer layer <NUM>, without disposing the heat insulating layer <NUM>.

A liquid material discharge device <NUM> according to an eighth embodiment, illustrated in <FIG>, is different from that according to the first embodiment in including a heat shield member <NUM> having a larger area than the temperature control jacket <NUM>. In the following, only different points from the first embodiment are described, and description of elements common to the first embodiment is omitted.

The heat shield member <NUM> in the eighth embodiment includes a rising portion <NUM> covering an outer lateral surface of the wall <NUM>. A bottom surface and an outer lateral surface of the heat shield member <NUM> have the function as electromagnetic-wave reflection surfaces, and they are each constituted as a metal surface or a coating film surface, which reflects the infrared ray and includes no irregularities, as in the first embodiment.

Since a bottom surface of the heat shield member <NUM> in the eighth embodiment is formed in a size slightly larger than that of the temperature control jacket <NUM>, the effect of preventing the radiant heat from the stage <NUM> and the workpiece <NUM> from reaching the lateral surface of the temperature control jacket <NUM> is increased.

The upper plate <NUM> in the sixth embodiment and/or the heat shield member <NUM> of the three-layer structure in the seventh embodiment may be combined with the larger-area heat shield member <NUM> in this embodiment.

Although the preferred embodiments of the present invention have been described above, the technical scope of the present invention is not limited to the above embodiments. The above embodiments can be variously modified and improved, and those modified and improved embodiments also fall within the technical scope of the present invention.

The present invention can be implemented in various types of devices discharging the liquid material and can be applied to, for example, the plunger type in which the liquid material is discharged by moving, through a desired distance, a plunger sliding within a storage container including a nozzle disposed at its tip while the plunger is held in close contact with an inner surface of the storage container, the screw type in which the liquid material is discharged with rotation of a screw, and the valve type in which desired pressure is applied to the liquid material and discharge of the liquid material is controlled by opening and closing a valve. The present invention provides a more significantly advantageous effect in a liquid material discharge device of the type in which the liquid material is applied by dripping the liquid material from a discharge port, which is opened downward, toward a workpiece that is positioned under the discharge port.

Claim 1:
A liquid material discharge device comprising a discharge port (<NUM>), a liquid chamber (<NUM>) in communication with the discharge port (<NUM>), and a discharge control device (<NUM>) adapted to control a discharge operation, the liquid material discharge device (<NUM>) being adapted to discharge the liquid material from the discharge port (<NUM>) while a workpiece (<NUM>) and the discharge port (<NUM>) are moved relative to each other,
wherein the liquid material discharge device (<NUM>) further comprises a heat-transfer temperature control device (<NUM>, <NUM>) including a heat source to adjust a temperature of the liquid chamber (<NUM>),
characterized by
a heat-shield temperature control device (<NUM>, <NUM>) disposed between the heat-transfer temperature control device (<NUM>, <NUM>) and a location where the workpiece (<NUM>) is placeable, and adapted to adjust a temperature of the heat-transfer temperature control device (<NUM>, <NUM>),
wherein the heat-shield temperature control device (<NUM>, <NUM>) includes a heat-exchange flow path (<NUM>) through which, in use, a heat-exchange fluid flows.