KR102481022B1 - Vaporizer system having function of measuring level of precursor stored in canister - Google Patents

Abstract

The present invention relates to a vaporizer system comprising, in one embodiment, a canister capable of storing a precursor; a heater thermally coupled to the canister to vaporize the precursor; a first temperature sensor measuring a temperature of a first point inside the canister; a second temperature sensor measuring a temperature of a second point spaced downward by a predetermined distance from the first point; And a controller that calculates the level of the precursor based on the measured temperatures of the first and second temperature sensors, wherein the controller calculates a difference value (ΔT) between the measured temperatures of the first point and the second point, and A vaporizer system configured to output a level of precursor stored in the canister based on a result of the calculation is disclosed.

Description

Vaporizer system having function of measuring level of precursor stored in canister}

The present invention relates to a vaporizer system, and more particularly, to a vaporizer system having a function capable of measuring the level of a precursor stored in a canister.

Various raw materials (precursors) used in processing equipment such as chemical vapor deposition (CVD) or atomic layer deposition (ALD), which coat essential thin films in the manufacturing process of electronic materials such as semiconductors, displays, and light emitting diodes, are gas, liquid, or Supplied in solid form.

In the case of raw materials in the form of gas, it is used as a method of supplying a certain amount by adjusting the pressure, but in the case of liquid or solid materials, since their own pressure is very low, most of them are put in an ampoule called a canister and used as a carrier gas (inert gas). A method of vaporizing through steam generation through bubbling or heating and then supplying it to the reaction chamber is used.

1 schematically shows a conventional general vaporizer system. Referring to FIG. 1, a general vaporizer system includes a canister 10, a first pipe L1 for transporting a carrier gas to the canister 10, and a processing facility in the canister 10 (eg, a chemical vapor deposition (CVD) device or A second pipe (L2) for transporting gas to a process chamber of semiconductor processing equipment such as an ion implanter), a third pipe (L3) connecting the first pipe (L1) and the second pipe (L2), and each pipe It consists of one or more valves (V1, V2, V3) installed on (L1, L2, L3).

In this configuration, after putting the raw material (precursor) in liquid or solid form into the canister 10, a carrier gas is supplied to the canister 10 through the first pipe L1 to vaporize or sublimate the precursor by a certain amount, and thus vaporize or sublimate the precursor. The sublimated precursor and carrier gas are transported and supplied to the processing facility through the second pipe (L2).

In such a conventional vaporizer system, when all of the precursors filled in the canister 10 are consumed or the remaining amount of the precursor is below a reference value, the canister 10 needs to be replaced. To this end, it is necessary to accurately measure the remaining amount of the precursor stored in the canister 10 there is.

As a conventional technology for measuring the remaining amount of a precursor, a scale is used to measure the weight of the precursor, but this technology often has a problem in that the accuracy of measurement cannot be guaranteed depending on working conditions such as temperature change.

Patent Document 1: Korean Patent Publication No. 2020-0055872 (published on May 22, 2020)

The present invention has been made to solve the above problems, and an object of the present invention is to provide a level measuring device and method capable of measuring the level (surface or water level) of a precursor.

According to one embodiment of the present invention, a vaporizer system comprising: a canister capable of storing a precursor; a heater thermally coupled to the canister to vaporize the precursor; a first temperature sensor measuring a temperature of a first point inside the canister; a second temperature sensor measuring a temperature of a second point spaced downward by a predetermined distance from the first point; And a controller that calculates the level of the precursor based on the measured temperatures of the first and second temperature sensors, wherein the controller calculates a difference value (ΔT) between the measured temperatures of the first point and the second point, and Disclosed is a vaporizer system configured to output a level of precursor stored in the canister based on a calculation result.

According to one embodiment of the present invention, the level of the precursor stored in the canister can be accurately measured. In addition, according to one embodiment of the present invention, it is possible to accurately measure the remaining amount of the precursor stored in the canister without being affected by working environments such as temperature changes.

1 is a diagram illustrating a prior art exemplary vaporizer system;
2 is a view for explaining a canister according to an embodiment of the present invention;
Fig. 3 is a diagram showing a state in which the precursor in the canister decreases in the first embodiment;
4 is a diagram for explaining a precursor level measuring method according to a first embodiment;
Fig. 5 is a diagram showing a state in which the precursor in the canister decreases in the second embodiment;
6 is a diagram explaining a precursor level measuring method according to a second embodiment;
Fig. 7 is a diagram showing a state in which the precursor in the canister decreases in the third embodiment;
8 is a diagram explaining a precursor level measurement method according to a third embodiment.

The above objects, other objects, features and advantages of the present invention will be easily understood through the following preferred embodiments in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed content will be thorough and complete and the spirit of the present invention will be sufficiently conveyed to those skilled in the art.

In this specification, terms indicating positions or directions, such as 'upper', 'lower', 'left', 'right', 'front', 'rear', etc., to describe the positional relationship between components, are positions or directions as absolute standards. It may not mean, and when the present invention is described with reference to each drawing, it may be a relative expression used for convenience of description based on the drawing or the corresponding component.

In this specification, when an element (A) is referred to as being connected (or coupled, fastened, attached, etc.) to another element (B), it means that the element (A) is directly connected to the other element (B), or It means that they are connected indirectly through a third component between them.

In the drawings of this specification, the length, thickness, or width of components are exaggerated for effective description of technical content, and the relative size of one component and another component may also vary depending on specific embodiments.

In this specification, the singular form of a component also includes the plural form unless otherwise specified in the phrase. The expressions 'comprises', 'consists of', and 'consists of' used in the specification do not exclude the presence or addition of one or more other elements in addition to the mentioned elements.

In describing the specific embodiments below, various specific details have been prepared to more specifically describe the invention and aid understanding. However, readers who have knowledge in this field to the extent that they can understand the present invention can recognize that it can be used without these various specific details. In some cases, it is mentioned in advance that parts that are commonly known in describing the invention and are not greatly related to the invention are not described in order to prevent confusion in describing the present invention.

Definition of Terms

In the present specification, 'flow path', 'line', and 'pipe' refer to a transport space in which gas can move.

In the present specification, 'controlling the flow' is a concept including blocking the flow, allowing the flow, or controlling the amount of flow. For example, a component capable of controlling the flow of fluid is a component capable of blocking the flow of fluid, permitting the flow of fluid, or controlling the amount of flowing fluid, and may include a valve or a fluid load.

In the present specification, a 'valve' is a component capable of controlling the flow of fluid, and means a component capable of blocking the flow of fluid, allowing the flow of fluid, or controlling the amount of flowing fluid, for example, on- It may be devices such as off-valves and control valves.

In the present specification, an 'on-off valve' means a valve that blocks the flow of fluid or allows the flow of fluid, and a 'control valve' that blocks or allows the flow of fluid or controls the amount of flowing fluid. means an adjustable valve.

In the present specification, 'upstream' and 'downstream' are terms used to indicate a position in a line ('flow path') through which fluid flows. means that at least some of the fluids reaching component A reach component B first. Also, that component A is located downstream of component B means that the fluid reaches component B first and at least a part of the fluid reaching component B reaches component A.

A vaporizer system according to the present invention is a device that vaporizes a precursor and provides it to a processing facility. The processing facility may be, for example, a device such as a process chamber of semiconductor processing equipment such as a chemical vapor deposition (CVD) device or an ion implanter.

In the present invention, the precursor may be a solid precursor or a liquid precursor, and for example, molybdenum (Mo: molybdenum), boron (B: boron), phosphorus (P: phosphorous), copper (Cu: copper), gallium ( Ga: gallium), arsenic (As: arsenic), ruthenium (Ru: ruthenium), indium (In: indium), antimony (Sb: antimony), lanthanum (La: lanthanum), tantalum (Ta: tantalum), iridium (Ir) : iridium), decaborane (B10H14: decaborane), hafnium tetrachloride (HfCl4: zirconium tetrachloride), zirconium tetrachloride (ZrCl4: zirconium tetrachloride), indium trichloride (InCl3: indium trichloride), metal organic beta-diketonate complex β-diketonate complex), cyclopentadienyl cycloheptatrienyl titanium (CpTiChT: cyclopentadienyl cycloheptatrienyl titanium), aluminum trichloride (AlCl3: aluminum trichloride), titanium iodide (TixIy: titanium iodide), cyclooctatetraene cyclopentadienyl Titanium ((Cot)(Cp)Ti: cyclooctatetraene cyclopentadienyltitanium), bis(cyclopentadienyl)titanium diazide, tungsten carbonyl (Wx(CO)y: tungsten carbonyl), where x and y are natural numbers), bis(cyclopentadienyl)ruthenium(II) [Ru(Cp)2: bis(cyclopentadienyl)ruthenium (II)], ruthenium trichloride (RuCl3), and/or tungsten chloride (WxCly ) (where x and y are natural numbers). Those skilled in the art should know that the above-mentioned precursors are exemplary and the present invention is not limited only to such precursors.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

2 shows a canister 10 and a controller 200 in a vaporizer system according to an embodiment of the present invention. As shown in FIG. 1, the vaporizer system of the present invention includes a plurality of pipes connected to the canister 10, valves installed in each pipe, and a mass flow controller installed in the pipes to control the flow of fluid through the pipes ( MFC), a mass flow meter (MFM), and may further include components such as a heater for heating the canister 10, but in the drawings of this specification, these various pipes, valves, and devices in order not to obscure the gist of the present invention. Those skilled in the art will understand that .

In one embodiment, the canister 10 has a space for accommodating a precursor therein, an inlet 11 for supplying a fluid (eg, a carrier gas) into the canister 10, and a fluid (eg, vaporization) to the outside of the canister 10. / It may include an outlet 12 for discharging the sublimated precursor and carrier gas, etc.). In addition, the canister 10 includes a temperature sensor module 110 for measuring the temperature of a predetermined point in the interior space. Although one temperature sensor module 110 is shown in the embodiment shown in FIG. 2, it is of course possible to have one or more temperature sensor modules according to a specific embodiment of the invention.

In one embodiment, the temperature sensor module 110 includes two temperature sensors 111 and 112 spaced apart from each other up and down. Each of the temperature sensors 111 and 112 may be implemented as a known temperature sensor such as, for example, a thermocouple.

In one embodiment, one or more probes 100 for temperature measurement may be installed in order to install the temperature sensor module 110 in the inner space of the canister 10 . In the illustrated embodiment, the probe 100 includes a first probe 100a and a second probe 100b, and the first temperature sensor 111 and the second temperature sensor 112 are respectively connected to the first probe 100a. and the second probe 100b. In this way, when each of the temperature sensors 111 and 112 is installed in independent probes 100a and 100b, it is possible to prevent the temperature measurement values from being influenced by heat transfer between the temperature sensors. Therefore, if the temperature sensors 111 and 112 are designed to be thermally independent from each other, that is, to have no effect of temperature on each other, a single probe can be used as a matter of course.

For example, each of the probes 100a and 100b has an empty space therein and may be made of, for example, stainless steel. The wires of each of the temperature sensors 111 and 112 are connected upward through the inner space of each probe 100a and 100b to be connected to the controller 200, and accordingly, the measured value measured by each of the temperature sensors 111 and 112 is the controller ( 200) can be transmitted.

In the illustrated embodiment, each of the probes 100a and 100b is illustrated as being coupled to the upper case of the canister 10, but the installation position of each of the probes 100a and 100b may vary according to a specific embodiment. It will also be appreciated that in an alternative embodiment the temperature sensor module 110 may be installed on the inner sidewall of the canister 10, in which case a probe may not be required.

In one embodiment, the probe 100 for measuring temperature is coupled to and fixed to the canister 10 by a bonding method such as welding. Alternatively, the probe 100 may be fitted using known fitting methods such as, for example, VCR fitting (Vacuum Coupling Radiation fitting), VCO fitting (Vacuum Coupling O-ring fitting), UPG fitting (Universal Pipe Gasket fitting), and LOK fitting. It can be fastened to the canister 10 using one fitting connector according to .

The first temperature sensor 111 and the second temperature sensor 112 constituting the first temperature sensor module 110 are spaced apart from each other in the vertical direction. For example, in FIG. 2 , the second temperature sensor 112 is installed at a position vertically spaced apart from the first temperature sensor 111 by a predetermined distance (L), and therefore, the first temperature sensor 111 is inside the canister 10. , and the second temperature sensor 112 may measure the temperature of a second point spaced apart from the first point by a predetermined distance (L) inside the canister 10 .

The separation distance (L) between the first point and the second point may vary depending on specific embodiments, and may be, for example, several mm to several cm.

The controller 200 may estimate the level (surface or water level) of the precursor stored in the canister 10 based on the temperature measurement values received from the one or more temperature sensor modules 110 . The control unit 200 calculates a temperature difference value ΔT between the measured temperature of the first temperature sensor 111 of the temperature sensor module 110 and the measured temperature of the second temperature sensor 112 and calculates the difference value as a preset value. The level of the precursor can be estimated by comparing with the reference value, and the detailed operation of the control unit 200 will be described with reference to the drawings below.

3 is a diagram showing a state in which the precursor in the canister decreases in the first embodiment, and FIG. 4 is a diagram explaining the precursor level measurement method according to the first embodiment.

3 (a) shows that the first temperature sensor 111 of the temperature sensor module 110 and the second temperature sensor 112 located at a predetermined distance below it are all lower than the level (surface or water level) of the precursor. 3 (b) shows that as the precursor is consumed continuously (ie, the canister 10 is installed in the vaporizer system as shown in FIG. 1 and the precursor is sublimated and transported to the processing facility), the amount of the precursor gradually decreases This is a state in which the level of the precursor is lowered to the position of the first temperature sensor 111 . At this time, the precursor may be a liquid or a solid, but hereinafter, it is assumed to be a solid for convenience of explanation.

If the level of the precursor is higher than the first temperature sensor 111 as shown in FIG. 3 (a), both the first temperature sensor 111 and the second temperature sensor 112 are located inside the precursor and mutually Since it is within the adjacent separation distance, the measured temperature of the first temperature sensor 111 and the measured temperature of the second temperature sensor 112 will have the same or almost the same value (for example, the difference within the measurement error range of the temperature sensor), and thus the temperature difference The value ΔT is zero or has a value close to zero.

On the other hand, in the present invention, the "reference value" to be compared with the temperature difference value (ΔT) is less than or equal to the surface temperature drop value of the precursor due to sublimation of the precursor when the precursor is solid, and is measured between the first and second temperature sensors 111 and 112. It may be a larger value than the error. Also, when the precursor is a liquid, the reference value may be equal to or less than a temperature drop on the surface of the precursor due to vaporization of the precursor and greater than a measurement error between the first and second temperature sensors 111 and 112 .

Therefore, in the case of FIG. 3(a), the difference value ΔT between the measured temperature of the first temperature sensor 111 and the measured temperature of the second temperature sensor 112 will have a value smaller than the reference value. However, if the precursor level (surface) is reduced to the height L1 of the first temperature sensor 111 as shown in FIG. 3 (b) by consuming the precursor, in this case, since sublimation occurs on the surface of the precursor, the first temperature sensor Since the measured temperature of 111 is lower than the temperature measured by the second temperature sensor 112 by the temperature drop due to sublimation, the temperature difference value ΔT will be greater than or equal to the reference value.

Accordingly, the control unit 200 may compare the temperature difference value ΔT with the reference value and determine the level of the precursor based on the comparison result. For example, if the temperature difference value (ΔT) of the two temperature sensors is less than the reference value, it is determined that the level of the precursor is higher than that of the first temperature sensor 111, and if the temperature difference value (ΔT) is greater than the reference value, the level of the precursor is determined to be higher than the reference value. It can be determined that the level is equal to the height L1 of the first temperature sensor 111 .

On the other hand, in an alternative embodiment, instead of comparing the temperature difference value (ΔT) with a reference value, the level of the precursor may be determined according to a pre-prepared temperature difference value (ΔT)-precursor level correspondence table. This correspondence table may match and store precursor level values corresponding to the temperature difference values ΔT between the first and second points in advance. For example, in the correspondence table, if the temperature difference value (ΔT) is 0 or a value within the error range of the temperature sensor, the precursor level corresponds to “exceeding the T1 height”, the precursor is a solid, and the surface temperature drop of the precursor due to sublimation of the precursor Assuming that the value is, for example, 1 degree Celsius, the precursor level may correspond to "the height of T1" in the correspondence table for the temperature difference value ΔT of 1 degree or more.

Therefore, in this embodiment, the control unit 200 may output a precursor level corresponding to the difference value ΔT by referring to the correspondence table without comparing the temperature difference value ΔT with the reference value.

Figure 4 shows an exemplary method of measuring the level of the precursor in the controller 200 according to the above configuration. Referring to FIG. 4 , in step S110, the first temperature sensor 111 and the second temperature sensor 112 respectively measure temperatures. After that, the controller 200 calculates the temperature difference value ΔT between the two temperature sensors (S120), and outputs the level of the precursor based on the calculation result (S130). For example, if the temperature difference value ΔT is smaller than the reference value, it is determined that the level of the precursor is higher than the first temperature sensor 111 as shown in FIG. 3 (a), and if the temperature difference value ΔT is greater than the reference value It can be determined that the level of the precursor has decreased to the height L1 of the first temperature sensor 111 as shown in FIG. 3(b). Alternatively, in an alternative embodiment, a precursor level corresponding to the calculated difference value (ΔT) may be output by referring to a pre-stored difference value (ΔT)-precursor level correspondence table.

And, in one embodiment, when it is determined that the precursor level has decreased to the height L1 of the first temperature sensor 111, a step of notifying a manager of the precursor level may be further included (S140).

5 is a diagram showing a state in which the precursor in the canister decreases in the second embodiment, and FIG. 6 is a diagram explaining a precursor level measurement method according to the second embodiment.

Referring to FIG. 5, the temperature sensor module 110 in FIG. 5 (a) includes a first temperature sensor 111 and a second temperature sensor 112 spaced apart from each other by a predetermined distance below the first temperature sensor 111, and the level of the precursor is It is located between the first temperature sensor 111 and the second temperature sensor 112, and FIG. 5 (b) shows a state in which the level of the precursor goes down to the position of the second temperature sensor 112 as the precursor is continuously consumed. to be.

If the level of the precursor is between the first temperature sensor 111 and the second temperature sensor 112 as shown in FIG. 5 (a), the first temperature sensor 111 is located outside the precursor and the second temperature sensor 112 is located inside the precursor, and since the temperature outside the precursor is generally higher than the temperature inside the precursor in the inner space of the canister 10, the measured temperature of the first temperature sensor 111 and the second temperature sensor 112 The temperature difference value ΔT between the measured temperatures of ) has a predetermined value greater than zero. At this time, the specific value of the temperature difference value ΔT may vary depending on the specific configuration or operating state of the vaporizer system, such as the type of precursor or the heating temperature of the canister 10 .

In addition, in this embodiment, the "reference value" to be compared with the temperature difference value (ΔT) is greater than [temperature difference between the inside and outside of the precursor in the canister] and [between the inside and outside of the precursor in the canister] when the precursor is solid. It may be set to have a value smaller than the sum of [temperature difference of the precursor] and [temperature drop value of the precursor surface due to sublimation of the precursor]. If the precursor is a liquid, the reference value is greater than [temperature difference between the inside and outside of the precursor in the canister] and [temperature difference between the inside and outside of the precursor in the canister] and [temperature drop on the surface of the precursor due to vaporization of the precursor]. value] may be set to have a value smaller than the sum of

Therefore, in the state of FIG. 5 (a), it can be seen that the temperature difference value ΔT between the measured temperature of the first temperature sensor 111 and the measured temperature of the second temperature sensor 112 has a value smaller than the reference value. And, when the precursor is consumed and the precursor level decreases to the height L2 of the second temperature sensor 112 as shown in FIG. 5 (b), in this case, since sublimation occurs on the surface of the precursor, the temperature difference value ΔT will be greater than or equal to the reference value.

Accordingly, the control unit 200 may compare the temperature difference value ΔT with the reference value and determine the level of the precursor based on the comparison result. For example, if the temperature difference value (ΔT) of the two temperature sensors is less than the reference value, it is determined that the level of the precursor is located between the first temperature sensor 111 and the second temperature sensor 112 as shown in FIG. 5 (a). And, if the temperature difference value ΔT is equal to or greater than the reference value, it can be determined that the level of the precursor is equal to the height L2 of the second temperature sensor 112 .

Meanwhile, similar to the above-described first embodiment, the level of the precursor may be determined using the temperature difference value (ΔT)-precursor level correspondence table prepared in advance in the second embodiment of FIGS. 5 and 6. This correspondence table stores precursor level values corresponding to the temperature difference values ΔT between the first point and the second point by matching them in advance, and the control unit 200 determines the calculated difference value ΔT based on the correspondence table. A corresponding precursor level can be output.

Figure 6 shows an exemplary method of measuring the level of the precursor in the controller 200 according to the above configuration. Referring to FIG. 6 , in step S210, the first temperature sensor 111 and the second temperature sensor 112 respectively measure temperatures. After that, the control unit 200 calculates the temperature difference value ΔT between the two temperature sensors (S220), and outputs the level of the precursor based on the calculation result (S230). For example, if the temperature difference value ΔT is smaller than the reference value, it is determined that the level of the precursor is between the first temperature sensor 111 and the second temperature sensor 112 as shown in FIG. 5 (a), and the temperature difference value ( If ΔT) is equal to or greater than the reference value, it can be determined that the level of the precursor has decreased to the height L2 of the second temperature sensor 112 as shown in FIG. 5(b). Alternatively, in an alternative embodiment, a precursor level corresponding to the calculated difference value (ΔT) may be output by referring to a pre-stored difference value (ΔT)-precursor level correspondence table.

And, in one embodiment, when it is determined that the precursor level has decreased to the height L2 of the second temperature sensor 112, a step of notifying a manager of the precursor level may be further included (S240).

Fig. 7 shows a state in which the precursor in the canister decreases in the third embodiment.

The third embodiment is a case in which the first embodiment of FIG. 3 and the second embodiment of FIG. 5 are combined. Referring to FIG. 7, the temperature sensor module 110 includes a first temperature sensor 111 and a second temperature sensor 112 spaced apart from each other by a predetermined distance below the first temperature sensor 111, and FIG. 7 (a) shows the level of the precursor. It is a state above the two temperature sensors 111 and 112, and it is shown that the precursor level gradually decreases from FIG. 7(b) to FIG. 7(e). That is, in FIG. 7 (b), the precursor level is at the height of the first temperature sensor 111, and in FIG. 7 (c), the precursor level is between the first temperature sensor 111 and the second temperature sensor 112. state, FIG. 7(d) shows a state where the precursor level is at the height of the second temperature sensor 112, and FIG. 7(e) shows a state where the precursor level is lowered to a position lower than the second temperature sensor 112, respectively. .

Therefore, in the case of FIG. 7 (a), the temperature difference value ΔT between the measured temperature of the first temperature sensor 111 and the measured temperature of the second temperature sensor 112 has a value smaller than the first reference value, and the precursor is When the precursor level decreases to the height L1 of the first temperature sensor 111 as shown in FIG. 7(b), the temperature difference value ΔT is equal to the first reference value or will be big

In this case, the "first reference value" may be less than or equal to a surface temperature drop of the precursor due to sublimation when the precursor is solid and greater than a measurement error between the first and second temperature sensors 111 and 112. Also, when the precursor is a liquid, the first reference value may be less than or equal to a temperature drop on the surface of the precursor due to vaporization of the precursor and greater than a measurement error between the first and second temperature sensors 111 and 112 .

When the level of the precursor decreases to between the first temperature sensor 111 and the second temperature sensor 112, as shown in FIG. 7 (c), the measured temperature of the first temperature sensor 111 and the first temperature sensor 112 The temperature difference value (ΔT) between the measured temperatures of has a value smaller than the second reference value, and the precursor level is reduced to the height (L2) of the second temperature sensor 112 as shown in FIG. 7 (d) because more precursors are consumed. If so, the temperature difference value ΔT will be equal to or greater than the second reference value due to sublimation on the surface of the precursor.

When the precursor is a solid, the "second reference value" is greater than [temperature difference between the inside and outside of the precursor in the canister] and [temperature difference between the inside and outside of the precursor in the canister] and [precursor by sublimation of the precursor]. If the precursor is a liquid, the second reference value is greater than the [temperature difference between the inside and outside of the precursor in the canister] and [the inside of the precursor in the canister]. It may be set to a value smaller than the sum of [temperature difference between and outside] and [temperature drop on the surface of the precursor due to vaporization of the precursor].

8 shows an exemplary method of measuring the precursor level in the controller 200 according to the above configuration. Referring to FIG. 8 , in step S310, the first temperature sensor 111 and the second temperature sensor 112 respectively measure temperatures. After that, the control unit 200 calculates the temperature difference value ΔT between the two temperature sensors (S320), and outputs the level of the precursor based on the calculation result (S330).

For example, in step S330, the control unit 200 may compare the calculated temperature difference value ΔT with a first reference value to determine the level of the precursor. At this time, the first reference value is the level described with reference to FIG. That is, when the precursor is a solid, it may be less than or equal to the surface temperature drop value of the precursor due to sublimation of the precursor and may be greater than the measurement error between the first and second temperature sensors 111 and 112, and when the precursor is a liquid, the first reference value is It may be equal to or less than the temperature drop on the surface of the precursor due to vaporization of the precursor and greater than the measurement error between the first and second temperature sensors 111 and 112.

Therefore, in step S330, when the temperature difference value ΔT is smaller than the first reference value, it is determined that the level of the precursor is higher than the first temperature sensor 111 as shown in FIG. 7 (a), and the temperature difference value ( If ΔT) is equal to or greater than the first reference value, it can be determined that the level of the precursor has decreased to the height L1 of the first temperature sensor 111 as shown in FIG. 7(b). Alternatively, in an alternative embodiment of step S330, the control unit 200 refers to a pre-stored difference value ΔT-precursor level correspondence table, and the precursor level corresponding to the difference value ΔT calculated in step S320. can also be output.

After that, as the precursor is consumed more, the precursor level is positioned between the first temperature sensor 111 and the second temperature sensor 112 as shown in FIG. The temperature of the second temperature sensor 112 may be measured (S340), a temperature difference value (ΔT) of the measured temperature may be calculated (S350), and the level of the precursor may be output based on the calculation result. (S360).

For example, in step S360, the control unit 200 may determine the level of the precursor by comparing the calculated temperature difference value ΔT with a second reference value. In the case where the precursor is solid, it is greater than [temperature difference between the inside and outside of the precursor in the canister] [temperature difference between the inside and outside of the precursor in the canister] and [temperature drop on the surface of the precursor due to sublimation of the precursor] may be set to a value smaller than the sum of , and if the precursor is a liquid, the second reference value is greater than [temperature difference between the inside and outside of the precursor in the canister] and [temperature difference between the inside and outside of the precursor in the canister] It may be set to a value smaller than the sum of [the temperature drop value of the precursor surface due to vaporization of the precursor].

Therefore, in step S360, if the temperature difference value ΔT is smaller than the second reference value, it is assumed that the level of the precursor is located between the first temperature sensor 111 and the second temperature sensor 112 as shown in FIG. 7(c). And, if the temperature difference value ΔT is greater than or equal to the second reference value, it can be determined that the level of the precursor has decreased to the height L2 of the second temperature sensor 112 as shown in FIG. 7(d). Alternatively, in an alternative embodiment of step S360, the controller 200 may refer to a pre-stored difference value (ΔT)-precursor level correspondence table to output a precursor level corresponding to the calculated difference value (ΔT).

And in one embodiment, the precursor level is reduced to the height L2 of the second temperature sensor 112 as in the state of FIG. 7 (d) or the height of the second temperature sensor 112 as in the state of FIG. 7 (e) ( If it is determined that the level of the precursor has decreased to less than L2), a step (S360) of notifying the manager of the level of the precursor may be further included.

As described above, those skilled in the art to which the present invention pertains can understand that various modifications and variations are possible from the description of this specification. Therefore, the scope of the present invention should not be limited to the described embodiments and should not be defined, but should be defined by not only the claims to be described later, but also those equivalent to these claims.

10: canister
100: probe for temperature measurement
110: temperature sensor module
111,112: temperature sensor
200: control unit

Claims (9)

As a vaporizer system,
a canister capable of storing the precursor;
a heater thermally coupled to the canister to vaporize the precursor;
a first temperature sensor measuring a temperature of a first point inside the canister;
a second temperature sensor measuring a temperature of a second point spaced downward by a predetermined distance from the first point; and
A controller for calculating the level of the precursor based on the measured temperatures of the first and second temperature sensors; includes,
The control unit calculates a difference value (ΔT) between the measured temperatures of the first point and the second point, and determines that the surface of the precursor is at the height of the first point when the difference value (ΔT) is equal to or greater than a predetermined first reference value. And configured to output the level of the precursor stored in the canister,
The first reference value is a vaporizer system, characterized in that a value smaller than the temperature drop value of the precursor surface due to sublimation of the precursor when the precursor is a solid. According to claim 1,
an outlet for supplying the precursor inside the canister to the outside; and
The vaporizer system further comprising an on-off valve installed at the outlet. According to claim 1,
The first temperature sensor and the second temperature sensor are installed in the first probe and the second probe, respectively,
The vaporizer system, characterized in that each of the first and second probes are integrally coupled and attached to the inner surface of the canister. According to claim 1,
The vaporizer system, characterized in that the first and second probes are integrally coupled and attached to the canister using at least one fitting connector among VCR, VCO, UPG, and LOK fittings. delete delete According to claim 1
The control unit determines that the surface of the precursor is at the height of the second point when the calculated difference value (ΔT) is equal to or greater than a predetermined second reference value. According to claim 7,
The second reference value is greater than [temperature difference between the inside and outside of the precursor in the canister] when the precursor is solid, and [temperature difference between the inside and outside of the precursor in the canister] and [the temperature difference between the inside and outside of the precursor in the canister]. Vaporizer system, characterized in that the value is smaller than the sum of the temperature drop value of the precursor surface due to sublimation. According to claim 1,
Characterized in that the control unit outputs a precursor level corresponding to the calculated difference value (ΔT) based on a correspondence table in which precursor level values corresponding to the temperature difference value (ΔT) of the first point and the second point are matched carburetor system.

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