KR102641706B1 - Apparatus for purging wafer using heated nitrogen - Google Patents

Abstract

In the present invention, a supply line is provided to supply nitrogen to the inside of the wafer receiving device, an exhaust line is provided to exhaust nitrogen from the wafer receiving device, and nitrogen is supplied to the inside of the wafer receiving device by a heating unit installed in the supply line. Heating nitrogen is used to heat nitrogen to produce nitrogen, and the wafer purge controller receives the humidity measurement value of nitrogen and adjusts the humidity inside the wafer receiving device by controlling the supply valve installed in the supply line and the heating unit. It relates to a wafer purge device using.
According to the present invention, efficient nitrogen purging of wafers can be achieved, and it can be easily applied to devices for storing, storing or transporting wafers, and humidity control of wafers through purging of heated nitrogen can be achieved. By making this possible, it has the effect of preventing defects in semiconductor devices due to humidity.

Description

Wafer purging device using heated nitrogen {Apparatus for purging wafer using heated nitrogen}

The present invention relates to a wafer purge device using heated nitrogen, and more specifically, to enable efficient nitrogen purge of the wafer and to control the humidity of the wafer through purging of heated nitrogen, thereby enabling semiconductor It relates to a wafer purge device using heated nitrogen to prevent defects in devices.

Generally. To manufacture semiconductor devices, wafers go through various unit processes, including an oxidation process, photo process, etching process, deposition process, ion implantation process, and wiring process.

In order to perform this unit process, the wafer is repeatedly transferred and returned to the processing equipment.

If wafers are loaded or stored with the process gas used during the processing process remaining on the surface, precision processing becomes difficult and secondary contamination occurs, which makes it difficult to manufacture high-quality semiconductor devices.

In order to solve this problem, the wafer goes through a process of purging with nitrogen. As a related conventional technology, "Wafer purge device for buffer chamber" in Korean Patent Publication No. 10-2019-0122040 has been proposed. A chamber portion having an entrance and exit for substrates to enter and exit, and a loading space in which a plurality of substrates are loaded. A purge gas is sprayed between a body formed along the loading direction of the substrate, a gas passage inside the body, and a plurality of substrates branched from the gas passage and disposed along the loading direction and loaded in the loading space. A gas injection unit including a gas injection port; It includes a gas intake unit that intakes the purge gas and contaminants in the loading space and exhausts them to the outside of the chamber unit.

Meanwhile, for wafers, humidity is an important factor after processing. In particular, as semiconductor devices become more advanced, humidity has a significant impact on causing defects in the production of high-quality products. For this reason, it is important to control humidity, which affects the occurrence of defects in semiconductor devices. Since it is not easy to control the entire humidity of the semiconductor FAB, there was a need to control the humidity even in the space where the wafer is accommodated.

However, this prior art only uses nitrogen for purging and does not include any structure for controlling humidity related to defects in semiconductor devices, so there is a need for improvement.

In order to solve the problems of the prior art as described above, the present invention provides efficient nitrogen purge for wafers, can be easily applied to devices for storing, storing, or transporting wafers, and purges heated nitrogen. The purpose is to prevent defects in semiconductor devices due to humidity by enabling humidity control on the wafer.

Other objects of the present invention may be easily understood through the description of the examples below.

In order to achieve the above object, according to one aspect of the present invention, a supply line is provided to supply nitrogen to the inside of the wafer receiving device, an exhaust line is provided to exhaust nitrogen from the wafer receiving device, and the supply Nitrogen to be supplied into the wafer receiving device is heated by a heating unit installed in the line, and the wafer purge controller receives the humidity measurement value of nitrogen and controls the supply valve installed in the supply line and the heating unit. A wafer purge device using heated nitrogen is provided to control humidity inside the wafer receiving device.

a temperature and humidity sensor that measures the temperature and humidity of either or both nitrogen supplied into the wafer receiving device and nitrogen exhausted from the wafer receiving device and provides the measured values to the wafer purge controller; And a wafer detection sensor that detects the loading and unloading of the wafer inside the wafer receiving device and provides a detection signal to the wafer purge controller, wherein the wafer purge controller receives a detection signal from the wafer detection sensor. Upon reception, control of the supply valve for supplying nitrogen to the wafer is performed, and after a set time has elapsed, the humidity measurement value measured by the temperature and humidity sensor is compared with the upper limit setting value, and the humidity measurement value is the upper limit setting value. If exceeds, control to output an alarm through the alarm generator, if the humidity measured value is less than the upper limit set value, compare the humidity measured value and the lower limit set value, and if the humidity measured value is less than the lower limit set value, Controlling the supply valve to stop the supply of nitrogen to the wafer, and controlling the supply valve to maintain the supply of nitrogen to the wafer if the humidity measurement value is more than the lower limit set value, The process of supplying nitrogen to the wafer and stopping supply of nitrogen to the wafer through the humidity measurement is repeated until the detection signal from the wafer detection sensor is not received, the upper limit setting value is 8 to 12% RH, and the lower limit is The set value may be 2 to 5% RH.

The heating unit includes a heating line connected at both ends to the supply line to provide a bypass path; A heater installed in the heating line to heat nitrogen passing through; First and second supply valves respectively installed at both ends of the heating line and opening and closing the supply of nitrogen; and an inlet temperature and humidity sensor and an outlet temperature and humidity sensor, which are respectively installed at the front and rear ends of the heater in the heating line and provide measured values of temperature and humidity as information to the wafer purge controller.

The supply line and the exhaust line are each equipped with a supply flow switch and an exhaust flow switch, and the exhaust line has a differential pressure sensor installed to measure the pressure difference between the front and rear ends of the exhaust flow switch and the wafer purge controller. can provide pressure measurements.

A supply control valve installed at a rear end of the supply valve in the supply line; A bypass line connected from the supply line to bypass the supply control valve; A flow control needle valve installed in the bypass line; a cleaning line connected from between the supply valve and the supply control valve in the supply line to a front end of the exhaust flow switch in the exhaust line; And a cleaning valve installed to open and close the supply of nitrogen from the cleaning line to the exhaust line, wherein the wafer purge controller detects the wafer inside the wafer receiving device through a wafer detection sensor, The supply control valve is operated until a set amount of nitrogen is supplied, and then the supply control valve is blocked. Then, nitrogen is supplied to the wafer inside the wafer receiving device by the flow control needle valve, and the wafer is detected. When it is determined through a sensor that the wafer is unloaded from the wafer receiving device, nitrogen is supplied to the exhaust flow switch and the differential pressure sensor through the cleaning line by opening the cleaning valve for a predetermined period of time to perform cleaning. You can do it.

According to the wafer purge device using heated nitrogen according to the present invention, efficient nitrogen purge of the wafer can be achieved, and it can be easily applied to devices for storing, storing, or transporting wafers, and can be used to purge wafers with heated nitrogen. By making it possible to control the humidity of the wafer through purging, it has the effect of preventing defects in semiconductor devices due to humidity.

Figure 1 is a configuration diagram showing a wafer purge device using heated nitrogen according to an embodiment of the present invention.
Figure 2 is a configuration diagram for controlling a wafer purge device using heated nitrogen according to an embodiment of the present invention.
Figure 3 is a flowchart showing a humidity control process in a wafer purge device using heated nitrogen according to an embodiment of the present invention.

Since the present invention can be subject to various changes and can have various embodiments, specific embodiments will be illustrated in the drawings and described in detail. However, this is not intended to limit the present invention to specific embodiments, but should be understood to include all changes, equivalents, and substitutes included in the technical idea and scope of the present invention, and may be modified into various other forms. The scope of the present invention is not limited to the following examples.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the attached drawings, and identical or corresponding components will be assigned the same reference numerals regardless of reference numerals, and redundant description thereof will be omitted.

Figure 1 is a configuration diagram showing a wafer purge device using heated nitrogen according to an embodiment of the present invention, and Figure 2 is a configuration diagram for controlling the wafer purge device using heated nitrogen according to an embodiment of the present invention. .

Referring to Figures 1 and 2, the wafer purge device 100 using heated nitrogen according to an embodiment of the present invention is provided with a supply line 120 to supply nitrogen to the inside of the wafer receiving device 10, and the wafer An exhaust line 130 is provided to exhaust nitrogen from the receiving device 10, and the nitrogen to be supplied into the wafer receiving device 10 is heated by the heating unit 180 installed in the supply line 120. , the wafer purge controller 190 receives the nitrogen humidity measurement value and controls the humidity inside the wafer receiving device 10 by controlling the supply valve 121 and the heating unit 180 installed in the supply line 120. To this end, it may include a supply line 120, an exhaust line 130, temperature and humidity sensors 141 and 142, a heating unit 180, and a wafer purge controller 190.

Meanwhile, the wafer receiving device 10 includes, for example, a process chamber, buffer chamber, transfer chamber, storage device, transfer device, and other various devices that accommodate wafers in the inner receiving space 11 for storage, waiting, or transfer. may apply. In this wafer receiving device 10, the wafers 20 may be loaded directly inside as a single wafer or multiple wafers, or may be loaded inside together with a wafer storage device such as a wafer cassette. In addition, the wafer receiving device 10 has an inlet 12 and an exhaust port 13 for connection with the supply port provided at the end of the supply line 120 and the exhaust port provided at the end of the exhaust line 130. It can be provided. Therefore, the wafer receiving device 10 ensures that nitrogen supplied through the supply line 120 is supplied to the inside through the inlet 12, and nitrogen inside is supplied to the exhaust line 130 through the exhaust port 13. It can be made to exhaust.

The supply line 120 is connected to supply nitrogen to the inlet 12 of the wafer receiving device 10, and a supply valve 121 for opening and closing the supply of nitrogen and a filter 122 for filtering nitrogen are installed. . The supply valve 121 may be made of a control valve, similar to the valve controlled by the wafer purge controller 190 below, and may be made of a solenoid valve, for example. The filter 122 may be composed of a single or multiple filtering members made of various materials and structures to filter and remove foreign substances such as particles contained in passing nitrogen.

The supply line 120 may be equipped with a supply flow switch 124, which allows monitoring of the nitrogen supply amount. The supply flow switch 124 may be installed singly or in multiple configurations on the supply line 120, as needed. The supply flow switch 124 can set a flow rate of 2 to 100 L/min, for example.

The exhaust line 130 is connected to the exhaust port 13 of the wafer receiving device 10 to exhaust nitrogen. The exhaust line 130 may be equipped with an exhaust flow switch 132, which allows monitoring of the nitrogen exhaust amount.

A supply blocking valve 123 and an exhaust blocking valve 131 to block the movement of nitrogen may be installed in the supply line 120 and the exhaust line 130, respectively. The supply blocking valve 123 and the exhaust blocking valve (131) may be made of a manual valve to enable manual operation, but is not necessarily limited thereto, and may be made of a valve operated by an operation signal.

The exhaust line 130 allows the differential pressure sensor 170, which is installed to measure the pressure difference between the front and rear ends of the exhaust flow switch 132, to provide pressure measurement values to the wafer purge controller 190. Therefore, the wafer purge controller 190 detects the accumulation of fume in the exhaust flow switch 132 from the measured value of the differential pressure sensor 170, and upon detecting this, provides an alarm to a designated terminal, generates an alarm sound, or sends an alarm, etc. An alarm such as lighting can be generated, and through this, the filtration level of the exhaust flow switch 132 can be managed or the replacement time can be identified.

The heating unit 180 is installed to heat nitrogen supplied to the supply line 120. The heating unit 180 includes a heating line 181 that is connected at both ends to the supply line 120 to provide a bypass path, a heater 182 installed in the heating line 181 to heat nitrogen passing through, and a heater 182 that heats nitrogen passing through the heating line 181. It can be installed at both ends of the line 181, respectively, and is installed at the front and rear ends of the first and second supply valves 183 and 184 for opening and closing the supply of nitrogen, and the heater 182 in the heating line 181, It may include an inlet temperature and humidity sensor 185 and an outlet temperature and humidity sensor 186 that provide measured values of temperature and humidity as information to the wafer purge controller 190. Here, the heater 182 is not limited to a heating wire that converts electrical energy into thermal energy, and various heating devices, including a heat exchanger that provides heat to nitrogen through heat exchange with a heat medium, may be used. Each of the first and second supply valves 183 and 184 may be configured as a three-way valve or a plurality of two-way valves to switch or block the flow of nitrogen to the supply line 120 or the heating line 181. The inlet temperature and humidity sensor 185 and the outlet temperature and humidity sensor 186 provide the temperature and humidity of nitrogen to control the nitrogen to be heated to have the desired temperature and humidity. Either one of these measured values is used or , the average value, minimum value, or maximum value can be used. This heating unit 180 adjusts the temperature of nitrogen supplied to the wafer 20 in the wafer receiving device 10 under the control of the wafer purge controller 190, so that the temperature and humidity of nitrogen are required for the wafer 20. Optimal temperature and humidity conditions can be achieved.

The wafer purge device 100 using heated nitrogen according to an embodiment of the present invention has a temperature of one or both of the nitrogen supplied to the inside of the wafer receiving device 10 and the nitrogen exhausted from the wafer receiving device 10. and temperature and humidity sensors 141 and 142 that measure humidity and provide the measured value to the wafer purge controller 190, and a wafer detection sensor installed to detect loading and unloading of the wafer 20 inside the wafer receiving device 10. (151,152) may be further included.

The temperature and humidity sensors 141 and 142 are installed to measure the temperature and humidity of one or both of the nitrogen supplied to the wafer receiving device 10 and the nitrogen exhausted from the wafer receiving device 10. For example, as in this embodiment, It may be composed of a supply temperature and humidity sensor 141 installed near the wafer receiving device 10 in the supply line 120, and an exhaust temperature and humidity sensor 142 installed near the wafer receiving device 10 in the exhaust line 130. As a standard for temperature and humidity control by the wafer purge controller 190, the average value of the temperature or humidity measured by them is used, any one of the temperature or humidity measured by them is used, or the maximum or minimum value is used. It can be configured to do so.

The wafer detection sensors 151 and 152 are installed to detect the wafer 20 accommodated in the receiving space 11 of the wafer receiving device 10 and provide a detection signal to the wafer purge controller 190, for example, receiving space ( 11), it may be composed of a first wafer detection sensor 151 and a second wafer detection sensor 152 installed on both sides, respectively. The wafer purge controller 190 determines that the wafer 20 is loaded in the receiving space 11 when receiving a detection signal from either or both of the first and second wafer detection sensors 151 and 152, or 2 Using the detection signals of all of the wafer detection sensors 151 and 152, it can be determined that the wafer 20 is loaded into the receiving space 11 according to the set order in which the detection signals are received, and through this, the wafer 20 is loaded into the receiving space 11. It can be determined whether a purge operation should be performed or whether it should be stopped.

The wafer purge controller 190 receives measured values from the temperature and humidity sensors 141 and 142 and controls the operation of the supply valve 121 and the heating unit 180. Referring to FIG. 3, for example, when receiving detection signals from the wafer detection sensors 151 and 152 (S11), the wafer purge controller 190 controls the supply valve 121 for supplying nitrogen to the wafer 20. (S12), and after a set time, for example, 1 to 60 minutes (S13), the humidity measurement value measured by the temperature and humidity sensor (141, 142) and the upper limit setting value can be compared (S14, S15), and the humidity measurement value is If the upper limit setting value is exceeded, an alarm can be controlled to be output through the alarm generator (not shown) (S16). If the humidity measurement value is below the upper limit setting value, the humidity measurement value and the lower limit setting value can be compared (S17). ), if the humidity measurement value is less than the lower limit setting value, control of the supply valve 121 can be performed to stop the nitrogen supply to the wafer 20, and if the humidity measurement value is more than the lower limit setting value, the wafer 20 ) can control the supply valve 121 to maintain the supply of nitrogen (S19), and control the wafer 20 through humidity measurement until the detection signal from the wafer detection sensors 151 and 152 is not received. The nitrogen supply and nitrogen supply stop processes (S14 to S19) can be repeated. Here, the upper limit setting value may be 8 to 12% RH, for example, 10% RH. The lower limit setting may be 2 to 5% RH, for example 3.5% RH. In addition, these upper limit set values and lower limit set values can be appropriately changed by manipulating the control panel (not shown), and the wafer purge controller 190, which has received the changed upper limit set values and lower limit set values by the control unit, sets the changed upper limit set values. Control is performed using the upper and lower limit settings. Therefore, through comparison with the two-stage setting value range based on the upper limit setting value and the lower limit setting value, efficient humidity control for the wafer 20 is possible and defects in semiconductor devices due to moisture are greatly reduced. can do.

The wafer purge controller 190 manages the internal humidity of the wafer 20 within, for example, 10% RH and the internal temperature within a set temperature range through real-time measurement and monitoring of temperature and humidity through the temperature and humidity sensors 141 and 142. , it can contribute to improving productivity and quality for the manufacture of semiconductor devices by preventing the generation of natural oxides and contamination. In addition, the wafer purge controller 190 receives detection signals from the wafer detection sensors 151 and 152, allowing it to determine the start and stop of the purge operation.

The wafer purge device 100 using heated nitrogen according to an embodiment of the present invention includes a supply control valve 126 installed at the rear of the supply valve 121 in the supply line 120, and a supply control valve 126 installed in the supply line 120. A bypass line 127 connected to bypass the control valve 126, a flow control needle valve 128 installed on the bypass line 127, and a supply valve 121 and supply from the supply line 120. To open and close the cleaning line 133 connected to the front end of the exhaust flow switch 132 in the exhaust line 130 between the control valve 126 and the supply of nitrogen from the cleaning line 133 to the exhaust line 130. It may further include an installed cleaning valve 134, and the wafer purge controller 190 operates a supply control valve ( 126) is operated until the set amount of nitrogen is supplied, and then the supply control valve 126 is blocked. Then, nitrogen is supplied to the wafer 20 inside the wafer receiving device 10 by the flow control needle valve 128. When it is determined that the wafer 20 is unloaded from the wafer receiving device 10 through the wafer detection sensors 151 and 152, the cleaning valve 134 is activated for a set time, for example 3 to 10 seconds, for example 5 seconds. ) is opened, nitrogen can be supplied to the exhaust flow switch 132 and the differential pressure sensor 170 through the cleaning line 133 to perform cleaning.

According to the wafer purge device using heated nitrogen according to the present invention, efficient nitrogen purge of the wafer can be achieved, and it can be easily applied to devices for storing, storing, or transporting wafers.

In addition, according to the present invention, it is possible to control the humidity of the wafer through purging of heated nitrogen, thereby preventing defects in the semiconductor device due to humidity.

Although the present invention has been described with reference to the accompanying drawings, it goes without saying that various modifications and variations can be made without departing from the technical spirit of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined by the claims described below as well as equivalents to these claims.

10: wafer receiving device 11: receiving space
12: Inlet 13: Exhaust port
20: wafer 120: supply line
121: supply valve 122: filter
123: Supply blocking valve 124: Supply flow switch
126: Supply control valve 127: Bypass line
128: Flow control needle valve 130: Exhaust line
131: exhaust blocking valve 132: exhaust flow switch
133: Cleaning line 134: Cleaning valve-
141: Supply temperature and humidity sensor 142: Exhaust temperature and humidity sensor
151: first wafer detection sensor 152: second wafer detection sensor
170: differential pressure sensor 180: heating unit
181: heating line 182: heater
183: first supply valve 184: second supply valve
185: Inlet temperature and humidity sensor 186: Outlet temperature and humidity sensor
190: Wafer purge controller

Claims (5)

A supply line is provided to supply nitrogen to the inside of the wafer receiving device, an exhaust line is provided to exhaust nitrogen from the wafer receiving device, and nitrogen is supplied to the inside of the wafer receiving device by a heating unit installed in the supply line. is heated, and the wafer purge controller receives the humidity measurement value of nitrogen and controls the humidity inside the wafer receiving device by controlling the supply valve installed in the supply line and the heating unit,
The supply line and the exhaust line are,
A supply flow switch and an exhaust flow switch are installed respectively,
The exhaust line is,
A differential pressure sensor installed to measure the pressure difference between the front and rear ends of the exhaust flow switch provides a pressure measurement value to the wafer purge controller,
A supply control valve installed at a rear end of the supply valve in the supply line;
A bypass line connected from the supply line to bypass the supply control valve;
A flow control needle valve installed in the bypass line;
a cleaning line connected from between the supply valve and the supply control valve in the supply line to a front end of the exhaust flow switch in the exhaust line; and
It further includes a cleaning valve installed to open and close the supply of nitrogen from the cleaning line to the exhaust line,
The wafer purge controller,
When the wafer is detected inside the wafer receiving device through the wafer detection sensor, the supply control valve is operated until a set amount of nitrogen is supplied, and then when the supply control valve is blocked, the flow control needle valve is operated. nitrogen is supplied to the wafer inside the wafer receiving device, and when it is determined through the wafer detection sensor that the wafer is unloaded from the wafer receiving device, the cleaning line is opened by opening the cleaning valve for a predetermined period of time. A wafer purge device using heated nitrogen, characterized in that nitrogen is supplied to the exhaust flow switch and the differential pressure sensor through to perform cleaning. In claim 1,
a temperature and humidity sensor that measures the temperature and humidity of either or both nitrogen supplied into the wafer receiving device and nitrogen exhausted from the wafer receiving device and provides the measured values to the wafer purge controller; and
It further includes a wafer detection sensor that detects loading and unloading of wafers into the wafer receiving device and provides a detection signal to the wafer purge controller,
The wafer purge controller,
Upon receiving the detection signal from the wafer detection sensor, control of the supply valve for supplying nitrogen to the wafer is performed, and after a set time has elapsed, the humidity measurement value measured by the temperature and humidity sensor is compared with the upper limit setting value, If the humidity measurement value exceeds the upper limit setting value, an alarm is output through the alarm generator. If the humidity measurement value is less than the upper limit setting value, the humidity measurement value is compared with the lower limit setting value, and the humidity measurement value is controlled to output an alarm through the alarm generator. If the humidity measurement value is less than the lower limit set value, control of the supply valve is performed to stop the supply of nitrogen to the wafer, and if the humidity measurement value is greater than the lower limit set value, the supply valve is controlled to maintain the supply of nitrogen to the wafer. Control the supply valve and repeat the process of supplying nitrogen to the wafer through the humidity measurement and stopping the nitrogen supply until the detection signal from the wafer detection sensor is not received,
The upper limit setting value is,
8 to 12% RH;
The lower limit setting value is,
Wafer purge device using heated nitrogen, 2 to 5% RH. In claim 1,
The heating unit,
A heating line connected at both ends to the supply line to provide a bypass path;
A heater installed in the heating line to heat nitrogen passing through;
First and second supply valves respectively installed at both ends of the heating line and opening and closing the supply of nitrogen; and
An inlet temperature and humidity sensor and an outlet temperature and humidity sensor that are respectively installed at the front and rear ends of the heater in the heating line and provide measured values of temperature and humidity as information to the wafer purge controller;
A wafer purge device using heated nitrogen, including a.
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