KR102403088B1 - Apparatus and Method of Processing wafer - Google Patents

Abstract

It relates to a substrate processing apparatus and method. The substrate processing method according to the present embodiment is a method of exhausting a source gas inside a process chamber for depositing a thin film on a substrate. First, a main exhaust valve connecting the process chamber exhaust line is closed. A reactant is produced by supplying a reactant gas that reacts with the unreacted source gases in the exhaust line. An inert gas is supplied to the exhaust line. Next, the inside of the exhaust line is reacted with the atmosphere. During the atmospheric reaction, the reaction between the incoming atmospheric gas and the remaining reactant is delayed by the inert gas.

Description

Substrate processing apparatus and method {Apparatus and Method of Processing wafer}

The present invention relates to a substrate processing apparatus and method, and more particularly, to a substrate processing apparatus and method including an exhaust apparatus.

As one of the semiconductor layer deposition methods, the ALD (atomic layer deposition) method can easily cover a step difference and can produce a thin film in Angstrom units.

The ALD method periodically performs the steps of providing a source gas made of an organometallic precursor, purging the remaining source gas, providing a reactant, and purging the remaining reactive gas, A method of depositing a semiconductor layer.

A purge step of removing residual source gas and reactive gas is performed through an exhaust system including a pump. In addition to the purge process, an exhaust process in the exhaust line is being performed for maintenance of the substrate processing apparatus.

The exhaust process may consist of solidifying a source gas component remaining in the exhaust gas and subjecting the solidified source component to atmospheric reaction.

However, during the atmospheric reaction, as a large amount of atmospheric gas flows into the exhaust line, a rapid reaction with the source component remaining in the exhaust line proceeds, causing heat generation and fire.

An object of the present invention is to provide a substrate processing apparatus and method capable of improving exhaust performance.

A substrate processing apparatus according to an embodiment of the present invention includes: a process chamber having a processing space and including a susceptor for seating at least one substrate; a gas injection unit mounted on the process chamber and provided to respectively inject a first process gas including a source gas and a second process gas including a reaction gas to the substrate; and a first exhaust block connected to a first exhaust pump to discharge the first process gas remaining in the processing space and including an atmospheric inlet valve controlling the inflow of atmospheric gas, and installed to be spaced apart from the first exhaust block; an exhaust unit including a second exhaust block connected and connected to a second exhaust pump to discharge a second process gas remaining in the processing space, wherein the first exhaust block includes a reactive gas supply unit for supplying a reactive gas and an inert It further includes an inert gas supply unit for supplying a gas. During maintenance of the first exhaust block, a reactant is formed by reacting the first process gas remaining in the first exhaust block with the reaction gas supplied through the reaction gas supply unit, and the first process gas remaining in the first exhaust block is introduced into the first exhaust block. and a controller configured to control the reaction gas supply unit, the inert gas supply unit, and the atmospheric inlet valve to delay a reaction between the reactant and the atmospheric gas by the inert gas supplied from the inert gas supply unit.

Also, according to an embodiment of the present invention, there is provided a method for maintaining a substrate processing apparatus, the method comprising: discharging the first process gas remaining in the process chamber through the first exhaust line; closing a first main exhaust valve on the first exhaust line; supplying the reactant gas downstream of the first main exhaust valve to react with the unreacted first process gas in the first exhaust line to generate a reactant; and introducing the atmospheric gas through the atmospheric inlet valve on the first exhaust line to react the reactant remaining in the first exhaust line with the atmospheric gas. The method may further include: supplying the inert gas to one exhaust line to delay a reaction between the reactant and the atmospheric gas when the atmospheric gas is introduced.

According to the present invention, the reaction rate between the residual process gas and the atmospheric gas can be reduced by filling the exhaust line with an inert gas during the standby process for maintenance of the exhaust part, thereby reducing the atmospheric gas inflow rate.

1 and 2 are cross-sectional views of a substrate processing apparatus according to an embodiment of the present invention.
3 and 4 are flowcharts illustrating a substrate processing method according to an embodiment of the present invention.

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention belongs It is provided to fully inform the possessor of the scope of the invention, and the present invention is only defined by the scope of the claims. Sizes and relative sizes of layers and regions in the drawings may be exaggerated for clarity of description. Like reference numerals refer to like elements throughout.

1 is a cross-sectional view of a substrate processing apparatus according to an embodiment of the present invention.

Referring to FIG. 1 , the substrate processing apparatus 10 of this embodiment includes a process chamber 100 , a gas injection unit 200 , an exhaust unit 300 , a reactive gas supply unit 400 , and an inert gas supply unit 500 . can do.

The process chamber 100 may include a substrate processing space therein, and may include a susceptor 101 in which at least one substrate 102 may be accommodated. The susceptor 101 may serve as a table for stably supporting the substrate 102 during a substrate processing process. The susceptor 101 may serve as a temperature control device by including a heating heater inside or at the bottom thereof. In addition, the process chamber 100 may include a bottom portion 103 , an outer wall portion 104 , and an upper layer plate 105 to block the inflow of external air.

The gas injection unit 200 is located near the upper plate 105 of the process chamber 100 and injects at least one, for example, the first and second process gases 201a and 202a into the process chamber 100 . can supply

For example, the gas injection unit 200 may include a plurality of shower heads to provide the first process gas 201a and the second process gas 202a onto the substrate 102 . That is, the gas injection unit 200 may include a first process gas injection unit 200a, a second process gas injection unit 200b, and a purge gas injection unit 200c. The first process gas ejection unit 200a and the second process gas ejection unit 200b may be radially disposed along the circumferential direction of the gas ejection unit 200, and the first and second process gas ejection units 200a, The purge gas injection unit 200c may be provided between 200b) or in the middle of the gas injection unit 200 .

The substrate processing apparatus 10 of the present exemplary embodiment is a space division type processing apparatus, and the susceptor 101 and the gas injection unit 200 rotate relative to each other to simultaneously process the plurality of substrates 102 . That is, the first process gas, the purge gas, the second process gas, and the purge gas injected from the gas injector 200 onto any one of the plurality of substrates 102 seated on the susceptor 101 . The susceptor 101 may be rotated or the gas injection unit 200 may be rotated so that the ions may be sequentially supplied.

Here, the first process gas 201 may be a source gas including a metal precursor, and the second process gas 202 may include a reactive gas. The first process gas 201 may include one gas selected from Zr, Ti, Si, Ta, and Hf, but is not limited thereto. The second process gas 202 reacts with the first process gas to form an atomic layer on the substrate, and O2, O3, or NH3 may be used.

In this embodiment, when a zirconium source such as CpZr[N(CH3)2]3 or Zr(N(CH3)(C2H5))4 is used as the first process gas 201a, O3, O2, H2O, or OH It can be used as the second process gas 202 . In addition, when a titanium source such as TiCl4 is used as the first process gas 201 , O3, O2, or NH3 may be used as the second process gas 202 . Also, when a silicon source such as Si2Cl6, C8H22N2Si, or C3H22N2Si is used as the first process gas 201 , O3, O2, or NH3 may be used as the second process gas 202 .

The exhaust unit 300 is configured to exhaust the first and second process gases 201a and 202a remaining in the process chamber 100 to the outside.

The exhaust unit 300 of this embodiment may be located below the process chamber 100 . The exhaust unit 300 may include a first exhaust block 310a for discharging the first process gas and a second exhaust block 310b for discharging the second process gas.

The first exhaust block 310a may include a first exhaust line L1 and a first main exhaust valve MV1.

The first exhaust line L1 may be a line connecting the process chamber 100 and the first exhaust pump 340a. The first main exhaust valve MV1 may be located on the first exhaust line L1 to control the discharge of the first process gas from the process chamber 100 . For example, the first main exhaust valve MV1 may be used as an atmospheric inlet valve. Also, the first exhaust block 310a may further include a plasma processing unit 320 and a powder collecting unit 330 positioned downstream of the first main exhaust valve MV1 .

The plasma processing unit 320 may be located on the first exhaust line L1 between the first main exhaust valve MV1 and the powder collecting unit 33 . During the purge process or other exhaust process, the unreacted first process gas 201 in the process chamber 100 is transferred to the plasma processing unit 320 by driving the pump 340a. The plasma processing unit 320 plasma-treats the introduced first process gas 201 through a general plasma process, dissociates it into a stable state, and solidifies it. The plasma processing unit 320 may include an internal space (not shown) in which plasma is to be formed, and plasma processing may be performed in the internal space. In addition, the plasma processing unit 320 may additionally include an atmospheric inlet valve (not shown) for selectively introducing the atmosphere into the internal space.

The powder collecting unit 330 is positioned between the plasma processing unit 320 and the first pump 340a to additionally collect powder generated in the process chamber 100 and powder that may be generated in the plasma processing unit 320 . . The powder collecting unit 330 may apply, for example, a cold trap or a hot trap, and may be replaced periodically.

The reaction gas supply unit 400 supplies the second process gas to the second process gas injector 200b and simultaneously supplies the second process gas to at least one part of the exhaust line L1 of the first exhaust block 310a. can be provided as a reaction gas.

A reaction gas corresponding to the second process gas 202 provided to the second process gas injector 200b may react with the first process gas in the process chamber 100 to deposit a semiconductor layer. Meanwhile, the reaction gas provided in the first exhaust line L1 of the first exhaust block 310a further reacts with the first process gas component remaining in the first exhaust line L1 to generate a reactant. can

That is, even if the first process gas 201a exhausted from the process chamber 100 goes through the plasma processing unit 320 and the powder collection unit 330 to be solidified and the powder collection process is performed, residual by-products are removed from the first exhaust. Since it may remain in the line L1 , the inner diameter of the first exhaust line L1 may be reduced.

Accordingly, in the present embodiment, the reaction gas may be additionally supplied to the first exhaust line L1 to react the unreacted first process gas (source gas) with the reaction gas to generate a reactant. When the reactant is generated, the first main exhaust valve MV1 may proceed in a closed state.

In this case, the reactive gas supply unit 400 and the inert gas supply unit 500 may be connected to a predetermined portion of the first exhaust line L1 . The reaction gas supply unit 400 may be connected to the first exhaust line L1 by an integrated line L11 and a first branch line L12 . The integrated line L11 may be branched from the first exhaust line L1 , and the first branch line L12 may be branched from the integrated line L11 . The first valve V1 may be installed on the first branch line L12 to control the introduction of the reaction gas corresponding to the second process gas 202a. The supply of the reaction gas to the first exhaust line L1 may be continuously supplied not only in the deposition process step (purge step during deposition) but also in the maintenance step.

The inert gas supply unit 500 may be connected to at least a portion of the first exhaust line L1 to fill the interior of the first exhaust line L1 with an inert gas such as Ar or N2. The inert gas supply unit 500 may supply the inert gas to change the pressure inside the first exhaust line L1 to a range similar to normal pressure, for example, 740 to 760 Torr. Accordingly, thereafter, during the atmospheric reaction for removing the reactant, the inflow rate of the atmospheric gas may be adjusted. The inert gas supply unit 500 may be connected to the first exhaust line L1 through the integrated line L11 and the second branch line L13 . As described above, the integrated line L11 may be branched from the first exhaust line L1 , and the second branch line L13 may be branched from the integrated line L11 like the first branch line L12 . . In addition, a second valve V2 is provided on the second branch line L13 to selectively control the inert gas flowing into the first exhaust line L1. Here, the first main valve MV1 may be located upstream of a connection portion between the first exhaust line L1 and the integrated line L11, as shown in FIG. 1 .

Also, as shown in FIG. 2 , the first main valve MV1 may be located upstream of a connection portion between the first exhaust line L1 and the integrated line L11, and the first exhaust line L1 An additional atmospheric inlet valve MV3 may be further provided downstream of the connection portion of the and integration line L11.

When the inert gas at the atmospheric pressure level is filled in the first exhaust line L1, the inflow rate of the atmospheric gas may be reduced during the atmospheric reaction for removing the residual powder. Accordingly, the reaction between the first process gas by-product that may remain in the first exhaust line L1 and the O2 or H2O gas, which is an atmospheric gas, becomes slow. Therefore, the reaction rate of the atmospheric gas and the first process gas by-product, which may include an organometallic component, is reduced, thereby reducing heat generation and ignition problems. Here, the unexplained reference numeral V3 may be a third valve that blocks the operation of the pump 340a.

Meanwhile, the first pump 340a is located outside the exhaust unit 300 and is configured to adjust the pressure inside the process chamber 100 . That is, the first pump 340a may control the pressure of the process chamber 100 to discharge the unreacted first process gas to the first exhaust line L1 outside the process chamber 100 .

A scrubber 350 may be further connected to the downstream side of the first pump 340a. The scrubber 350 is configured to collect contaminants remaining even after the pumping process.

Meanwhile, the second exhaust block 310b may include a second exhaust line L2 and a second main exhaust valve MV2 positioned on the second exhaust line L2. The second main exhaust valve MV2 may control the introduction of the second process gas into the second exhaust line L2 . The second exhaust line L2 may be connected to the second exhaust pump 340b.

Since the second exhaust block 310b discharges only a reactive gas such as O2 or O3, a separate solidification treatment unit is not required.

In addition, the substrate processing apparatus 10 of the present embodiment may further include a control block 600 for controlling each component of the exhaust unit 300 . The control block 600 determines whether the respective valves M1V1, MV2, V1 to V3 connected to the first and second exhaust lines L1 and L2 are opened or closed, as well as the driving order and driving time of the pumps 340a and 340b. can be controlled. The function of the control block 600 is not limited thereto, and may include a function to individually control various components of the substrate processing apparatus 10 .

2 and 3 are flowcharts for explaining a substrate processing method according to an embodiment of the present invention.

First, the first main exhaust valve MV1 is closed (S1). Thereafter, the remaining first process gas 201a in the process chamber 110 is removed from the first exhaust block ( 310), and then solidified in the first exhaust line L1. The solidification treatment may be performed through the processing operation of the plasma processing unit 320 and the collection operation of the powder collecting unit 330 . Each of the plasma treatment step and the powder collection step may be performed at least once or more.

Next, a reaction gas corresponding to the second process gas 202a is provided in the first exhaust line L1 (S2). Accordingly, unreacted first process gases that may remain in the first exhaust line L1 may react with the injected reactive gas to form a removable reactant. The reaction gas may be supplied, for example, for 50 to 70 minutes. In the reaction gas supply step, the inert gas provided from the inert gas supply unit 500 may be additionally supplied for a predetermined time period, for example, 5 to 15 minutes, so that the purge may proceed simultaneously.

After that, while the first main exhaust valve MV1 is still closed, the third valve V3 is closed and the second valve V2 is opened to release an inert gas into the first exhaust line L1. supply (S3). The inert gas may be supplied until the pressure inside the first exhaust line L1 maintaining a negative pressure state reaches the atmospheric pressure level.

After that, an atmospheric reaction inside the first exhaust line L1 is performed (S4). The atmospheric reaction may be a process of exposing the reactants of the reactant gas and the source gas remaining in the first exhaust line L1 to the atmospheric gas in order to remove them through a reaction with the atmospheric gas. The waiting process may be performed, for example, for about 11 to 13 hours. At this time, even when exposed to atmospheric gas for a long time, since the inert gas is filled in the first exhaust line L1, the inflow rate of atmospheric gases such as O2 and H2O is reduced. Accordingly, since the reaction rate between the atmospheric gas and the remaining first process gas components is also reduced, the problems of heat generation and ignition due to the sudden reaction can be solved.

Thereafter, as shown in FIG. 3 , after completing the standby process, the temperature inside the first exhaust line L1 is measured, and when the temperature is below a certain temperature Tc, the maintenance step of the exhaust unit 300 is performed. and, if not, the standby process is performed again (S5). At this time, the constant temperature (Tc) may be 35 to 45 ℃.

According to the present invention, the reaction rate between the residual process gas and the atmospheric gas can be reduced by filling the exhaust line with an inert gas during the standby process for maintenance of the exhaust part, thereby reducing the atmospheric gas inflow rate.

Although the present invention has been described in detail with reference to a preferred embodiment, the present invention is not limited to the above embodiment, and various modifications can be made by those skilled in the art within the scope of the technical spirit of the present invention. do.

300: exhaust unit 310a: first exhaust block
310b: second exhaust block 320: plasma processing unit
330: powder collecting unit 340a, 340b: pump
400: reactive gas supply unit 500: inert gas supply unit

Claims (15)

a process chamber having a processing space and including a susceptor for seating at least one substrate;
a gas injection unit mounted on the process chamber and provided to respectively inject a first process gas including a source gas and a second process gas including a reaction gas to the substrate; and
a first exhaust block connected to a first exhaust pump to discharge the first process gas remaining in the processing space and including an atmospheric inlet valve controlling the inflow of atmospheric gas; and an exhaust unit including a second exhaust block connected to and connected to a second exhaust pump to exhaust a second process gas remaining in the space;
The first exhaust block further includes a reactive gas supply unit for supplying a reactive gas and an inert gas supply unit for supplying an inert gas,
During maintenance of the first exhaust block, reacting the first process gas remaining in the first exhaust block with the reaction gas supplied through the reaction gas supply unit to form a reactant;
Controlling the reaction gas supply unit, the inert gas supply unit and the atmospheric inlet valve to delay the reaction between the reactant and the atmospheric gas by the inert gas supplied from the inert gas supply unit into the first exhaust block A substrate processing apparatus including a control unit. The method of claim 1,
The control unit is
on/off controlling the reactive gas supply unit to supply the reactive gas into the first exhaust block through the reactive gas supply unit;
After the supply of the reactive gas is stopped, on/off control of the inert gas supply unit to supply the inert gas into the first exhaust block,
and turn on/off the atmospheric inlet valve to introduce the atmospheric gas into the first exhaust block after the supply of the inert gas is stopped;
The control unit controls the reaction gas supply unit, the inert gas supply unit, and the atmosphere inlet valve to be sequentially driven. The method of claim 1,
The first exhaust block,
a first exhaust line for exhausting the first process gas from the process chamber;
a first exhaust line connecting the process chamber and the first exhaust pump;
a first main exhaust valve installed on the first exhaust line to regulate the inflow of the first process gas into the first exhaust line;
The atmospheric inlet valve is provided downstream of the first main exhaust valve. 4. The method of claim 3,
The reaction gas supply unit,
The substrate processing apparatus is provided between the first main exhaust valve and the atmospheric inlet valve and configured to supply a reaction gas to the first exhaust line. 4. The method of claim 3,
The inert gas supply unit,
The substrate processing apparatus is provided between the first main exhaust valve and the atmospheric inlet valve to supply the inert gas to the first exhaust line. 4. The method of claim 3,
The first exhaust block,
a plasma processing unit provided between the first exhaust pump and the first main exhaust valve and stabilizing the first process gas and the reactive gas by plasma processing;
and a powder collecting unit disposed between the plasma processing unit and the first exhaust pump and collecting powder reacted through the plasma processing unit. 7. The method of claim 6,
The atmospheric inlet valve is further provided in the plasma processing unit. 7. The method of claim 6,
The reaction gas supply unit,
The substrate processing apparatus is provided between the first main exhaust valve and the plasma processing unit to supply the reaction gas reacting with the first process gas onto the first exhaust line. 7. The method of claim 6,
The inert gas supply unit,
The substrate processing apparatus is provided between the first main exhaust valve and the plasma processing unit to supply the inert gas onto the first exhaust line. The method of claim 1,
The first exhaust block,
Further comprising a temperature measuring unit for measuring the temperature on the first exhaust block,
the control unit
A substrate processing apparatus outputting a maintenance start signal when the temperature value measured by the temperature measuring unit is equal to or less than a set temperature. The method of claim 1,
The first process gas includes a zirconium-containing source, a titanium-containing source, and a silicon phosphor.
It is one selected from the ham sauce,
The second process gas is one of O ₃ , O ₂ , H ₂ O, and OH gas. 4. A method for maintaining the substrate processing apparatus of claim 3, comprising:
discharging the first process gas remaining in the process chamber through the first exhaust line;
closing a first main exhaust valve on the first exhaust line;
supplying the reactant gas downstream of the first main exhaust valve to react with the unreacted first process gas in the first exhaust line to generate a reactant;
Including; introducing the atmospheric gas through the atmospheric inlet valve on the first exhaust line to react the reactant remaining in the first exhaust line with the atmospheric gas;
The step of reacting the atmospheric gas,
supplying the inert gas to the first exhaust line before introducing the atmospheric gas to delay the reaction between the reactant and the atmospheric gas when the atmospheric gas is introduced; Way. 13. The method of claim 12,
The first exhaust block,
a plasma processing unit provided between the first exhaust pump and the first main exhaust valve to plasma-process the first process gas and the reaction gas;
Further comprising a powder collecting unit provided between the plasma processing unit and the first exhaust pump,
The step of reacting the atmospheric gas is performed in the plasma processing unit,
The maintenance method of the substrate processing apparatus, wherein the powder generated through the step of reacting the atmospheric gas is collected through the powder collecting unit. 13. The method of claim 12,
After reacting the atmospheric gas,
When the temperature of at least one part of the first exhaust block is measured and is below the set temperature, the maintenance step of the exhaust part is performed,
The maintenance method of a substrate processing apparatus, characterized in that the step of reacting the atmospheric gas is continued when the temperature is higher than the set temperature. 15. The method of claim 14,
The set temperature is a maintenance method of a substrate processing apparatus, characterized in that 35 ℃ to 45 ℃.

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