KR101869949B1 - Deposition method for multilayer and substrate process apparatus - Google Patents

Abstract

The present invention relates to a composite film deposition method and a substrate processing apparatus, and more particularly, to a composite film deposition method for repeatedly depositing different thin films alternately on a substrate using plasma generated in a chamber, A measuring step of measuring a current value for adjusting the chamber impedance; and an impedance adjusting step of adjusting the current value so that a current value measured in the measuring step is included in a reference setting range, .

Description

TECHNICAL FIELD The present invention relates to a multilayer film deposition method,

The present invention relates to a composite film deposition method and a substrate processing apparatus, and more particularly, to a composite film deposition method and a substrate processing apparatus capable of improving the uniformity of a thin film.

Generally, a semiconductor device and a flat panel display are manufactured by depositing a plurality of thin films on an upper surface of a substrate and etching them to form elements of a predetermined pattern. That is, a thin film is deposited on the entire surface of a substrate using a deposition apparatus, and a thin film is etched by using an etching apparatus so that the thin film has a predetermined pattern, thereby manufacturing a semiconductor device or a flat panel display.

The thin film can be formed by various processes, and a chemical vapor deposition (CVD) process in which a thin film is formed by supplying a gaseous raw material into a reaction chamber into which a substrate is introduced is mainly used. In addition, as the substrate is enlarged, the device is miniaturized and highly integrated, the plasma is used, and the etching process as well as the thin film deposition using the gas activated by the plasma is also proceeding. In this plasma CVD process, after the substrate is placed on the substrate support in the reaction chamber, the reaction gas is injected through the gas injection body, RF power is applied to activate the reaction gas, and a predetermined film is deposited on the substrate. On the other hand, when a thin film is deposited on a substrate, different kinds of thin films such as a nitride film and an oxide film can be repeatedly deposited in an in-situ manner. In other words, in the case of depositing the oxide film, the initial process conditions (I _A1 ) such as the pressure inside the chamber, the temperature, the distance between the gas jet and the substrate support, the RF power and the like and the later process conditions (I _A2 ) Can be deposited in a fixed state with the condition (I _A1 = I _A2 ). Also, in the case of the nitride film, the initial process conditions (I _B1 ) in which the initial thin film is deposited and the later process conditions (I _B2 ) in the subsequent deposition can both be fixed to the same condition (I _B1 = I _B2 ).

However, in the case of depositing an oxide film, depositing a nitride film, and then depositing an oxide film, heterogeneous thin films are successively deposited without performing a separate cleaning process. Accordingly, in the process of depositing the thin film, the chamber internal environment is different from that when the initial thin film is deposited, for example, the chamber impedance is changed by depositing the thin film deposition material or particles inside the chamber. Therefore, if the thin film is formed by maintaining the initial process conditions and the later process conditions (I _B1 = I _B2 ), the uniformity of the thin film deposited later becomes lowered.

KR 2007-102764 A KR 10-0813564 B

The present invention provides a composite film deposition method and a substrate processing apparatus capable of continuously forming different kinds of thin films.

The present invention provides a composite film deposition method and a substrate processing apparatus capable of improving deposition uniformity of a thin film.

The present invention provides a composite film deposition method and a substrate processing apparatus capable of improving the quality and productivity of a thin film.

A composite film deposition method according to an embodiment of the present invention is a composite film deposition method for repeatedly depositing different thin films alternately on a substrate using a plasma generated in a chamber, A measurement step of measuring a current value for adjusting an internal impedance of the sensor; and an impedance adjustment step of adjusting the current value so that the current value measured in the measurement step is included within a reference setting range.

The measuring step and the impedance adjusting step may be repeatedly performed so that the current value measured in the measuring step is included in the reference setting range.

The different thin films can be deposited in situ in the same chamber.

The composite film can be alternately deposited with an oxide film and a nitride film.

The impedance adjusting step may include a step of determining whether a current value measured in the measuring step is included in a reference setting range, and adjusting the height of the substrate supporting part in the chamber or the gas spraying body The power value to be applied can be adjusted.

The impedance adjusting step may maintain the predetermined height of the substrate supporting part or the power value applied to the gas jetting body when the current value measured in the measuring step is within the reference setting range.

The impedance adjusting step may adjust the height of the substrate supporting part such that the thin film is an oxide film and the measured current value is within a reference setting range when the current value measured in the measuring step is out of the reference setting range .

The impedance adjustment step may include adjusting the impedance value of the gas sprayer such that the thin film is a nitride film and the measured current value is within the reference setting range when the current value measured in the measuring step is out of the reference setting range Can be adjusted.

A substrate processing apparatus according to an embodiment of the present invention is a substrate processing apparatus for forming a composite film by repeatedly depositing different thin films alternately in a chamber, wherein the substrate processing apparatus is provided inside the chamber and supports the substrate, A substrate supporting part which is driven to move up and down; A gas spraying unit provided on the substrate support unit to supply a process gas to the substrate support unit; A plasma generator for generating plasma in the chamber by applying plasma power to the gas injector; A measuring unit for measuring a current value for adjusting an impedance of the inside of the chamber; And a controller for adjusting the measured current value so that a current value input from the measuring unit is included in a predetermined range before depositing each thin film on the substrate.

In the substrate processing apparatus, an oxide film and a nitride film can be alternately deposited.

The control unit may determine whether or not the current value input from the measurement unit is included in the reference setting range and adjust the height between the gas jetting member and the substrate supporting unit by the elevation driving unit in the chamber Or the power value applied to the gas jetting body can be adjusted.

Wherein the control unit controls the gas injecting body and the gas injecting body so that the thin film is an oxide film and the measured current value is within the reference setting range when the current value inputted from the measuring unit is out of the reference setting range, It is possible to control to adjust the height between the substrate supporting portions.

Wherein the control unit controls the power value applied to the gas sprayer such that the thin film is a nitride film and the measured current value is located within the reference setting range when the current value input from the measurement unit is out of the reference setting range Can be controlled.

The composite film deposition method and the substrate processing apparatus according to the embodiments of the present invention can continuously and uniformly form different kinds of thin films. Thin film deposition material or particles generated in the process of depositing a thin film are deposited inside the chamber to change the internal environment of the chamber, so that the thin film can be uniformly formed by controlling the process conditions. The defective deposition of the thin film can be suppressed, and the productivity can also be improved.

1 is a schematic view showing a configuration of a substrate processing apparatus according to an embodiment of the present invention;
2 is a flow chart illustrating a process of depositing a thin film using a composite film deposition method according to an embodiment of the present invention.
FIG. 3 is a graph showing changes in current values before and after a process condition is compensated in the deposition of an oxide film.
FIG. 4 is a graph showing changes in current values before and after a process condition is compensated in a nitride film deposition.
FIG. 5 is a graph comparing changes in impedance current values before and after a process condition is compensated for by a composite film deposition method according to an embodiment of the present invention during oxide film deposition, and variations in uniformity.
FIG. 6 is a graph comparing changes in the impedance current values before and after the process conditions are compensated for by the composite film deposition method according to the embodiment of the present invention during the nitride film deposition, and variations in the uniformity.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It will be apparent to those skilled in the art that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, It is provided to let you know.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a schematic view showing a configuration of a thin film production apparatus according to an embodiment of the present invention.

Referring to FIG. 1, a thin film production apparatus includes a chamber 10, a substrate support 30, and a gas jet 20. It also includes a gas supply source for supplying various gases to the gas jetting body 20 and a means for applying power to the gas jetting body.

The chamber 10 has a main body 12 with an open top and a top lead 11 which is openably and closably provided on the top of the main body 12. [ When the top lead 11 is coupled to the upper portion of the main body 12 to close the inside of the main body 12, a space for processing the substrate S such as a deposition process is formed in the chamber 10 . Since the space portion is generally formed in a vacuum atmosphere, an exhaust port for discharging the gas existing in the space portion is formed at a predetermined position of the chamber 10, and the exhaust port is connected to the exhaust pipe 50 ). Further, on the bottom surface of the main body 12, a through hole is formed in which a support shaft of a substrate supporting portion 30 to be described later is inserted. A gate valve (not shown) is formed on the side wall of the main body 12 to carry the substrate S into or out of the chamber 10.

The substrate support 30 has a substrate support 31 and a support shaft 32 for supporting the substrate S. The substrate support 31 is horizontally disposed inside the chamber 10 in a disc shape and the support shaft 32 is vertically connected to the bottom surface of the substrate support 31. The support shaft 32 is connected to an elevation drive means (not shown) of an external motor or the like through a through hole to move the substrate support table 31 up and down. In addition, a heater (not shown) is provided on the lower side or inside of the substrate support 31 to provide an electrode for heating the substrate S to a predetermined process temperature and generating a plasma. For example, it can be heated and maintained in the range of 100 to 560 degrees.

The gas spraying body 20 is spaced apart from the upper portion of the substrate supporting portion 30 and injects a process gas such as a raw material, a carrier gas, a reaction gas, and an auxiliary gas, which have been vaporized to the substrate supporting portion 30 side. The gas jetting body 20 is a showerhead type in which different types of gases introduced from the outside are mixed and jetted toward the substrate S. Of course, various types of injectors such as injectors and nozzles may be used as the gas jetting body 20 in addition to the showerhead type.

The gas jetting body 20 is connected to a gas supply source and a gas supply line for supplying various process gases. First, a first raw material supply source 71 for supplying the first raw material, a first raw material supply line 81 connected between the first raw material supply source 71 and the gas injector 20, And a first valve 91 provided on the material supply line 81 for controlling the supply of the first raw material.

The first raw material supply source 71 includes a storage means for storing the first raw material in a liquid phase, a vaporizing means for supplying the liquid raw material in the liquid phase and for vaporizing the raw raw material, and a carrier gas supply means for storing and supplying the carrier gas do. At this time, the vaporizing means can use a vaporizer or a bubbler, which is a general means, and thus a detailed description thereof will be omitted. A discharge line through which the vaporized first raw material is discharged is connected to a discharge line of the carrier gas supply means, and these discharge lines are connected to the first raw material supply line 81. A discharge line (not shown) through which the raw material is discharged may be connected between the first source material supply source 71 and the exhaust pipe 50 of the chamber 10. A first reaction gas supply source 72 and a first reaction gas supply line 82 for supplying a first reaction gas are connected to the gas jet 20 and a first reaction gas supply line 82 is connected to the first reaction gas supply line 82. [ And a second valve 92 for controlling the supply of the gas. The first raw material supply line 81 and the first reaction gas supply line 82 are coupled to the outside of the chamber before being connected to the gas jet 20 and a main control valve 90 is provided . Of course, the first raw material supply line 81 and the first reaction gas supply line 82 may be connected to the gas injector 20 to supply the respective gases, respectively.

A second raw material supply source 73 for supplying the second raw material, a second raw material supply line 83 connected between the second raw material supply source 73 and the gas injector 20, And a third valve 93 provided on the material supply line 83 for controlling the supply of the second raw material. The second raw material supply source 73 includes a storage means for storing the second raw material in a liquid state like the first raw material supply source 71, a vaporizing means for supplying the liquid raw material to the second raw material and vaporizing the second raw material, And a carrier gas supply means for storing and supplying the carrier gas. A discharge line through which the vaporized second raw material is discharged is connected to a discharge line of the carrier gas supply means, and these discharge lines are connected to the second raw material supply line 83.

A second reaction gas supply source 74 and a second reaction gas supply line 84 for supplying a second reaction gas are connected to the gas jet 20 and a second reaction gas supply line 84 is connected to the second reaction gas supply line 84. [ And a fourth valve 92 for controlling the supply of the fuel. The second raw material supply line 83 and the second reaction gas supply line 84 are coupled to each other outside the chamber before being connected to the gas jet 20 and the main control valve 90 is provided on the coupling line . Of course, the second raw material supply line 83 and the second reaction gas supply line 84 may be respectively connected to the gas jet 20 to supply the respective gases.

The gas jetting body 20 is provided with a purge gas supply source 75 for supplying a purge gas and a purge gas supply line 85 and a purge gas supply line 85 connected to the purge gas supply source 75, And a fourth valve 94 for controlling the supply of the gas. The purge gas supply source 75 removes the source gas, the reaction gas, and the residue remaining in the chamber 10 after or during the deposition of the thin film.

Here, the first source gas and the second source gas may be the same type or different types depending on the type of the thin film to be deposited. Also, the first reaction gas and the second reaction gas may be the same or different kinds of gases. Although two gas sources and two reactive gases are described here, two or more source gases and reaction gases may be used depending on the kind of the deposited thin film.

The thin film production apparatus is provided with a plasma generation section. That is, a plasma generating unit may be provided in order to generate plasma in the chamber to excite various process gases into an active species state. The power supply means 60 is connected to the gas jetting body 20, for example. A matching device 62 is provided between the power supply means 60 and the gas jetting body 20 and is controlled through the control unit 64. RF power is applied to the gas jet 20 on the substrate 10 of the chamber 10 and the substrate support 31 is grounded to apply plasma to the reaction space as the deposition space in the chamber using RF power And may be driven by Capacitively Coupled Plasma (CCP). The method of using the plasma for the thin film has an advantage that the reactive gas can be easily activated even at a low temperature, and a high quality thin film can be formed by applying less energy at a high temperature. Wherein the RF power can use at least one of a high frequency RF power and a low frequency RF power. That is, both the high frequency RF power and the low frequency RF power may be applied to the gas jetting body 20, or may be applied alone. Here, the frequency band of the high frequency RF power is about 3 to 30 MHz, the frequency band of the low frequency RF power is about 30 to 3000 KHz, and for example, a high frequency RF power having a frequency of 13.56 MHz and a low frequency RF power having a frequency of 370 KHz can be used. The high frequency RF power can be used in the range of about 100 to 1000 watts, and the low frequency RF power can be used in the range of 0 to 600 watts. Further, a matching device 62 may be provided between the power supply means 60 and the gas jetting body.

The matching unit 62 supplies high-frequency RF power or low-frequency RF power to the gas injector, matches the low-frequency RF power to high-frequency RF power, and supplies the high-frequency RF power to the gas injector. In the latter case, it is preferable to adjust the total power of the high frequency RF power and the low frequency RF power to be in the range of 100 to 1300 watts, or the high frequency RF power may be varied in the range of 100 to 1000 watts, or the low frequency RF power may be in the range of 10 to 600 watts It is good to change. At this time, the RF power is a range required for decomposing or activating the raw material and the reaction gas. In addition, the matching device 62 generates an impedance capable of canceling the impedance of the chamber 10, so that maximum power is supplied to the chamber 10 so that an optimum plasma is generated. In the present invention, a measuring unit, for example, a current measuring device capable of measuring current, is provided in the matching unit 62 to measure a change in the impedance of the chamber 10.

In addition to the above, the plasma generating portion may include a coil to generate a plasma by an induction method. A remote plasma method may be implemented in which the gas is made into an active species state by plasma excitation outside the chamber 10 or in a gas jet body 20 coupled with the chamber and supplied to the substrate, Can be applied.

The control unit 64 controls the current supplied to the substrate supporting unit 30 based on the current value in the chamber measured by the current measuring unit in the matching unit 62 to compensate for the impedance of the chamber 10 which is changed in the process of depositing the thin film on the substrate. And the power value supplied from the power supply means 60 is adjusted. Accordingly, a database of the height and the power value of the substrate supporter 30 to be adjusted corresponding to the current value measured by the current meter can be stored in the control unit.

When the deposition process is performed in the thin film production apparatus constructed as described above, various process gases are supplied to the upper portion of the substrate S through the gas injection body 20, plasma is formed in the chamber 20, And the residual gas and the by-product are discharged to the outside through the exhaust pipe 50. [0041] Of course, the thin film manufacturing apparatus can be variously changed other than the above description.

Hereinafter, the thin film deposition method of the present invention will be described by way of examples.

FIG. 2 is a flow chart showing a process of depositing a thin film using the composite film deposition method according to an embodiment of the present invention, FIG. 3 is a graph illustrating Table 1, and FIG. 4 is a graph illustrating Table 2.

The thin film manufacturing method includes the steps of providing a substrate and mounting the substrate on a substrate support in a chamber (S112), controlling the atmosphere inside the chamber, controlling the substrate temperature (S114), supplying a process gas into the chamber, Steps S122 and S132, and a step S138 of taking the substrate out of the chamber.

In addition, in the present invention, in order to make the inside of the chamber capable of depositing the optimum thin film in accordance with the change of the environment inside the chamber in the process of repeatedly depositing the thin film on the substrate before the thin film is deposited on the substrate, (S110) of preparing a database of process conditions capable of adjusting the internal environment of the chamber correspondingly. (S116, S118, S120, S126, S128, S130) of changing the process condition according to the environment inside the chamber, that is, the impedance change, using the database prepared in advance in the process of depositing the thin film .

When the heterogeneous thin film composed of the first thin film and the second thin film is continuously and repeatedly deposited, the initial environment inside the chamber is set to the optimum environment in which the first thin film and the second thin film can be formed with desired quality and thickness have. However, as the number of deposition times of the first thin film and the second thin film increases, particles or thin film forming materials adhere to the inside of the chamber, and the initial environment can not be maintained. The impedance of the chamber is an element that can be measured. That is, as the number of times of deposition of the first thin film and the second thin film increases, the impedance of the chamber increases and the plasma becomes unstable, thereby reducing the uniformity of the thin film deposited on the substrate.

Accordingly, in the present invention, the uniformity of the hetero-film can be improved by maintaining the impedance of the chamber, that is, the current value measured by the current meter of the matching device, constantly by changing the process conditions in accordance with the change of the environment in the chamber. The database for keeping the impedance of the chamber constant can be prepared as follows.

The substrate is loaded on top of the substrate support in the chamber, and the atmosphere in the chamber and the substrate temperature are controlled. Subsequently, a process gas is supplied into the chamber, and a plasma is generated to deposit a thin film on the substrate. Deposition of the thin film may alternately and repeatedly deposit the first thin film and the second thin film on the substrate, and the deposition of the first thin film and the second thin film may be deposited in situ.

Before depositing the thin film, current can be measured using a current meter in the matching device. As the impedance of the chamber is changed, the current value measured by the current meter is also changed. The particles or the thin film forming material that is generated when the thin film is deposited is deposited inside the chamber, and as a result, the impedance decreases as the thin film deposition number increases. Therefore, the current value measured by the current meter increases.

Thus, in the present invention, the impedance of the chamber can be kept constant by keeping the current value which is an index of the impedance constant. Process conditions that affect the impedance of the chamber may include a power value applied for plasma formation and a distance between the substrate support and the gas jetting body (hereinafter referred to as a 'gap').

Accordingly, in order to maintain the impedance constant, the present invention provides a database for adjusting the internal environment of the chamber, that is, the impedance, by measuring the power value and the change of the current value measured by the current meter while adjusting the gap.

Tables 1 and 2 below show current values measured while adjusting gap and power values according to the deposition number of the first thin film (e.g., oxide film) and the second thin film (e.g., nitride film), respectively. The measured current value tends to increase as the number of times of deposition of the thin film increases as shown in FIGS. 3 and 4. Therefore, it is desirable to reduce the current value by adjusting the process conditions, that is, the gap and the power value. At this time, in order to decrease the current value, it is possible to lower the substrate support to increase the gap or reduce the power value applied to the gas jetting body.

Before compensation (Irms, A) Gap adjustment (Irms, A) Power value adjustment (Irms, A) 1 time 8.42 8.42 8.42 Episode 2 8.52 8.43 8.24 3rd time 8.56 8.42 8.18 4 times 8.55 8.44 8.15 5 times 8.55 8.42 8.10 6 times 8.57 8.45 8.06 7 times 8.58 8.43 8.02 8 times 8.60 8.44 7.99 9 times 8.62 8.42 7.94 10 times 8.63 8.43 7.96 11 times 8.65 8.43 7.87 12 times 8.65 8.44 7.79 13 times 8.66 8.43 7.78 14 times 8.68 8.42 7.80 15 times 8.69 8.45 7.76 Deviation 0.27 0.03 0.66

As shown in Table 1, in the case where the gap adjustment or the power value is not adjusted before compensation, the current value measured increases as the deposition number of the first thin film increases, and the deviation of the current value is 0.27. However, as the current value increases, the deviation of the current value measured as a result of adjusting the distance between the substrate support and the gas jetting body, that is, the gap is reduced to about 0.03, and the initial measured current value, that is, the first thin film is deposited once The current value is adjusted to have a value substantially similar to the measured current value of 8.42A. In contrast, when the power value is adjusted, the deviation of the current value is about three times higher than that before the compensation.

Before compensation (Irms, A) Gap adjustment (Irms, A) Power value adjustment (Irms, A) 1 time 5.78 5.79 5.77 Episode 2 5.84 5.85 5.76 3rd time 5.85 5.85 5.76 4 times 5.85 5.85 5.77 5 times 5.86 5.87 5.76 6 times 5.87 5.90 5.77 7 times 5.89 5.92 5.77 8 times 5.90 5.94 5.76 9 times 5.93 5.90 5.77 10 times 5.94 5.97 5.77 11 times 5.95 5.99 5.76 12 times 5.96 6.01 5.77 13 times 5.98 6.03 5.77 14 times 6.99 6.05 5.77 15 times 6.00 6.08 5.76 Deviation 0.22 0.28 0.01

As can be seen from Table 2, in the case of adjusting the gap or controlling the power value before compensation, the current value measured gradually increases as the deposition number of the second thin film increases, and the deviation of the current value appears to be 0.22. However, it can be seen that as the current value increases, the deviation of the measured current value becomes as small as 0.01 as a result of adjusting the power value. Also, it can be seen that the adjusted current value is adjusted to have the same or substantially similar value as the measured current value 5.77 when the second thin film is deposited once. On the other hand, it can be seen that when the distance between the substrate support and the gas injector, i.e., the gap, is adjusted, the deviation of the measured current value is about 0.28, which is more than 20% higher than before the compensation.

It can be seen from the above experimental results that the process conditions for adjusting or compensating the impedance vary depending on the type of the deposited thin film. In the case of the oxide film, the impedance of the chamber can be controlled by adjusting the gap, and in the case of the nitride film, the impedance of the chamber can be controlled by adjusting the power value. Impedance can be controlled by changing the current value.

Accordingly, it is possible to suppress or prevent a decrease in uniformity of the thin film due to changes in the inside of the chamber by adjusting process conditions that compensate for environmental changes in response to environmental changes in the chamber due to the number of times of deposition depending on the type of thin film.

Such a process is repeated to prepare a database by setting the process conditions to be adjusted according to the current value measured for each type of thin film and the size thereof.

Subsequently, the substrate is placed (S112) above the substrate support inside the chamber to in-situ deposit a heterogeneous thin film on the substrate. At this time, a single substrate or a plurality of substrates S may be mounted on the substrate support.

When the substrate is loaded, the atmosphere inside the chamber and the substrate temperature are controlled (S114). A process gas is supplied into the chamber through the gas jet. Further, when the substrate S is mounted on the substrate support, the inside of the chamber is adjusted to a desired vacuum pressure, and the temperature of the substrate S is controlled by heating the substrate support. At this time, a heater is mounted inside or below the substrate support so that the substrate can be heated to an appropriate temperature.

Thereafter, various process gases are supplied to the inside of the chamber through the gas injector to expose the substrate to various gases. That is, the first raw material and the first reaction gas for depositing the first thin film into the chamber. At this time, the first raw material is a material containing an element that is a main component of the first thin film, and the first reaction gas is a gas which reacts with the first raw material to form a first thin film. The first raw material and the first reaction gas may be injected into the chamber at the same time, or one of the gases may be injected first. For example, after introducing the first reaction gas into the chamber, the first raw material may then be introduced. At this time, the first raw material may be introduced together with the carrier gas.

The process gas for forming the first thin film is introduced into the chamber and the RF power is applied to the gas jetting body while the internal pressure is maintained at a predetermined pressure. The method of using the plasma for the thin film has an advantage that the reactive gas can be easily activated even at a low temperature, and a high quality thin film can be formed by applying less energy at a high temperature.

When the process gas is introduced and the plasma is generated, the gases are converted into active species and transferred onto the substrate, so that the first raw material and the first reaction gas react with each other to form a first thin film (S122). The power and pressure are maintained for a predetermined time until the first thin film is formed to a desired thickness.

Meanwhile, before deposition of the first thin film, the current value is measured through the current meter of the matching device (S116), and the measured current value is compared with the current value stored in the database (S118) can do. However, when the first thin film is first deposited, the atmosphere inside the chamber, the impedance, and the like are set to the optimum state, so that the process conditions are rarely changed according to the current value measured through the current measuring device.

When the first thin film is deposited, the supply of the first source material and the first reaction gas is stopped (S124), and purge gas is supplied through the gas injector to remove unreacted materials and particles remaining in the chamber (S126) do.

Next, before the second thin film is deposited, a current value is measured through a current meter provided in the matching device (S126). Then, the measured current value and the current value stored in the database are compared (S128), and the process conditions are adjusted (S130). Since the impedance of the chamber may be changed in the process of depositing the first thin film, the optimal idle condition for depositing the second thin film can be made by using the measured current value.

When the process conditions for depositing the second thin film are adjusted, the second source material and the second reaction gas are supplied to the chamber through the gas injector to deposit the second thin film (S132). The process gas for forming the second thin film flows into the chamber, and RF power is applied to the gas jetting body in a state where the internal pressure is maintained at a predetermined pressure to generate plasma. When the second thin film is deposited to a desired thickness, the supply of the second source gas and the second reaction gas is stopped, and the purge gas is supplied through the gas injection body to remove unreacted materials and particles remaining in the chamber (S134).

When the first thin film and the second thin film are sequentially deposited on the substrate, the deposition is regarded as deposition once.

Thereafter, steps S116 to S134 are repeatedly performed in the predetermined number of times, and when the first thin film and the second thin film are deposited in the predetermined number of times, the substrate is taken out of the chamber (S138).

More specifically, when the first thin film is again deposited on the second thin film, the first raw material for depositing the first thin film into the chamber and the current value through the current meter before supplying the first reaction gas (S116). At this time, the measured current value and the reference current value at the time of first depositing the first thin film, that is, the current value of the database are compared with each other. If the measured current value is the same as or equal to the reference current value, The first source material and the first reaction gas for depositing the first thin film on the upper side are supplied to deposit the first thin film. Here, the error range indicates that the difference between the reference current value and the measured current value is within a predetermined range of the reference current value, for example, 0% to 5% or less. It goes without saying that the error range can be variously changed depending on the kind of the thin film to be deposited and the process conditions.

On the other hand, when the measured current value is different from the reference current value, the current value can be constantly adjusted (S120) by changing the process condition. At this time, the comparison of the current values may be performed by determining whether the measured current value is within a predetermined range with respect to the current value stored in the database. For example, when the difference between the measured current value and the reference current value is within the range of 0% to 5% of the reference current value, the thin film deposition process is performed without changing the process condition, Process conditions can be changed if the current is outside 5% of the deposition current. Such numerical values can be variously changed depending on the kind of the thin film. As described above, when the first thin film is an oxide film, the current value can be controlled constantly by controlling the gap. Therefore, the current value can be reduced by lowering the substrate support to increase the gap between the substrate support and the gas injection body.

When the current value is controlled to be constant, the first thin film is deposited (S122) by supplying the source material and the reactive gas for secondarily depositing the first thin film in the chamber through the gas jetting body.

When the first thin film is secondarily deposited on the second thin film, purge gas is supplied into the chamber to remove unreacted material and particles (S124). Further, the gap that has been increased for the adjustment of the current value is restored to its original state.

Then, the current value is measured through the current meter of the matching device (S126). At this time, if the measured current value and the current value at the time of first depositing the second thin film, that is, the reference current value are compared (S128), if the measured current value is equal to or falls within the error range, And a second source material and a second reaction gas for depositing a second thin film on the upper side are supplied to deposit the second thin film (S132).

On the other hand, when the measured current value is different from the reference current value, the current value can be stably controlled (S130) by changing the process condition. At this time, when the difference between the measured current value and the reference current value is 5% or more of the reference current value as the error range, the current value can be adjusted by adjusting the power value when the second thin film is a nitride film as described above , The current value can be reduced by reducing the power value applied to the gas jetting body.

When the current value is controlled to be constant, the source material and the reactive gas for secondarily depositing the second thin film in the chamber are supplied through the gas injector to deposit the second thin film (S132).

After the second thin film is deposited secondarily, the power value reduced for adjusting the power value is restored to its original state.

The first thin film and the second thin film may be deposited by a predetermined number of times to deposit the deposited thin film to a desired thickness (S136). When the thin film is manufactured, the thin film may be plasma treated. That is, after the thin film is manufactured, oxygen or N ₂ O plasma is generated for a predetermined time to remove unreacted bonds or particles remaining on the surface of the film, and the surface of the thin film is subjected to plasma treatment. After the plasma treatment, . When all the processes are completed, the substrate is taken out of the chamber (S138) and moved to the next process.

Hereinafter, the quality of the thin film produced will be described.

FIG. 5 is a graph comparing changes in impedance and uniformity before and after the deposition of a composite film according to an embodiment of the present invention during deposition of an oxide film, and FIG. 6 is a graph FIG. 2 is a graph comparing changes in impedance and uniformity before and after a process condition is compensated by a composite film deposition method according to the present invention. FIG.

5 (a), when the first thin film, for example, the TEOS thin film is deposited 15 times, the current value measured by the current meter provided in the matching device increases greatly as the deposition number increases, as compared with the case where the oxide film is first deposited .

In addition, the thickness and uniformity of the oxide film also vary greatly as the number of deposition increases. In particular, it can be seen that the oxide film has a uniformity of about 2.2 to 5.6%.

5 (b), in the case of adjusting the process condition, that is, the distance between the substrate support and the gas injector, the measured current value is about 10% of that of the first deposition of the oxide film The rate of change was stable. Also, it was found that the oxide film was formed to have a uniformity of about 2.1 to 2.5%, and the uniformity was improved by at least 50%.

6 (a), when the second thin film, for example, the nitride film is deposited 15 times, the current value measured by the current meter of the matching device gradually increases as the deposition number increases.

Further, the thickness and uniformity of the nitride film also vary greatly as the number of times of deposition increases. In particular, it can be seen that the nitride film has a uniformity of about 1.4 to 2.3%.

6 (b), in the case of adjusting the process condition, that is, the power value while depositing the nitride film, the measured current value has a rate of change of about 10% as compared with the case of the first deposition of the nitride film, Respectively. Further, the nitride film was formed to have a uniformity of about 1.4 to 1.7%, and it was found that the uniformity was improved by 20% or more.

Although the present invention has been described in connection with certain exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. Therefore, the scope of the present invention should not be limited by the described embodiments, but should be defined by the appended claims and equivalents thereof.

10: chamber 20: gas jet body
30: substrate support 40: pump
50: exhaust pipe 60: power supply means
62: matching device 64:

Claims (13)

A method of depositing a composite film on a substrate by alternately repeating deposition of different thin films on a substrate using plasma generated in the chamber,
A measuring step of measuring a current value for adjusting an impedance in the chamber before each thin film is deposited;
And adjusting the current value so that the current value measured in the measuring step is included in the reference setting range,
The impedance adjustment step may include:
Determining whether a current value measured in the measuring step is included within a reference setting range, adjusting a height of the substrate support in the chamber or a power value applied to a gas jetting body that injects a process gas into the chamber, Wherein the impedance of the chamber is varied by changing a process of depositing the thin film. The method according to claim 1,
Wherein the measuring step and the impedance adjusting step are repeatedly performed so that the current value measured in the measuring step is included in the reference setting range. The method of claim 2,
Wherein the different thin films are deposited in situ in the same chamber. The method of claim 3,
Wherein the composite film is formed by alternately depositing an oxide film and a nitride film. delete The method according to any one of claims 1 to 4,
The impedance adjustment step may include:
Wherein when the current value measured in the measuring step is within the reference setting range, the height of the predetermined substrate supporting portion or the power value applied to the gas jetting body is maintained. The method according to any one of claims 1 to 4,
The impedance adjustment step may include:
Wherein the thin film is an oxide film,
Wherein the height of the substrate supporting part is adjusted so that the measured current value is within a reference setting range when the current value measured in the measuring step is out of the reference setting range. The method according to any one of claims 1 to 4,
The impedance adjustment step may include:
Wherein the thin film is a nitride film,
Wherein the control unit controls the power value applied to the gas injector such that the measured current value is within the reference setting range when the measured current value is out of the reference setting range. A substrate processing apparatus for repeatedly depositing different thin films alternately in a chamber to form a composite film,
A substrate supporting unit provided inside the chamber and supporting the substrate and being driven to move up and down by the elevation driving means;
A gas spraying unit provided on the substrate support unit to supply a process gas to the substrate support unit;
A plasma generator for generating plasma in the chamber by applying plasma power to the gas injector;
A measuring unit for measuring a current value for adjusting an impedance of the inside of the chamber; And
And a controller for adjusting the measured current value so that a current value inputted from the measuring unit is included in a predetermined range before each thin film is deposited on the substrate,
The control unit determines whether or not the current value input from the measurement unit is included in the reference setting range, and adjusts the impedance of the chamber in the process of depositing the thin film according to the result, Wherein the height adjustment unit adjusts a height between the gas injection unit and the substrate support unit or adjusts a power value applied to the gas injection unit. The method of claim 9,
Wherein the oxide film and the nitride film are alternately deposited on the substrate processing apparatus. delete The method of claim 9,
Wherein,
Wherein the thin film is an oxide film,
And controls the elevation driving means to adjust the height between the gas jetting body and the substrate supporting portion such that the measured current value is within the reference setting range when the current value inputted from the measuring portion is out of the reference setting range And the substrate processing apparatus. The method of claim 9,
Wherein,
Wherein the thin film is a nitride film,
And controls the power value applied to the gas sprayer so that the measured current value is within the reference setting range when the current value inputted from the measuring unit is out of the reference setting range.

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