KR100866935B1 - Plasma processing apparatus and plasma processing method - Google Patents

Abstract

The present invention provides a plasma processing apparatus or a plasma processing method capable of etching a structure of a multilayer film for forming a gate structure with high precision and high efficiency.

To this end, the present invention uses a pressure gauge 133 and an exhaust main pump 130 used for pressure adjustment connected to the processing chamber when processing the sample on the sample stage 112 in the pressure-reduced discharge chamber 117. This is a plasma processing method for etching a multi-layer film (including high-k, metal gate) in a state of 0.1 Pa or less and the sample stage 112 at a temperature controlled state.

Description

Plasma processing apparatus and plasma processing method {PLASMA PROCESSING APPARATUS AND PLASMA PROCESSING METHOD}

1 is a cross-sectional view showing an outline of the configuration of an embodiment of a plasma processing apparatus of the present invention;

FIG. 2 is a schematic diagram showing an enlarged configuration around a sample stage of the embodiment shown in FIG. 1; FIG.

3 is a schematic diagram of a film structure for realizing a wiring structure of a semiconductor device targeted by the embodiment shown in FIG. 1;

4 is a schematic diagram of a film structure for realizing a wiring structure of a semiconductor device targeted by the embodiment shown in FIG. 1;

FIG. 5 is a graph showing the effect of a change in processing temperature on a change in pressure in a processing chamber as a condition in the case of processing the film structure shown in FIG. 3 or 4 in the plasma processing apparatus according to the embodiment shown in FIG. to be.

※ Explanation of code for main part of drawing

111: standby gate valve 112: sample stand

113: waveguide 114: magnetron

115: plate 116: shower plate

117: discharge chamber 118: buffer chamber

119 process gas line 120 shutoff valve

121: controller 122: lower ring

123: discharge chamber outer wall member 124: inner wall member

125: discharge chamber base plate 126: inner chamber

127 electrode base 128 inner lower chamber

129: flow control valve 130: main pump for exhaust

131: valve 132: piping

133: pressure gauge 134: heater

211 lower electrode 212 wafer

213: groove for refrigerant circulation 214: dielectric film

215: electrostatic adsorption DC power supply 216: high frequency power supply

217: circulating temperature controller 218: flexible tube

219: temperature control unit 220: circulation pump

221: top cover 311: Si-based

312: high-k film 313: gate film

314: gate film containing metal 315: oxide film

316: resist mask

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a plasma processing apparatus or a plasma processing method for processing a semiconductor wafer 212 using plasma to form a wiring structure of a semiconductor device, and more particularly, a semiconductor wafer 212 mounted on a sample table in a low pressure vacuum vessel. The present invention relates to a plasma processing apparatus or a processing method for etching a film structure having a film for insulating an upper and lower film as a plurality of layers for forming a wiring structure.

In recent years, high integration in semiconductor integrated circuit devices has been greatly progressed, and in MOS (Metal Oxide Semiconductor) type semiconductor devices, miniaturization and high performance of devices such as transistors have been made. In particular, as for the gate insulating film, which is one of the elements constituting the MOS structure, the thin film is rapidly progressing in order to cope with the miniaturization, high speed operation and low voltage of the transistor.

As a material constituting the gate insulating film, a silicon oxide film (SiO ₂ film) has conventionally been used. On the other hand, as the gate insulating film becomes thinner as the gate electrode becomes smaller, the tunnel current generated by the carrier (electrons and holes) directly tunnels the gate insulating film, that is, the gate leakage current increases. For example, the film thickness of the gate insulating film required for a device of a 130 nm node is about 2 nm of a SiO2 film, but this region is a region where tunnel current starts to flow. Therefore, when the SiO 2 film is used as the gate insulating film, the gate leakage current cannot be suppressed, resulting in an increase in power consumption.

Thus, research has been conducted using a material having a higher dielectric constant as the gate insulating film instead of the SiO 2 film. As an insulating film having a high dielectric constant (hereinafter referred to as a high-k film or a Hi-k film), a TiO 2 film, a Ta 2 O 5 film, and an Al 2 O 5 film have been studied. It is attracting attention because of its excellent stability.

The conditions for the treatment for treating such a high-k film are disclosed, for example, in Japanese Patent Laid-Open No. 2005-45126 (Patent Document 1). In this prior art, a film structure made of a resist pattern, an antireflection film, a silicon (polysilicon) film, a high-k film, an insulating film (SiO 2 film), or the like formed on a silicon substrate is etched using a gas containing BCl 3 and Ar. It is disclosed that the side etching of the gate silicon film is suppressed by improving the composition of the gas and the plasma density within a specific range, thereby improving the accuracy of the shape.

[Patent Document 1]

Japanese Patent Application Laid-Open No. 2005-45126

However, in the above-mentioned prior art, even if the condition for etching the multilayer film containing high-k is disclosed to improve the controllability of the shape, the condition for improving the reproducibility by performing the process stably is not sufficiently considered. Did. For example, the pressure in the processing chamber, the temperature of the sample or the sample stage, and the temperature constituting the inner wall of the processing chamber when the substrate-shaped sample such as the semiconductor wafer 212 mounted on the stage in the processing chamber disposed in the vacuum chamber is processed. Insufficient care for.

That is, in the film structure using the multilayered film for forming the fine wiring structure, for example, High-k and metal gate film, the temperature conditions at the time of processing are strict, so that the precision of the etching rate or the shape is realized if the processing is not carried out precisely while performing these processes accurately. Is lowered, resulting in impaired processing efficiency or yield. This is because the reactivity of the material of such a film is smaller than that of a silicon film (polysilicon film), which is a film for realizing a conventional gate structure. When the reactivity is increased to increase the processing speed, the temperature of the sample surface under treatment is not increased. There is no way.

On the other hand, if the sample surface is treated at a high temperature, the photoresist film as a mask disposed on the upper portion of the wiring structure becomes soft, deformed, or deteriorated, so that the function as a mask is degraded and the shape cannot be realized with high accuracy. there was. In addition, to increase the processing speed and to increase the controllability of the shape while increasing the controllability of the shape, to increase the magnitude of the high frequency power supplied to the electrode in the sample stage to form a bias potential, charging damage to the film structure being processed. There is a problem that is increased or the etching of the upper mask is increased.

In addition, the reaction product containing the compound of these materials produced during the treatment as a film structure including a film composed of a material of high melting point metal is k, the inner wall of the process chamber when the temperature of the process chamber is lower than the temperature of the sample surface It adheres and deposits on the surface of the member which comprises. The deposited product may be peeled off due to temperature change or interaction with the plasma, and may adhere to the sample surface, resulting in foreign matters. Therefore, it is necessary to suppress the adhesion of the product. In other words, it is necessary to raise the temperature of the inner wall of the processing chamber above the temperature of the sample stage. However, when the treatment is performed at a high temperature in order to improve the efficiency as described above, the structure of making the inner wall of the processing chamber higher is required. The structure is increased and the complexity of the manufacturing cost increases. In addition, when the outer surface of the vacuum container exceeds 50 ° C, facilities for safety are required, and installation of insulation materials is required, and an installation space that requires extra equipment is needed, thereby increasing the cost of installation. There was a problem.

An object of the present invention is to provide a plasma processing apparatus or a plasma processing method capable of etching a structure of a multilayer film for forming a gate structure with high precision and high efficiency. Another object is to provide a plasma processing apparatus with a simple configuration at low cost.

The object is a plasma processing method in which a sample having a layer having an upper metal film on its surface and a film of a high-k material below is disposed in a vacuum container and plasma is formed in the vacuum container to process the sample. Wherein the metal film is made of one or more materials selected from Ti, Ni, Mo, Ru, Hf, Ta, W, Re, Ri, Pt, La, Eu, Yb, and the pressure in the vacuum vessel is 0.1 Pa or less. It is achieved by a plasma processing method characterized in that the sample is treated at a temperature of 60 ° C. or lower while maintaining the temperature of the sample.
Further, the film of high-k material is achieved by the plasma processing method, characterized in that the film contains Hf.
Further, the sample is placed on the insulator film of the sample table having an insulator film made of aluminum or an alloy base material and ceramics disposed on the surface thereof, disposed in the vacuum container, and disposed by the temperature adjusting means disposed in the base material. It is achieved by a plasma treatment method characterized in that the temperature of the sample is adjusted to 60 ℃ or less.
In addition, it is achieved by a plasma processing method characterized by supplying Cl or HBr into the vacuum vessel to etch the film of the metal to form a gate structure.
In addition, a process chamber disposed in a vacuum vessel and having a plasma formed therein, and a process chamber by the plasma having a layer of an upper metal film and a lower high-k material film disposed on a lower portion of the processing chamber and on a surface thereof. A sample stage on which a sample is mounted on an upper surface, and means for heating a surface of a member facing the plasma of the processing chamber to a temperature higher than or equal to the processing temperature of the sample, wherein the film of the metal is formed of Ti, Ni, Mo, Ru, Hf, Ta, W, Re, Ri, Pt, La, Eu, Yb, and at least one material selected from the above, forming the plasma in the vacuum vessel to process the sample at a pressure of 0.1 Pa or less in the processing chamber It is achieved by a plasma processing apparatus characterized in that.
Further, it is achieved by the plasma processing apparatus, wherein the film of the high-k material is a film containing Hf.
In addition, the sample is placed on the insulator film of the sample stage having an insulator film made of aluminum or an alloy base material and ceramics disposed on the surface thereof in the vacuum container, and is disposed by the temperature control means disposed in the base material. It is achieved by a plasma processing apparatus, characterized in that the temperature of the sample is controlled to 60 ° C or less.
In addition, it is achieved by a plasma processing apparatus characterized by supplying Cl or HBr in the vacuum vessel to form a gate structure by etching the metal film.

EMBODIMENT OF THE INVENTION Hereinafter, the Example of this invention is described using drawing.

(Example 1)

The processing chamber of this embodiment will be described with reference to FIG. 1 is a longitudinal cross-sectional view schematically showing the configuration of an embodiment of a plasma processing apparatus of the present invention.

In the drawing, the plasma processing apparatus 100 includes a vacuum vessel 101, an electromagnetic wave supply means disposed above the vacuum vessel 101, and a vacuum exhaust means 107 disposed below the vacuum vessel 101. In addition, the vacuum container 101 is a substantially cylindrical space inside, a processing chamber in which a sample to be processed is disposed is disposed therein, and a vacuum conveying container 104 conveys an internal space in which a sidewall portion having a substantially rectangular plane is depressurized in a plane. )

The processing chamber in the vacuum vessel 101 is connected to the transfer chamber disposed inside the vacuum transfer vessel 104, and is opened and closed by the opening and closing means during or after the treatment as described later. That is, the communication is interrupted or interrupted by the atmospheric gate valve 111 opening and closing disposed therebetween. In the state in which the gate valve 111 is opened, the space inside the transfer chamber and the space inside the processing chamber portion communicate with each other so that the pressures are approximately equal. At the time of opening of the gate valve 111, the wafer, which is a sample, is transferred from the inside of the transfer chamber onto the sample stage 112 arranged in the processing chamber portion and mounted thereon.

The electromagnetic wave supply means disposed above the vacuum vessel 101 comprises means for supplying an electric field in the processing chamber by generating radio waves of a predetermined frequency, and means for supplying a magnetic field by generating a magnetic field by using a solenoid coil 103 or the like. Equipped. In the electric field supply means of the present embodiment, the waveguide 113 disposed in the information of the member constituting the ceiling surface of the vacuum vessel 101 and the magnetron 114 for plasma excitation are provided at the tip of the waveguide 113. The microwaves are generated by the magnetron 114 to guide the inside of the waveguide 114 toward the processing chamber. In addition, the ceiling member of the processing chamber, which is the lower end portion of the waveguide 114, includes a plate 115 made of a dielectric such as quartz and supplied under the quartz plate so as to conduct transmitted microwaves into the lower processing chamber. The shower plate 116 is provided with a plurality of holes for dividing the process gas for processing into the processing chamber.

The space formed below the shower plate 116 and above the sample chamber 112 is plasma formed by the interaction of the electromagnetic wave supplied from the magnetic field generator and the radio waves introduced through the quartz plate 115 to the supplied process gas. Discharge chamber 117 is formed. In addition, a space is formed between the quartz plate 115 and the shower plate 116 by leaving a small gap, and the process gas to be supplied to the discharge chamber 117 is first supplied to the space, and the shower plate 116 is provided. Through this space, the space communicates with the discharge chamber 117 and flows into the discharge chamber 117 through the hole through which the process gas flows. The space is a buffer chamber 118 provided so that process gas is dispersed from a plurality of holes and flows into the discharge chamber 117. This process gas is supplied from the controller 121 which regulates the supply to the process chamber of fluid, such as gas, via the process gas line 119 and the process gas shutoff valve 120. FIG.

In this way, the process gas is dispersed from the plurality of holes and introduced into the discharge chamber 117, and these holes are mainly arranged at positions opposite to the position where the sample is placed on the sample stand 112, and the gas is discharged. Along with the operation of the buffer chamber 118 that can be dispersed to be more uniform, the density of the plasma is made uniform. A lower ring 122 is disposed on the outer circumferential side of the quartz plate 115 and the shower plate 116, and a gas line 119 through which process gas flows into the buffer chamber 118 is formed inside the lower ring 122. There is a gas passage in communication with it.

Further, a lower portion of the discharge plate 116 is disposed below the shower plate 116 in contact with the lower ring 122 and the shower plate 116 at the bottom thereof, and forms a discharge chamber 117 facing the plasma inside the vacuum vessel. Wall member 123, the inner wall member 124 is disposed. In addition, in the present embodiment, the inner wall member 124 and the outer wall member 123 each have a substantially cylindrical shape and are configured to be substantially concentric. The heater 134 is wound around the outer circumferential surface of the outer wall member 123, and the temperature of the surface of the inner wall member 124 in contact with it is controlled by adjusting the temperature of the outer wall member 123. .

On the outer circumference of the outer wall member 123, a discharge chamber base plate 125 in contact with the lower surface thereof is disposed. The lower surface of the discharge chamber base plate 125 is connected to the vacuum chamber portion disposed below the discharge chamber base plate 125. In addition, the inner wall member 124 is a member that serves as a ground electrode for the plasma stage inside the discharge chamber 117 and the sample stage 112 serving as an electrode, and has an area necessary for stabilizing the potential of the plasma. have. In order to function as the ground electrode, it is necessary to sufficiently secure the conductivity together with the thermal conductivity between the outer wall member 123 or the lid member 122 which are contacted and connected.

In this embodiment, the temperature of the surface of the wall constituting the vacuum chamber is controlled to control the interaction between the surface and the plasma and the particles, gases, and reaction products contained therein. The temperature is kept higher than the temperature of the sample stage. By appropriately adjusting the interaction between the plasma and the wall surface of the vacuum chamber facing the plasma, the plasma characteristics such as the density and composition of the plasma can be brought into a desired state.

Moreover, the lower container wall 15 which comprises the lower part of a vacuum container below the discharge chamber base plate 125, the bottom part container wall 16 which connects from this lower part and forms the bottom surface of a vacuum container, and an inner lower part. An inner chamber 126 disposed in the chamber 128 and the lower surface of the discharge chamber base plate 125 and connected to the lower surface of the inner chamber 126 in contact with a lower portion of the inner chamber 126. An electrode base 127, which is a plurality of beams for supporting the 112, is disposed to form a processing chamber.

At the bottom of the bottom container wall 16, a vacuum exhaust device 107 for controlling exhaust in the vacuum container is arranged. In the present embodiment, the vacuum exhaust device 107 is disposed in the center of the inner lower chamber 128 and the bottom container wall 16 and disposed in the passage communicating with it below the opening through which the gas in the processing chamber is discharged. The main pump 130, such as a flow regulating valve 129 for adjusting the cross-sectional area of the opening by means of a plurality of plate-shaped flaps to adjust the amount of exhaust velocity, and a turbo molecular pump for exhausting gas in the processing chamber in communication with the outlet of the passage. ), And an exhaust line composed of), and a plate-shaped valve plate 131 disposed in the processing chamber and blocking the opening below.

The pressure gauge 133 used for pressure adjustment of a process chamber is arrange | positioned at the piping 132 connected to a process chamber. The exhaust main pump 130 and the pressure gauge 133 are selected to have a performance to achieve 0.1 Pa or less.

The detail of the periphery of the sample stand 112 is shown in FIG. It is a longitudinal cross-sectional view which expands and shows the outline of the structure of the sample stand periphery of the Example shown in FIG. Inside the lower electrode 211 made of a conductive member disposed inside the sample stage 112, a refrigerant for controlling temperature of the semiconductor wafer 212 to be processed by a plasma formed in the discharge chamber 117. The circulation groove 213 is disposed. The circulating temperature controller 217 for temperature adjustment is connected to the refrigerant | coolant groove 213 via the connection flexible tube 218. As shown in FIG. The circulation temperature controller 217 has a temperature controller 219 and a circulation pump 220 that are configured as a heat exchanger and a freezer for temperature adjustment.

An electrostatic adsorption dielectric film 214 is provided on the upper surface of the sample stage 112, and the semiconductor wafer 212 is connected to the lower electrode 211 using an electrostatic adsorption DC power source 215 connected to the lower electrode 211. Electrostatic adsorption is carried out to adjust the temperature. In addition, a high frequency power source 216 for controlling the reaction of the etching target material on the surface of the semiconductor wafer 212 is connected in parallel with the DC power source 215. In order to protect the surface of the lower electrode 211 other than the semiconductor wafer 212, a cover 221 is provided on the upper side.

The semiconductor wafer 212, which is a sample to be processed which is conveyed by the robot arm in the transport chamber, inside the transport chamber in the reduced pressure vacuum transport container 104, is reduced in pressure as in the transport chamber by the operation of the vacuum exhaust device 107. It is exchanged on the sample stand 112 in the processing chamber and mounted on the sample stand 112 upper surface. The mounted wafer 212 is placed on the dielectric film 214 and is held on the top surface of the dielectric film 214 by electrodes in the dielectric film 214 supplied with electric power from the electrostatic adsorption direct current power source 215.

In this state, the process gas introduced into the discharge chamber 117 causes the electric field by the microwaves propagated through the quartz plate 115 and the shower plate 116 to interact with the magnetic field supplied to the solenoid coil 103. By exciting the process gas, plasma is generated in the discharge chamber 117. The semiconductor wafer 212 on the sample stage 112 is processed using this plasma. In addition, a high frequency power of a predetermined frequency is supplied from the high frequency power supply 216 to the lower electrode 211 formed by the conductive member disposed in the sample stage 112 during processing, and the desired surface of the semiconductor wafer 212 is provided. The charged particles in the plasma are attracted to the surface of the semiconductor wafer 212 so as to cause a bias potential to promote the processing to realize a desired processing shape.

During the processing, the inner wall member 124 of the discharge chamber 117 is maintained at a predetermined temperature by the heater 134. The vacuum exhaust device 107 is also operated during the process, and discharges the process gas and plasma supplied together with the product produced by the process out of the process chamber to maintain the inside of the process chamber at a predetermined pressure value.

3 shows a film structure that serves as a wiring structure for a semiconductor device to which the plasma processing of the present invention is subjected. Fig. 3A is a schematic diagram showing the state of the film structure before processing formed on the surface of the semiconductor wafer 212 to be processed. In this figure, the film structure has a silicon substrate 311 as a lower base, and a high-k film 312 and a gate film 313 serving as a gate of the semiconductor device are arranged in this order. On the upper side is a patterned oxide film 314 that serves as a mask. The gate film 313 is composed of a single film or a composite film made of a high melting point metal material such as Ti, Ni, Mo, Ru, Hf, Ta, W, Re, Ir, Pt, La, Eu, and Yb.

Moreover, the photoresist 315 comprised from organic type materials, such as resin used as a mask at the time of processing of the oxide film 313, may be arrange | positioned above these. 4 shows the case where the material of the patterned film 315 serving as a mask is a resist mask.

In such a film structure, after the oxide film 314 is etched using the photoresist 315 as a mask, the gate film 313 disposed below the mask after the shape of the oxide film 314 is processed, and The high-k film 312 is etched. The shape after processing is shown to each (b) of FIG. 3, FIG.

FIG. 5 is a graph showing the effect of a change in processing temperature on a change in pressure in a processing chamber in the plasma processing apparatus according to the embodiment shown in FIG. 1 in the case of processing the film structure shown in FIG. 3 or 4. to be. The figure shows (1) when reacting with HBr gas when the gate material is Ta, (2) when reacting with Cl ₂ gas when the gate material is Hf, and (3) when reacting with HBr gas when the gate material is Hf. In this case, (4) the case in which the gate material is made of TaC is reacted with HBr gas.

As shown in this figure, in any of (1)-(4), when the pressure in a process chamber is 0.1 Pa or less, the temperature of the sample which volatilizes the material which comprises a film | membrane changes abruptly. That is, the temperature of the sample surface of the lower limit which can volatilize a product in predetermined | prescribed ratio is falling rapidly at 0.1 Pa or less, especially the pressure below 0.06 Pa. Especially in the case of (1), (2), and (4), it is changing rapidly to 60 degrees C or less.

When the temperature of the semiconductor wafer 212, that is, the temperature of the lower electrode exceeds 60 ° C, the linear expansion coefficient of aluminum is 2.3 × 10 ^-5 (1) when the lower electrode base material 211 is aluminum and the dielectric film 214 is alumina. / ° C.), when the linear expansion coefficient of alumina is 7.1 × 10 ⁻⁶ (1 / ° C.), and the temperature difference is 45 at the electrode temperature of 65 ° C., a dimension difference of about 0.2 mm occurs. Based on this, the stress is 1 × 10 ⁵ g / mm2, and it breaks beyond the allowable stress of 5 × 10 ⁴ g / mm. Although the structure needs to be changed, the material having a low coefficient of linear expansion deteriorates thermal response, so that temperature rise due to plasma heat input occurs.

Moreover, when processing a sample surface at 60 degreeC or more, deterioration of a resist mask becomes large, and the processing precision of the shape of the film processing of the lower side which uses this as a mask falls. In particular, in the case of a photoresist made of a hydrocarbon-based material, the deformation and softening of the photoresist increases, and when the power of the bias supplied to the electrode of the sample stage is increased to achieve a high temperature, the selectivity between the resist and the film below is lowered. Etching becomes large and the precision of processing falls.

Therefore, in the present embodiment, the conditions of the processing for suppressing the above problems are realized by maintaining the inside of the processing chamber at a pressure of 0.1 Pa or less, preferably 0.06 Pa or less to process the sample. In other words, by maintaining the pressure at the surface of the sample at 60 ° C. or lower, the reactivity of the film material can be improved and treated, and the speed of the treatment can be improved, and the degradation of the resist mask can be suppressed to improve the processing accuracy. Improvement can be achieved.

As a range of such conditions, the lower limit of pressure is 0.025 Pa, Preferably it is 0.03 Pa from the efficiency of exhaust gas, and the lower limit of the temperature which achieves the predetermined | prescribed volatilization amount at this time becomes 45 degreeC. In FIG. 5, it is the area | region upper than the line segment which connects this point of 0.025 Pa, 45 degreeC, and the point of 0.1 Pa, 60 degreeC, and can perform the said effect and effect by performing a process in the area | region below 60 degreeC.

Specifically, the temperature (T) of the sample or sample stage 112,

T = 200 P + 40

It is above the line which becomes T: temperature (degreeC) and P: pressure (Pa), and the range of T = 60 degrees C or less becomes the range of conditions suitable for a process. In the present embodiment, the degree of freedom in selection and setting of recipes for processing of samples can be increased by widening the range of pressure and temperature that can realize such processing conditions.

In this embodiment, the treatment is performed by maintaining the temperature of the sample stage 112 or the sample at a temperature of a member facing the plasma in the processing chamber such as the inner wall member 124 or the inner chamber 126 of the discharge chamber. have. At this time, as shown in this figure, by maintaining the pressure in the processing chamber at 0.1 Pa or less, the volatilization of the reaction product generated in the processing chamber becomes high, whereby foreign substances due to reattachment of the product to the surface in the processing chamber and deposition thereof are generated. This is suppressed.

By adjusting the temperature of the member disposed in the processing chamber and facing the plasma to be equal to or higher than the temperature of the surface of the processing sample placed on the sample stage, the product produced by the treatment adheres to the surface of the member inside the processing chamber. Sedimentation is suppressed. On the other hand, in this embodiment, in order to adjust the temperature of such a member in the processing chamber, a heater 134 is provided which covers and surrounds the outer wall of the discharge chamber outer wall member 123 and is in contact with the heater. Heat generated by the operation of 134 is transferred to the inside of the processing chamber to adjust the surface of the member in the processing chamber, for example, the inner wall member 124, higher than the surface of the semiconductor wafer 212 serving as the sample.

At this time, if the temperature of the sample surface exceeds a high temperature, for example, 60 ° C, it is necessary to set the temperature of the inner wall member 124 in the processing chamber to this temperature or more, and the temperature of the heater 134 becomes higher. In order to reduce the risk even when a user or an operator comes into contact with the heating part, a means for securing safety, such as covering the outer wall of the processing chamber with a heat insulating member or the like, is required, which makes the structure more complicated and requires space for installation. This increases the installation and operating costs.

In this embodiment, in the processing apparatus in which the temperature during processing of the sample is controlled to 60 ° C., preferably 50 ° C. or less, the temperature of the inner wall of the processing chamber is adjusted to be higher than this, and the temperature of the operation of the heating device is reduced. Heat insulating member and the like are unnecessary. In this case, when the pressure during the treatment of the sample is 0.1 Pa or less, preferably 0.06 Pa, more preferably 0.05 Pa or less, when treating the film structure provided with the film | membrane comprised from the metal material of the high melting point shown in FIG. The sample surface during the treatment can be treated at or below the above-mentioned temperature, and the yield of the foreign matter under treatment can be reduced by suppressing the generation of foreign matter under treatment by using a treatment apparatus having a simpler structure.

In addition, in order to realize a low pressure of 0.1 Pa or less, the distance must not be minimized in order to increase the conductance from the discharge space on the wafer to the exhaust pump. At this time, it is best to place the lower electrode in the center of the chamber as shown in Fig. 1, but it is preferable that the electrode temperature is set to 60 ° C or lower even at the heat resistance temperature of the cylinder or sensor used in the transport pushing mechanism not shown.

In the present invention, when Hf is processed, in the conventional apparatus, the use of HBr as an etching gas allows processing at a low temperature. However, by lowering the pressure, the etching with Cl2 gas can also be performed at 60 ° C or less. As a result, the selection range of the gas species for etching is increased, and the control of other processing shapes can be variously handled.

Claims (10)

A plasma processing method in which a sample having a layer having an upper metal film on its surface and a layer of a high-k material below is disposed in a vacuum container, and plasma is formed in the vacuum container to process the sample. The metal film is composed of one or more materials selected from Ti, Ni, Mo, Ru, Hf, Ta, W, Re, Ri, Pt, La, Eu, Yb, And treating the sample at a temperature of 60 ° C. or less while maintaining the pressure in the vacuum vessel at 0.1 Pa or less. The method of claim 1, And the film of high-k material is a film containing Hf. delete The method according to claim 1 or 2, The sample is placed on the insulator film of a sample stage having an insulator film made of aluminum or an alloy base material and ceramics disposed on the surface of the sample, which is disposed in the vacuum container, and the sample is disposed by the temperature adjusting means disposed in the base material. Plasma processing method, characterized in that the temperature of the control to 60 ℃ or less. The method according to claim 1 or 2, Supplying Cl or HBr into the vacuum vessel to etch the metal film to form a gate structure. A processing chamber disposed in a vacuum chamber and having a plasma formed therein; and a sample to be treated by the plasma having a layer of a metal of an upper metal and a film of a high-k material below disposed on a lower side of the processing chamber and on a surface thereof; A sample stage mounted on an upper surface, and a means for heating the surface of a member facing the plasma of the processing chamber above the processing temperature of the sample; The metal film is made of one or more materials selected from Ti, Ni, Mo, Ru, Hf, Ta, W, Re, Ri, Pt, La, Eu, and Yb, and forms the plasma in the vacuum chamber to form the plasma chamber. The sample is subjected to the treatment of the sample at a pressure of 0.1 Pa or less. The method of claim 6, And the film of high-k material is a film containing Hf. delete The method according to claim 6 or 7, The sample is placed on the insulator film of a sample stage having an insulator film made of aluminum or an alloy base material and ceramics disposed on the surface of the sample, which is disposed in the vacuum container, and the sample is disposed by the temperature adjusting means disposed in the base material. Plasma processing apparatus, characterized in that the temperature is controlled to 60 ℃ or less. The method according to claim 6 or 7, Supplying Cl or HBr into the vacuum vessel to etch the metal film to form a gate structure.

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