WO2006082717A1

WO2006082717A1 - Apparatus for forming thin film

Info

Publication number: WO2006082717A1
Application number: PCT/JP2006/300833
Authority: WO
Inventors: Tadahiro Ohmi; Kazumasa Kawase; Akinobu Teramoto
Original assignee: Tohoku University
Priority date: 2005-02-01
Filing date: 2006-01-20
Publication date: 2006-08-10
Also published as: JP2006216625A; TW200639928A

Abstract

A substrate is introduced to a treating chamber through two steps of load lock chambers and then treated. A first step load lock chamber is kept at the atmospheric pressure and the gas in the chamber is replaced by an inert gas. A second step load lock chamber has a baking heater. When a chamber having an organic material attached to the inner wall thereof is evacuated, the organic material on the inner wall is separated from the wall and the substrate is contaminated with the organic material. In the apparatus of the present invention, the substrate is subjected to evacuation in the second step load lock chamber having no organic material attached thereto, which results in the prevention of the attachment of an organic material to the substrate.

Description

Specification

Thin film forming equipment

Technical field

The present invention relates to a thin film formed on a substrate, a method for forming the thin film, a forming apparatus therefor, a semiconductor device using the thin film, and a forming method therefor.

Background art

[0002] The characteristics of semiconductor devices, liquid crystal devices, etc. are greatly affected by the composition, bonding state, impurity concentration, surface shape, etc. of the thin film's extreme surface (several nm or less). Therefore, the use of surface analysis equipment is essential.

[0003] All X-ray photoelectron spectrometers, Auger electron spectrometers, dynamic secondary ion mass spectrometers, time-of-flight secondary ion mass spectrometer analyzers, or some scanning atomic force microscopes, scanning In the type tunnel microscope, analysis or observation is performed in an ultra-high vacuum chamber, so the analysis sample is depressurized in the load-lock chamber and then transported to the analysis or observation chamber for analysis and observation.

[0004] At this time, organic contamination adhering to the inner wall of the load lock chamber is desorbed, causing a problem of contaminating the surface of the sample to be analyzed.

This is because the load lock is released to the atmosphere each time a sample is introduced, and has no mechanism for cleaning and removing organic contamination, so that organic contamination is accumulated on the inner wall of the load lock.

[0006] Fig. 4 is a graph showing the dependence of the total amount of organic substances adhering on a substrate left under atmospheric pressure and reduced pressure (Takeyuki Hayashi, "Study on Organic Contamination of Wafer Surface in Vacuum Vacuum Equipment", According to a doctoral dissertation), under reduced pressure, organic substances contaminate the substrate surface in a very short time. In the case of a surface observation device, this organic matter causes a slight increase in roughness, or obstructs the acquisition of the original surface shape. On the other hand, in the case of surface analyzers, the sensitivity is reduced by this organic matter, which hinders measurement. In addition, when analyzing carbon-containing samples or organic substances adhering to the analysis sample surface, they are disturbed by organic substances contaminated by the load lock.

[0007] For example, in the case of an X-ray photoelectron spectrometer, as shown in Fig. 1, when the surface of Si is analyzed, Peaks such as cc, co, c = o, and coo are always observed from the sample surface exposed to the atmosphere. For example, when evaluating the amount of S-to-C formation, if the peak of cc is large, reading the peak intensity of S 卜 C is hindered, so the detection sensitivity of Si-C decreases, the limit of quantification increases, Problems such as lowering of the degree occur.

[0008] For this reason, it is highly desirable to prevent organic contamination from adhering to the surface between the target treatment and measurement. As described above, when an analysis sample is transported through the load lock chamber to the analysis chamber, a reduced pressure atmosphere is inevitably generated. Therefore, organic substances are detached from the inner wall of the load lock to which organic contamination has adhered, and the sample is removed. Contaminates the surface.

On the other hand, a silicon oxide dielectric film (hereinafter referred to as silicon oxide film) which is a gate insulating film of a MOS (metal film electrode / silicon oxide dielectric film / silicon substrate) transistor has low leakage current characteristics, Various high insulation characteristics and high reliability are required, such as low interface state density, low threshold voltage shift, and low threshold variation characteristics.

[0010] Various studies and inventions have been made on the oxidation method of the silicon oxide film in order to obtain high insulation characteristics, but the surface of the silicon substrate before oxidation is required to be as clean as possible. The silicon surface is naturally oxidized in the atmosphere, and a natural oxide film is formed to a thickness of about 0.5 to 1.5 nm. However, since this oxide film has poor insulating properties, it must be etched away with a chemical solution containing HF. There is.

[0011] In order to remove metal, particles, and organic contamination, cleaning with oxidizing chemicals such as H 2 SO and 0 is performed. At this time, a chemical oxide film with poor insulating properties is formed on the silicon surface, so the above HF treatment must be performed after this step.

[0012] Further, a storage time of several minutes to several hours is required between the cleaning and the oxidation treatment. However, when HF treatment is performed, dangling bonds on the silicon surface are stabilized by termination with H atoms, and natural oxidation can be suppressed.

[0013] Although high performance of semiconductor devices has been achieved by miniaturization of elements, the thickness of the silicon oxide film must be made extremely thin. HF treatment that can remove oxide film and chemical oxide film is essential.

On the other hand, when forming a silicon oxide film by thermal oxidation, a silicon substrate at room temperature is replaced with a high-temperature acid. When inserted in a chemical furnace, there is a problem that even if the inside of the furnace is kept in a non-oxidizing atmosphere, the surrounding air is swallowed and an oxide film starts to form at a temperature lower than the original processing temperature.

[0015] In order to prevent this, a load lock chamber is provided as the front chamber of the furnace, and oxygen or moisture concentration is reduced by an inert gas such as N or Ar or a non-oxidizing atmosphere such as vacuum. Therefore, the substrate may be introduced into the furnace and heated in a non-oxidizing gas atmosphere. However, if both HF treatment and non-oxidizing atmosphere temperature rise are used, there is a problem that the insulating properties of the silicon oxide film deteriorate.

[0016] When H, which terminates the silicon surface, desorbs at a temperature of 430 ° C or higher, a dangling bond is formed. However, if organic contamination exists on the silicon surface, the silicon dangling bond and organic contamination This is because it reacts to form SiC.

[0017] In the case of processes below 430 ° C, such as radical acid, plasma oxidation, etc., if H is incorporated into the film, it will adversely affect the insulation characteristics. Therefore, H is removed by irradiation with rare gas ions. It is necessary to perform processing afterwards. In this case, dangling bonds are also formed. However, if organic contamination exists on the silicon surface, the dangling bonds on the silicon surface react with the organic contamination to form SiC, which degrades the insulation characteristics.

[0018] Figure 1 (a) shows the XPS Cls core-level photoelectron spectrum of the surface of the substrate after HF treatment heated to 800 ° C in Ar gas, a non-oxidizing atmosphere, and is related to the Si-C bond. The observed peak is clearly observed. When the temperature is raised in 0, which is an oxidizing atmosphere, and when the temperature of the SiO surface (substrate without HF treatment) is raised in Ar gas, as shown in Figs. 1 (b) and 1 (c), No SiC peak is observed. The C-C, C-O, C = 0, and COO peaks detected from the main peak to the high binding energy side are peaks related to organic substances contaminated from the atmosphere after the oxidation treatment and before measurement.

[0019] Figure 2 shows the temperature dependence of the amount of SiC formed when the substrate after HF treatment is heated in vacuum, and the desorption temperature characteristics of terminal H. From this result, the formation mechanism of SiC is shown by the reaction model in Fig. 3.

[0020] As shown in Fig. 3 (a), the Si (100) surface after HF treatment has a structure in which Si atoms on the resurface are terminated with H in two of the four bonds. Yes. From 300 to 430 ° C, one of the H ends of the two bonds is desorbed, and Si forms a dangling bond. A dimer is formed by combining with a ring bond, and the structure changes as shown in Fig. 3 (b).

[0021] From 430 to 600 ° C, the remaining H also desorbs to form a dangling bond, but cannot be bonded because the distance from the adjacent dangling bond is too large. As shown in (2), it becomes a very active surface covered with dangling bonds. On the other hand, with organic contamination, part of the molecular structure decomposes and partly desorbs when the temperature rises, but some remains on the surface. Since these have dangling bonds, they easily combine with dangling bonds on the Si surface to form SiC.

[0022] It is not easy to completely prevent organic contamination from adhering to the substrate and to suppress the formation of SiC. For this reason, conventionally, the temperature is raised in a non-oxidizing gas atmosphere containing an oxidizing gas such as 0 to several tens of percent, and an oxide film is formed at a low temperature (hereinafter referred to as a low temperature oxide film). A process for carrying out the oxidation is generally used. Insulation characteristics of low-temperature oxide films are better than natural oxide films, chemical oxide films, entangled oxide films, etc., but they are worse than oxide films formed at high temperatures. Improvement can be expected.

[0023] Once contaminated, organic contamination is extremely difficult to remove without oxidizing or nitriding the surface of the Si substrate and without sacrificing surface flatness. Oxidizing gases such as 0, H 0, N 0 and NO, nitriding gases such as NH, N 0 and NO, noble gases such as Kr, Xe and Ar, inert gases such as N, reduction of H and the like It is impossible to irradiate with a reactive gas, or plasma irradiation or ion irradiation.

[0024] For this reason, in order to realize an Si surface that excludes all of the uncontrolled oxide film, SiC, and H, and to form an oxide film that does not include all of these, organic contamination is caused on the substrate surface. It is essential to develop a method to prevent adhesion. Here, these oxide films with poorer insulation properties than the oxide films formed by this oxidation, such as natural oxide films, chemical oxide films, entrained oxide films, and low-temperature oxide films, are called uncontrolled oxide films.

Disclosure of the invention

Problems to be solved by the invention

[0025] In order to prevent organic contamination from adhering to the substrate surface, the cleaning chemical solution, the atmosphere in the cleaning device, the clean norm atmosphere, the atmosphere in the transfer container, the atmosphere in the load lock chamber, the atmosphere in the oxidation treatment chamber, the process gas, etc. It is necessary to remove organic matter, but all parts It is very difficult to completely prevent organic contamination because organic substances are used in

[0026] In order to completely remove organic pollution from the entire clean room atmosphere, a huge amount of air must be removed by a chemical filter. It is practical to clean or clean the substrate transfer container.

[0027] Organic contamination in the cleaning chemical and process gas is already suppressed to a low level. Also

By using a high purity inert gas near atmospheric pressure, it is possible to prevent organic contamination in the atmosphere inside the cleaning device and the atmosphere inside the transfer container.

[0028] However, the atmosphere in the load lock chamber and the atmosphere in the oxidation treatment chamber must be depressurized and introduced with high-purity inert gas or process gas in order to prevent the surrounding atmosphere from being involved. Is common.

[0029] If the pressure is reduced while the organic pollutant adheres to the inner wall due to contact with the clean noreme atmosphere or diffusion from the knock pump, the organic pollutant adhering to the inner wall is detached from the inner wall, and a part of it is deposited on the substrate surface. Adhere to.

[0030] Fig. 4 is a graph showing the dependence of the total amount of organic substances adhering to the substrate left under atmospheric pressure and reduced pressure on the duration of release.

[0031] Under reduced pressure, organic matter is contaminated in a very short time. However, the oxidation chamber is not opened to the atmosphere except during maintenance, and the organic contamination is burned and removed every time the oxidation treatment is performed. Therefore, the organic contamination is not removed when the gate vano lev between the load lock chamber and the chamber is opened. However, it can only flow from the load-lock chamber or be brought back-spread from the back pump between the previous process and the next process.

[0032] The amount of these contaminating the oxidation processing chamber walls and desorbing during depressurization to contaminate the substrate is small compared to that in the load-lock chamber that is opened to the atmosphere and organic substances are not removed by oxidation or the like. It is the load lock chamber that is most likely to contaminate the substrate with organic substances, and improvement of this part is the most important.

[0033] Although the case of oxidation treatment has been described above as an example, the formation of SiC adversely affects the characteristics of the thin film even in the case of a thin film forming apparatus such as CVD. In addition, the state of organic matter without forming SiC Even in this state, if it adheres to the substrate, it may affect the characteristics of the thin film. Therefore, preventing general organic contamination from adhering to the substrate is also an important issue for general thin film forming equipment.

[0034] The present invention has been made to solve the above-mentioned problems, and its purpose is to suppress the adhesion of organic contamination to the substrate, thereby preventing uncontrolled oxide film free, organic contamination free, Si The aim is to provide thin films such as silicon oxide films that are C-free, H-free, and flat at the atomic level.

[0035] Another object of the present invention is to suppress contamination of organic substances on the surface of an analysis sample by using a two-stage load lock.

Means for solving the problem

[0036] In order to achieve the above object, the thin film forming apparatus of the present invention accommodates a first stage load lock chamber in which a substrate is introduced from the outside and replaced with an inert gas while maintaining atmospheric pressure, and the substrate. And a second stage load lock chamber equipped with a mechanism that does not adsorb organic substances on the inner wall, or a mechanism for removing adsorbed organic substances, and a film formation mechanism for accommodating a substrate and forming a predetermined thin film. A gas atmosphere control unit for controlling the vacuum level and gas concentration of the processing chamber, the first stage load lock chamber, the second stage load lock chamber and the processing chamber to predetermined values, the first stage load lock chamber, A transfer mechanism that moves the substrate between the second-stage load lock chamber and the processing chamber, the first-stage load lock chamber and the second-stage load lock chamber, and the second-stage load lock chamber and the processing chamber, respectively. With a gate vanolev for opening and closing and passing through the substrate It is characterized by that.

[0037] Preferably, the gas atmosphere control unit includes an exhaust unit for exhausting the first-stage load lock chamber, the second-stage load lock chamber, and the processing chamber, and an exhaust amount control gate valve for controlling an exhaust amount. And a gas introduction part for introducing gas, and a gas flow control valve for controlling the gas flow rate.

[0038] It is preferable that the second-stage load lock chamber has a cleaning mechanism for detaching organic substances attached to the inner wall of the furnace or preventing the attachment of organic substances.

[0039] The cleaning mechanism has, for example, a heating mechanism for baking the inner wall.

[0040] The cleaning mechanism includes, for example, a plasma generation mechanism that irradiates plasma on the inner wall. [0041] The thin film formation mechanism includes, for example, a plasma generation unit for performing radical oxidation and an oxidizing gas introduction unit.

[0042] The thin film formation mechanism includes, for example, a plasma generation unit for performing radical nitriding and a nitriding gas introduction unit.

[0043] The thin film formation mechanism includes, for example, a plasma generation unit for performing radical oxynitridation, and an introduction unit of an oxynitriding gas or an oxidizing gas and a nitriding gas.

[0044] The thin film forming mechanism includes, for example, a heating unit for performing thermal oxidation and an oxidizing gas introduction unit.

The thin film formation mechanism includes, for example, a heating unit for performing thermal nitridation and a nitriding gas introduction unit.

[0046] The thin film forming mechanism includes, for example, a heating unit for performing thermal oxynitridation, and an introduction unit for an oxynitriding gas or an oxidizing gas and a nitriding gas.

[0047] The thin film formation mechanism includes, for example, a heating unit for performing CVD film formation and a source gas introduction unit.

[0048] The thin film formation mechanism includes, for example, a target for performing sputter film formation, and an ion generation unit.

And a heating part and a raw material gas introduction part.

[0049] The plasma generation unit for performing the radical oxidation, radical nitridation, and radical oxynitridation preferably includes a microwave generation unit, a microwave waveguide, and a radial line slot antenna.

[0050] It is preferable that the plasma generation unit for performing the radical oxidation, radical nitridation, and radical oxynitridation includes parallel plate electrodes to which a high frequency can be applied.

[0051] Preferably, the CVD film formation includes a group consisting of SiO 2, SiN, SiON, HfO, HfSiO, and HfSiON.

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Forming at least one thin film for a gate insulating film selected from the group.

[0052] Preferably, the sputter film formation is a film formation of a base thin film for forming a gate insulating film of S or Hf.

[0053] In addition, a transport container that is transported in an inert atmosphere at atmospheric pressure from at least a pretreatment device that performs a cleaning process includes a second-stage load port chamber that prevents adhesion of organic substances or removes organic substances. Connected via a gate valve, the second stage load locks the substrate without touching the atmosphere. It has a mechanism that can be introduced into the chamber, and this transfer container may serve as a first-stage load lock chamber that creates an inert gas atmosphere at atmospheric pressure.

[0054] Alternatively, at least the processing chamber of the pretreatment apparatus that performs the cleaning process or its load lock chamber is connected directly to the load lock chamber force S, which prevents organic substances from adhering to or removes organic substances, via a goat valve. In addition, the processing chamber of this pretreatment device or its load lock chamber may serve as a first-stage load lock chamber that maintains an inert gas atmosphere at atmospheric pressure.

[0055] Thus, in the present invention, in order to reduce the adhesion of organic contamination to the substrate, a two-stage load port chamber is used, and the first-stage load lock chamber is an inert gas at atmospheric pressure. The second-stage load lock chamber has a mechanism that prevents organic substances from adhering to the inner wall, keeps it clean, and reduces the pressure of the impurity gas before introducing the substrate into the processing chamber.

[0056] Since the first stage load lock chamber is opened to the atmosphere when the substrate is introduced, organic contamination adheres to the inner wall of the substrate, but it is replaced by an inert gas without reducing the pressure. Organic contamination can be prevented. However, the impurity gas concentration in the first-stage load lock chamber can only be lowered to a higher level than when the pressure is reduced.

[0057] Next, the substrate is introduced into the second-stage load lock chamber. The second-stage load lock chamber has a mechanism that prevents organic substances from adhering to the inner wall or a mechanism that can remove organic substances.

For example, this can be realized by always baking the inner wall or by providing a mechanism for generating plasma of a gas not containing C, such as an oxidizing gas, a hydrogen gas, and a nitriding gas.

[0059] When a substrate is introduced from the first-stage load lock chamber into the second-stage load lock chamber, there is no organic contamination, but there is a small amount of impurity gas. To prevent this impurity gas from being brought into the processing chamber, the second-stage load lock chamber is depressurized, but the inner wall of the second-stage load lock chamber is free of organic contamination. Will not be organically polluted

If the substrate is introduced into the processing chamber after doing in this way, it is possible to prevent both organic contamination of the substrate surface and the introduction of impurity gas into the processing chamber. If the pressure in the first-stage load lock chamber is 100 Torr or higher, the adhesion of organic contamination is almost negligible, but even higher than atmospheric pressure is better. [0061] The above assumes that the substrate exposed to the atmosphere is transported, but the substrate is transported in a container filled with an inert gas free from organic contamination, and the load lock chamber is opened to the atmosphere. If the mechanism allows the board to be introduced into the load lock chamber, the first load load chamber can be omitted. In other words, it plays the role of the load lock chamber at the si stage of the transfer container force.

[0062] In addition, when the cleaning apparatus and the thin film forming apparatus are physically connected and transported through a transfer chamber free from organic contamination, the load lock chamber is not necessary. Since it is not open to the atmosphere, the first-stage load lock chamber is unnecessary. In addition, a second load lock chamber is not required to provide a mechanism in the transfer chamber that prevents organic matter from adhering to the inner wall.

[0063] However, in the present situation where cleaning is performed in a batch process, or in the present situation where a cleaning apparatus and various thin film forming apparatuses are separately developed, this method has a problem in terms of cost, and thus the present invention. There is an advantage in the form of.

[0064] If the impurity gas is brought into the processing chamber without affecting the accuracy of the process and it is not necessary to keep the processing chamber at a reduced pressure, the second-stage load lock chamber may be omitted. it can. In other words, the processing chamber plays the role of the second-stage load lock chamber.

However, at the present time when thin films used in semiconductor devices have become extremely thin, the process gas atmosphere is increasingly required to be highly purified, and the demand for the form of the present invention is high.

[0066] As described above, by preventing organic contamination from the inner wall of the load lock chamber to the substrate, formation of SiC and incorporation of organic substances into the film and film / substrate interface are prevented.

In the present invention, the two-stage load lock is used as a load lock chamber of a surface analyzer or a surface observation device, thereby preventing organic substances from adhering to the analysis sample surface.

The invention's effect

[0068] According to the present invention, it is possible to prevent organic contamination from adhering to the silicon substrate at low cost while maintaining the purity of the process gas atmosphere. For this reason, SiC is not formed even if H that terminates the silicon surface is removed immediately before the oxidation treatment. This makes it possible to form only a high-quality oxide film on the silicon surface of uncontrolled oxide film free, organic contamination-free, SiC-free, and H-free, thereby improving the insulation characteristics.

[0069] By preventing organic contamination from adhering to the silicon substrate even in cases other than oxidation treatment, Incorporation of organic substances into the film / substrate interface in the film is prevented, and a high-quality thin film can be formed. As a result, silicon oxide films and other thin films can be made thinner than they are currently, and high performance of VLSI can be realized.

Brief Description of Drawings

[0070] [Fig. 1] (a) shows the surface of the substrate after HF treatment heated to 800 ° C in Ar gas, and (b) shows the temperature of the substrate after HF treatment raised to 800 ° C in 0 gas. (C) shows SiO formed on the surface without HF treatment

twenty two

This figure shows the XPS Cls core-level photoelectron spectrum of the surface of the resulting substrate heated to 800 ° C in Ar gas.

[Fig. 2] A graph showing the temperature dependence of the amount of SiC formed and the desorption temperature characteristics of terminal H when the substrate after HF treatment is heated in vacuum.

[Fig. 3] (a) to (c) are model diagrams showing how the Si (lOO) surface after HF treatment desorbs H and restructures to form SiC as the temperature rises.

[FIG. 4] A graph showing the dependence of the total amount of organic substances adhering to a substrate left in a reduced-pressure atmosphere and atmospheric pressure on the standing time.

FIG. 5 is a diagram showing an example of a thin film forming apparatus (radial power oxidizer) that prevents adhesion of organic substances shown in Embodiment 1 of the present invention.

FIG. 6 is a diagram showing an example of a thin film forming apparatus (radial power oxidizing apparatus) that prevents the adhesion of organic substances shown in the second embodiment of the present invention.

FIG. 7 is a diagram showing an example of a surface analysis device or a surface inspection device shown in the third embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

[0071] (Embodiment 1)

A dielectric film forming apparatus according to Embodiment 1 of the present invention will be described.

As shown in FIG. 5, a first-stage load lock chamber 10 and a second-stage load lock chamber 11 are provided in the front chamber of the processing chamber 12. The two load lock chambers 10, 11 and processing chamber 12 have gas inlet ports 30, 31, 32, gas flow control valves 53, 54, 55, exhaust pumps 13, 14, 15, and exhaust volume control gate valves, respectively. 43, 44, 45, the gas flow rate control valve 53, 54, 55 and the displacement control valve 43, 44, 45 to control the degree of vacuum and gas concentration to control the gas atmosphere control unit 50, 51 and 52.

[0073] Between the first-stage load lock chamber 10 and the outside, between the first-stage load lock chamber 10 and the second-stage load lock chamber 11, and between the second-stage load lock chamber 11 and the processing chamber 12. Gate valves 40, 41, and 42 are installed, respectively. The second-stage load lock chamber 11 is equipped with a baking heater 20 to prevent organic substances from adhering to the inner wall. In the processing chamber 12, the RLSA antenna 21, waveguide 22, and microwave generator 23 necessary for radical oxidation are installed.

[0074] After introducing an inert gas into the first-stage load lock chamber 10 and bringing it to atmospheric pressure, the gate valve 40 is opened to release the atmosphere, and the first-stage load lock chamber 10 is processed from the outside to the first-stage load lock chamber 10 Substrate 1 is introduced, and gate vano lev 40 is closed. At this time, the organic substance 5 slightly enters from the outside air, but the organic substance 5 accumulates on the inner wall of the load lock chamber 10 in the first stage because it is released to the atmosphere for each treatment. The substrate 1 to be processed is supported on the transfer stage 2. In the first-stage load lock chamber 10, an inert gas such as N is introduced from the gas inlet 30, and the force S exhausted by the exhaust pump 13, the gas flow control valve 53 and the exhaust control gate valve 43 are opened and closed. By adjusting the gas atmosphere control unit 50, it is replaced with N while maintaining the atmospheric pressure. Load lock room

Since 10 is not depressurized, the organic substance 5 does not desorb from the inner wall of the load lock chamber 10, and the substrate 1 is not contaminated with the organic substance 5.

On the other hand, the load lock chamber 11 in the second stage is evacuated in a steady state and heated by the baking heater 20 so that the organic substance 5 does not adhere to the inner wall. After introducing an inert gas into the second-stage load lock chamber 11 and bringing it to atmospheric pressure, the gate valve 41 is opened, the substrate 1 is moved onto the transfer stage 3, and the gate vano rev 41 is closed. At this time, since a small amount of impurity gas in the first-stage load lock chamber 10 partially flows into the second-stage load lock chamber 11, the second-stage load lock chamber 11 is once evacuated and then discharged. Purge with active gas. By several evacuations and inert gas purges, the impurity concentration is sufficiently reduced. Since organic substance 5 does not adhere to the inner wall of load lock chamber 11 in the second stage, organic substance 5 does not contaminate substrate 1 even under reduced pressure.

[0076] Here, the baking heater 20 was used to prevent the organic matter 5 from adhering to the inner wall, but the adhering organic contamination was detected by using a gas that does not contain C, such as oxygen plasma, hydrogen plasma, and nitrogen plasma. A method of cleaning the inner wall by generating the generated plasma is also effective. [0077] The processing chamber 12 is evacuated in a steady state. If no treatment has been performed immediately before, there is a small amount of organic matter adhering to the inner wall due to reverse diffusion from the exhaust pump 15, so a dummy substrate is inserted and the inner wall is then treated with oxygen plasma, hydrogen plasma, or nitrogen plasma. It is preferable to clean. In the case of a thermal oxidation furnace, the organic matter 5 should be burned and removed by thermal oxidation. Even in the case of a CVD furnace, remove organic matter 5 by raising the temperature by flowing an oxidizing gas.

[0078] After the second-stage load lock chamber 11 and the processing chamber 12 have the same degree of vacuum of about 1 Kpa, the gate valve 42 is opened, the substrate 1 is moved to the processing stage 4, and the gate valve 42 is closed. After the processing stage 4 is heated to the process temperature, plasma is generated from the microwave generator 23 through the waveguide 22 and directly under the na 21. This plasma generates a Kr gas plasma, supplies Kr radicals and Kr ions to the surface of the substrate 1, and removes the H that terminates the surface of the substrate 1. After that, the substrate 1 is oxidized by oxygen radicals generated by Kr / O etc.

2

To do.

[0079] Here we show the example of Kr / O radical oxidation using RLAS.

2

The same applies to radical oxidation by plasma generated by the method, and when inert gases such as Xe and Ar other than Kr are used. The same applies to thermal oxidation, CVD oxide film formation, radical nitridation, thermal nitridation, radical oxynitridation, thermal oxynitridation, sputtering, and other thin film formations. What is important is that the two-stage load lock chambers 10 and 11 keep the organic material 5, SiC, and other H and uncontrolled oxide films on the surface of the substrate 1 immediately before processing.

[0080] (Embodiment 2)

A thin film forming apparatus according to Embodiment 2 of the present invention will be described.

As shown in FIG. 6, a first-stage load lock chamber 10 and a second-stage load lock chamber 11 are provided in the front chamber of the processing chamber 12. The load lock chamber 11 and the processing chamber 12 in the second stage have gas inlets 31 and 32, gas flow control valves 54 and 55, exhaust pumps 14 and 15, displacement control gate valves 44 and 45, respectively, Gas flow control valves 54 and 55 and exhaust gas control valves 44 and 45 are provided to control the degree of vacuum and gas concentration, and gas atmosphere control units 51 and 52 are provided. [0082] Between the first stage load lock chamber 10 and the outside, between the outside and the second stage load lock chamber 11, and between the second stage load lock chamber 11 and the processing chamber 12, gate valves 46, 40 and 42 are installed. The second-stage load lock chamber 11 is equipped with a baking heater 20 to prevent organic substances from adhering to the inner wall. In the processing chamber 12, a radial line slot antenna (RLSA antenna) 21, a waveguide 22, and a microwave generator 23 necessary for radical oxidation are installed.

[0083] The first-stage load lock chamber 10 is purged with an inert gas, for example, by another pretreatment device such as a cleaning device, and is used as a transfer container for transfer to the thin film forming apparatus. The first-stage load lock chamber 10 is connected to the second-stage load lock chamber 11, and the substrate 1 is moved from the first-stage load lock chamber 10 to the second-stage by opening the gate valve 46 and the gate valve 40. It has a mechanism that can transport it to the load lock chamber 11.

[0084] The first-stage load lock chamber 10 is brought to atmospheric pressure by introducing an inert gas from another device. On the other hand, the load lock chamber 11 in the second stage is evacuated during normal operation and heated by the baking heater 20 so that organic substances do not adhere to the inner wall. An inert gas is introduced into the second-stage load lock chamber 11 to bring it to atmospheric pressure, and after the first-stage load lock chamber 10 and the second-stage load lock chamber 11 are connected, the gate valve 46 and the gate valve 40 are connected. The substrate 1 to be processed is introduced into the load lock chamber 11 in the second stage, and the gate valve 46 and the gate valve 40 are closed.

[0085] At this time, there is no contamination of organic matter on the inner wall of the second load lock chamber 11 where outside air does not enter. However, since a small amount of impurity gas in the first-stage load lock chamber 10 partially flows into the second-stage port lock chamber 11, the second-stage load lock chamber 11 is once evacuated and then inactive. Purge with gas. Impurities are sufficiently reduced by several evacuations and inert gas purges. Since organic substances do not adhere to the inner wall of the second-stage load lock chamber 11, the organic substances do not contaminate the substrate 1 even under reduced pressure. The substrate 1 to be processed is supported on the transfer stage 3.

[0086] Here, the baking heater 20 was used to prevent the organic matter from adhering to the inner wall, but the adhering organic contamination was generated by generating plasma using a gas containing no C, such as oxygen plasma and nitrogen plasma. The method of cleaning the inner wall is also effective. [0087] The processing chamber 12 is evacuated in a steady state. If no treatment has been performed immediately before, there is a small amount of organic matter adhering to the inner wall due to back-diffusion from the exhaust pump 15, so a dummy substrate is inserted and the inner wall is cleaned with oxygen plasma or nitrogen plasma. It is preferable to keep it. In the case of a thermal oxidation furnace, it is better to burn off organic substances by thermal oxidation. Even in the case of a CVD furnace, the organic substances are removed by flowing an oxidizing gas and raising the temperature.

[0088] After the second-stage load lock chamber 11 and the processing chamber 12 have the same degree of vacuum of about 1 KPa, the gate valve 42 is opened, the substrate 1 is moved to the processing stage 4, and the gate valve 42 is closed. After the processing stage 4 is heated to the process temperature, plasma is generated from the microwave generator 23 through the waveguide 22 and directly under the na 21. This plasma generates a Kr gas plasma, supplies Kr radicals and ions to the surface of the substrate 1, and removes the H that terminates the surface of the substrate 1. After that, the substrate 1 is oxidized by oxygen radicals generated by Kr / O.

[0089] Here we show examples of Kr / O radical oxidation using RLAS. Parallel plates, radical oxidation by plasma generated by other methods, and inert gases such as Xe and Ar other than Kr. The same applies to the case of using. The same applies to thermal oxidation, CVD oxide film deposition, radical nitridation, thermal nitridation, radical oxynitridation, thermal oxynitridation, and other thin film depositions. What is important is that the two-stage load lock chambers 10 and 11 make the surface of the substrate 1 just before the treatment have no organic substances, SiC, other H, and uncontrolled oxide films.

[0090] (Embodiment 3)

A surface analysis apparatus or surface inspection apparatus according to Embodiment 3 of the present invention will be described.

As shown in FIG. 7, a first-stage load lock chamber 10 and a second-stage load lock chamber 11 are provided in the front chamber of the processing chamber (analysis chamber or observation chamber) 12. The two load lock chambers 10, 11 and the processing chamber 12 have gas inlets 30, 31, 32, gas flow control valves 53, 54, 55, exhaust pumps 13, 14, 15, and exhaust volume control gate valves, respectively. 43, 44, 45 and the gas flow control valve 5 3, 54, 55 and displacement control valves 43, 44, 45 to control the degree of vacuum and gas concentration, and gas atmosphere control units 50, 51, 52 are provided.

[0092] Between the first-stage load lock chamber 10 and the outside, between the first-stage load lock chamber 10 and the second-stage load lock chamber 11, and between the second-stage load lock chamber 11 and the processing chamber 12. Gate valves 40, 41, and 42 are installed, respectively. The second-stage load lock chamber 11 is equipped with a baking heater 20 to prevent organic substances from adhering to the inner wall. The processing chamber 12 is equipped with an X-ray source (excitation source) 24 and a detector 25 necessary for analysis and observation.

[0093] After introducing an inert gas into the first-stage load lock chamber 10 and bringing it to atmospheric pressure, the gate valve 40 is opened to release the atmosphere, and analysis or observation is performed from outside the apparatus to the first-stage load lock chamber 10. The substrate 1 is introduced and the gate valve 40 is closed. At this time, the organic substance 5 has accumulated on the inner wall of the load lock chamber 10 at the first stage because the force S that organics enter slightly from the outside air and the first stage load lock chamber 10 is released to the atmosphere for each treatment. The substrate 1 to be processed is supported on the transfer stage 2. In the first-stage load lock chamber 10, an inert gas such as N is introduced from the gas inlet 30 and exhausted by the exhaust pump 13, but the gas flow control valve 53 and the exhaust control gate valve 43 are opened and closed. Is adjusted to N while maintaining the atmospheric pressure by adjusting the gas atmosphere control unit 50. Since the port lock chamber 10 is not depressurized, the organic material 5 does not desorb the inner wall force of the load lock chamber 10, and the substrate 1 is not contaminated by the organic material 5.

On the other hand, the load lock chamber 11 in the second stage is evacuated in a steady state and heated by the baking heater 20 so that organic substances do not adhere to the inner wall. After introducing an inert gas into the second-stage port lock chamber 11 to bring it to atmospheric pressure, the gate valve 41 is opened, the substrate 1 is moved onto the transfer stage 3, and the gate vano rev 41 is closed. At this time, a small amount of impurity gas in the first-stage load lock chamber 10 flows into the second-stage load lock chamber 11, so the second-stage load lock chamber 11 must be evacuated. If the processing chamber 12 is ultra-high vacuum, the load lock chamber is evacuated to at least high vacuum. Since organic substances do not adhere to the inner wall of the second-stage load lock chamber 11, the organic substances do not contaminate the analytical sample even under reduced pressure.

[0095] Here, in order to prevent organic matter from adhering to the inner wall, force using the baking heater 20 was used. Organic gas that did not contain C, such as oxygen plasma and nitrogen plasma, was used as the attached organic contamination. A method of generating plasma and cleaning the inner wall is also effective.

[0096] The processing chamber 12 is evacuated to an ultra-high vacuum by an ion pump or the like in a steady state. In order to achieve an ultra-high vacuum, the inner wall of the analysis chamber has already been cleaned by baking.

[0097] After raising the second-stage load lock chamber 11 to a degree of vacuum higher than high vacuum, the gate valve 42 is opened, the analysis sample 1 is moved to the processing stage 4, and the gate valve 42 is closed. Analysis or observation is performed by irradiating the sample surface with X-rays, electron beams, ion beams, or bringing a probe closer. Figure 7 shows an example of an X-ray photoelectron spectrometer. The X-ray source 24 irradiates the surface of the analysis sample with X-rays, and the photoelectrons jumping out of the analysis sample are detected by the detector 25 including the energy spectrometer. What is important is that the two-stage load lock chamber 11 ensures that no organic matter exists on the substrate surface immediately before analysis.

Industrial applicability

According to the present invention, it is possible to prevent organic contamination from adhering to the substrate surface and form a thin film free from organic contamination. In the case of radical oxidation, the insulation characteristics of the silicon oxide film are improved by simultaneously preventing the formation of an uncontrolled oxide film, the adhesion of organic contamination, the formation of SiC, and the incorporation of H into the silicon oxide film. As a result, the present invention can be applied to a VLSI capable of realizing thinning of a silicon oxide film and high reliability of other thin films and high performance.

Claims

The scope of the claims

[1] A first-stage load lock chamber that can be installed by introducing a predetermined sample from the outside and can be replaced with an inert gas while maintaining 10 kPa to 1000 kPa,

A two-stage load-lock chamber characterized by having a second-stage load-lock chamber that houses a specified sample and does not adsorb organic substances on the inner wall, or has a mechanism that can remove adsorbed organic substances.

[2] The load analyzer according to claim 1, wherein the load lock chamber is used for a surface analyzer.

Two-stage load lock room.

[3] The device according to claim 1, which is used as a load lock chamber of a surface observation device.

Two-stage load lock room.

[4] The surface analyzer is an X-ray photoelectron spectrometer, an Auger electron spectrometer, dynamic

3. The two-stage load lock according to claim 1, which is a secondary ion mass spectrometer, a time-of-flight secondary ion mass spectrometer, a scanning interatomic microscope, or a scanning tunneling microscope. Room.

[5] A substrate is introduced from the outside, and the atmospheric pressure is lOKpa ~:! First stage load-lock chamber that is replaced with inert gas while maintaining OOOKpa;

A second stage load lock chamber equipped with a mechanism for accommodating the substrate and not adsorbing or removing adsorbed organic matter on the inner wall;

A processing chamber having a film forming mechanism for accommodating a substrate and forming a predetermined thin film;

A gas atmosphere control unit for controlling the vacuum degree and gas concentration of the first-stage load lock chamber, the second-stage load lock chamber, and the processing chamber to respective predetermined values;

A transport mechanism for moving the substrate between the first-stage load lock chamber, the second-stage load lock chamber, and the processing chamber;

A thin film forming apparatus comprising: a first stage load, a lock chamber and a second stage load, a lock chamber, a second stage load, and a gate vano lev for opening and closing the lock chamber and the processing chamber.

[6] The gas atmosphere control unit includes an exhaust unit for exhausting the first-stage load lock chamber, the second-stage load lock chamber, and the processing chamber, and an exhaust amount control gate valve for controlling the exhaust amount. 6. The thin film forming apparatus according to claim 5, further comprising: a gas introduction unit for introducing gas; and a gas flow rate control valve for controlling a gas flow rate.

[7] The second stage load lock chamber has a cleaning mechanism for removing organic substances adhering to the inner wall of the furnace or preventing adhesion of organic substances. 6. The thin film forming apparatus according to 6.

8. The thin film forming apparatus according to claim 7, wherein the cleaning mechanism has a heating mechanism for baking the inner wall.

9. The thin film forming apparatus according to claim 7, wherein the cleaning mechanism has a plasma generation mechanism for irradiating plasma on an inner wall.

10. The thin film forming apparatus according to any one of claims 5 to 9, wherein the thin film forming mechanism includes a plasma generation unit for performing radical oxidation and an oxidizing gas introduction unit.

11. The thin film forming apparatus according to claim 5, wherein the thin film forming mechanism includes a plasma generating unit for performing radical nitriding and a nitriding gas introducing unit.

12. The thin film formation mechanism includes a plasma generation unit for performing radical oxynitriding, and an introduction unit of oxynitriding gas or oxidizing gas and nitriding gas. The thin film forming apparatus according to any one of the above.

13. The thin film forming apparatus according to claim 5, wherein the thin film forming mechanism includes a heating unit for performing thermal oxidation and an oxidizing gas introduction unit.

14. The thin film forming apparatus according to claim 5, wherein the thin film forming mechanism includes a heating unit for performing thermal nitriding and a nitriding gas introduction unit.

15. The thin film formation mechanism includes a heating part for performing thermal oxynitridation, and an introduction part of an oxynitriding gas or an oxidizing gas and a nitriding gas. The thin film forming apparatus described in 1.

16. The thin film forming apparatus according to claim 5, wherein the thin film forming mechanism includes a heating unit for performing CVD film formation and a source gas introducing unit.

[17] The thin film formation mechanism according to any one of [5] to [9], wherein the thin film formation mechanism includes a target for performing sputter deposition, an ion generation unit, a heating unit, and a source gas introduction unit apparatus.

18. The plasma generation unit for performing radical oxidation, radical nitridation, and radical oxynitridation includes a microwave generation unit, a microwave waveguide, and a radial line slot antenna. The thin film forming apparatus according to any one of 12 above.

[19] The plasma generation unit for performing the radical oxidation, radical nitridation, and radical oxynitridation includes parallel plate electrodes to which a high frequency can be applied. Thin film forming equipment.

[20] The CVD film formation is characterized in that at least one gate insulating film thin film selected from the group consisting of SiO, SiN, SiON, HfO, HiSiO, and HfSiON force is formed. Term

16. The thin film forming apparatus according to 16.

21. The thin film forming apparatus according to claim 17, wherein the sputter film formation is a film formation of a base thin film for forming a gate insulating film of S or Hf.

[22] At least from the pre-treatment device that performs the cleaning process, the transport container is transported in an inert atmosphere at atmospheric pressure, through the second-stage load lock chamber and gate valve that prevents or removes organic substances. Connected, and has a mechanism that allows the substrate to be introduced into the second-stage load lock chamber without touching the atmosphere.

The thin film forming apparatus according to any one of claims 5 to 21, wherein the transfer container has a role of a first-stage load lock chamber in which an inert gas atmosphere is maintained at atmospheric pressure.

[23] At least the treatment chamber of the pretreatment device that performs the cleaning process or its load lock chamber is directly connected to the organic substance by preventing adhesion or removing the organic substance through the second load lock chamber force gate valve.

The process chamber of this pretreatment device or its load lock chamber has a role of a first-stage load lock chamber that makes an inert gas atmosphere at atmospheric pressure. The thin film forming apparatus described in 1.

[24] A dielectric film formed on a processing substrate,

The dielectric film according to claim 1, wherein the dielectric film does not include an uncontrolled oxide film.

[25] In the dielectric film, according to claim a Si-C bond, which in the near with the interface between the dielectric film and the treated substrate surface, characterized in that it comprises N 1E + 12 atoms m ² at a concentration 24. The dielectric film according to 24.

26. The dielectric film according to claim 24, wherein the dielectric film contains H at a concentration of 1E + 20 atoms / m ³ or less.

[27] In the dielectric film, the roughness of the interface between the dielectric film and the surface of the processing substrate is R

27. The dielectric film according to claim 24, wherein an MS value is 0.2 nm or less.

[28] In a semiconductor device comprising a processing substrate, a dielectric film formed on the processing substrate, and an electrode formed on the dielectric film,

The semiconductor device, wherein the dielectric film does not include an uncontrolled oxide film.

[29] The dielectric film is claim that the Si-C bonds, and have you in the vicinity of the interface between the dielectric film and the treated substrate surface, characterized in that it comprises N 1E + 12 atoms m ² at a concentration The semiconductor device according to 28.

30. The dielectric film according to claim 21, wherein the dielectric film contains H at a concentration of 1E + 20 atoms / m ³ or less.

28. The semiconductor device according to 28 or 29.

[31] In the dielectric film, the roughness of the interface between the dielectric film and the surface of the processing substrate is an RMS value of 0.

The semiconductor device according to any one of claims 28 to 30, wherein the semiconductor device is awakening or lower.

[32] A method for forming a thin film, characterized in that, when forming a dielectric film on the treated surface, the load-lock chamber is replaced with an inert gas atmosphere at a pressure higher than atmospheric pressure.

[33] The thin film according to [32], wherein when forming the dielectric film on the surface of the processing substrate, the dielectric film is decompressed using a load lock chamber whose inner wall is baked and introduced into the processing chamber. Forming method.

[34] When forming the dielectric film on the surface of the processing substrate, the inner wall is depressurized by using a load-lock chamber that is plasma-cleaned by plasma of a gas not containing carbon such as oxygen, hydrogen, or nitrogen, and the processing chamber is The thin film forming method according to claim 28, wherein the thin film forming method is introduced into the thin film.

[35] A method for manufacturing a semiconductor device, characterized in that, when forming a dielectric film on the surface of a processed substrate, the load-lock chamber is replaced with an inert gas atmosphere at a pressure higher than atmospheric pressure.

36. The semiconductor according to claim 35, wherein when forming the dielectric film on the surface of the processing substrate, the dielectric film is decompressed using a load lock chamber whose inner wall is baked and introduced into the processing chamber. Device manufacturing method.

[37] When forming the dielectric film on the surface of the processing substrate, the inner wall is decompressed using a load-lock chamber that is plasma-cleaned by a plasma of a gas not containing carbon such as oxygen, hydrogen, or nitrogen, and the processing chamber is 36. The method of manufacturing a semiconductor device according to claim 35, wherein the method is introduced into the semiconductor device.

[38] The dielectric film according to any one of [24] to [27], wherein the processing substrate is a silicon substrate.

39. The semiconductor device according to claim 28, wherein the processing substrate is a silicon substrate.

[40] The method for forming a thin film according to any one of [32] to [34], wherein the processing substrate is a silicon substrate.

41. The method for manufacturing a semiconductor device according to claim 35, wherein the processing substrate is a silicon substrate.

42. The dielectric film according to claim 24, wherein the dielectric film is formed by radical oxidation, plasma oxidation, or thermal oxidation.

[43] The semiconductor device according to any one of [28] to [31] or [39], wherein the dielectric film is formed by radical oxidation, plasma oxidation, or thermal oxidation.

44. The method for forming a thin film according to claim 32, wherein the method for forming the dielectric film is radical oxidation, plasma oxidation, or thermal oxidation.

45. The method of manufacturing a semiconductor device according to claim 35, wherein the dielectric film is formed by radical oxidation, plasma oxidation, or thermal oxidation.

46. The method for forming the dielectric film is CVD or sputtering.

The dielectric film according to any one of 4 to 27, 38 or 42.

[47] The method for forming the dielectric film is CVD or sputtering.

48. The semiconductor device according to any one of 8 to 31, 39 or 43.

48. The method for forming the dielectric film is CVD or sputtering.

The method for forming a thin film according to any one of 2 to 34, 40 or 44.

[49] The method of forming a dielectric film according to claim 3, wherein the dielectric film is formed by CVD or sputtering. 46. A method of manufacturing a semiconductor device according to any one of 5-37 or 41 or 45.

A thin film formed on a processing substrate,

The thin film does not contain an uncontrolled oxide film, and contains an organic substance at a concentration of 1E + 12 atoms / m ² or less near the interface between the thin film and the surface of the processing substrate.