JP3649797B2 - Semiconductor device manufacturing method - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a method for manufacturing a semiconductor device that provides a clean semiconductor interface by removing the contamination in a semiconductor device manufacturing process that cannot avoid carbon contamination such as a process in a clean room using a hepper filter. Is.
[0002]
[Prior art]
In the manufacturing method of a semiconductor device, removal of contaminants and prevention of contamination have been established as various methods as an old problem. For removing heavy metals, a method of removing the heavy metal by adding hydrogen peroxide to hydrochloric acid is quite widely known. For removal of physical adsorbates, cleaning using ultrasonic cavitation or cleaning with a brush is often used.
[0003]
For organic substances such as carbon, cleaning with a solution obtained by adding sulfuric acid to hydrogen peroxide water, dry ashing using ozone or oxygen plasma, and the like are well known. However, the inventors' research has shown that there are more complex situations regarding carbon removal. Speaking of where the contamination of carbon comes from, the photoresist used to form an arbitrary pattern during the photolithography process is a photosensitive organic substance, which also causes carbon contamination.
[0004]
In addition, in the manufacture of semiconductor devices, the thin film process is no longer an essential requirement, and a vacuum device for that is also an essential device, but oil is still used for the vacuum pump for evacuating the vacuum device. Some of them also cause carbon pollution. Other than that, Teflon (PFA), polypropylene (PP), polyvinylidene fluoride (PVDF), trifluoroethylene covalent resin (ECTFE), tetrafluoroethylene covalent resin (ETFE), polyethylene ( There is also contamination from vapor pressure from PE), floor materials in clean rooms, and wall materials. These simple substances or composites spread the contamination through the heper filter in the clean room.
[0005]
Dry ashing is performed after the photolithographic process, and immediately before each process, organic substances are removed by using a solution obtained by adding hydrochloric acid to hydrogen peroxide in a 1: 1 ratio by heating to 80 ° C. (hereinafter referred to as wet ashing). Called). The conventional method is to immediately perform the next processing. It seemed that most organic substances could be removed by dry ashing and wet ashing. However, when carbon contamination on the substrate surface was evaluated by known XPS measurement, only the C—C bond (carbon single bond) was obtained. It was found that it was hardly removed.
[0006]
FIG. 2 is a graph showing the degree of carbon impurity removal by XPS on the substrate surface according to the conventional technique.
FIG. 2 shows the substrate surface 21 (broken line graph in FIG. 2) of the substrate left in a clean room for 24 hours after photoresist coating, pre-baking, exposure, development, post-baking and resist stripping, and dry ashing and wet cleaning of the substrate. The surface 22 (solid line graph in FIG. 2) of the substrate after ashing is measured using XPS. As measurement conditions, in order to obtain surface information as much as possible, the angle of the detector was set to 15 °, and an area of 1 mmφ on the substrate surface was measured. The horizontal axis represents the binding energy, the unit is eV, the vertical axis is the intensity of the detector, and the unit is an arbitrary unit.
[0007]
From the graph of FIG. 2, it can be seen that the peak near 284.8 eV increases before and after (solid line) dry ashing and wet ashing, and all other peaks decrease. The peak at 284.8 eV indicates the presence of a C—C single bond.
[0008]
This shows that removing carbon single bonds is very difficult and almost impossible with conventional dry ashing and wet ashing. Since this carbon remains as an impurity on the substrate surface, for example, when an oxide film or the like is formed thereon, carbon remains at the interface with the oxide film, becomes a recombination center at the interface, and causes charge trapping, A semiconductor memory capacitor also causes unintended charge accumulation at the interface of the insulating film, lowers the electrical characteristics of the semiconductor, such as the mobility of the field effect transistor, and the coupling state is not stable. By continuing, the interface state changed with time and reliability was also lowered.
[0009]
In addition, when performing multilayer formation such as two-layer formation of an oxide film or nitrogen-doped oxide film on the surface of the semiconductor, the adhesion of the interface is deteriorated, or when the insulating film is used as a dielectric material of a capacitor, In some cases, it may cause an uncontrollable dielectric characteristic or may form a fixed charge, resulting in a result that does not satisfy the capacity storage function as a capacitor.
[0010]
In the thin film transistor circuit for liquid crystal, the situation at the interface between the gate insulating film of the driver TFT for driving the liquid crystal pixel and the semiconductor as the active layer becomes more serious. When 256 gradations are to be achieved by gradation control using a TFT, the threshold standard deviation between adjacent TFTs needs to be less than about 0.02V. However, contamination due to carbon single bonds or the like increases the interface state density at the interface and causes variations in the threshold value.
[0011]
Interface characteristics are very important characteristics for insulated gate transistors, not just thin film transistors, and are also important for interface characteristics of MOS diodes, MOS transistors, etc. Is a situation that can not be.
[0012]
[Problems to be solved by the invention]
In the semiconductor device manufacturing process, the object is to reduce impurities including carbon containing carbon single bonds (C-C), which cannot be removed by conventional wet ashing and dry ashing, among carbon contaminants on the substrate surface. As a result, deterioration of electrical characteristics due to carbon impurities at various semiconductor formation interfaces, reduction in reliability, and the like are reduced. Further, it is possible to remove contaminants including carbon double bonds other than carbon single bonds, and to carry out the next film formation process before the cleaned surface after the removal is not contaminated again.
[0013]
[Means for Solving the Problems]
In order to make activated hydrogen such as hydrogen radicals or hydrogen ions act effectively, Japanese Patent Application No. 7-256968 and Japanese Patent Application No. 7-256969 by the present applicant are described in detail. -26387 discloses in detail a cleaning method by immersing in an inert gas or hydrogen-induced atmosphere by applying inductive energy.
[0014]
However, as a result of investigating a method for efficiently removing impurities due to C—C single bonds adhering to the substrate surface by activated hydrogen such as hydrogen radicals or hydrogen ions, it was excellent in a cleaning method incorporating high-density plasma technology. It turns out that there are many points. In particular, in the present invention, a plasma using a microwave at a low pressure, a plasma using a microwave and a magnetic field, and a plasma using electron cyclotron resonance (ECR) using a microwave and a magnetic field are used. It relates to making hydrogen into activated hydrogen such as hydrogen radicals or hydrogen ions.
[0015]
In the method using a microwave and a magnetic field, since the distance from the region where plasma is generated to the substrate where plasma processing is performed can be separated to some extent, the substrate to be processed has a charge in active hydrogen or oxygen. It is possible to devise a method for removing the object, or conversely, to devise a method for treating the substrate mainly with an object having a charge.
[0016]
Electron cyclotron resonance is a method in which an electric field and a magnetic field are established so that cyclotron resonance is established, and plasma is generated there to obtain a plasma having a high plasma density, which is called so-called ECR plasma. The characteristics of this ECR plasma are 10 ^-3 -10 ^-1 High-density plasma can be obtained at a low pressure of Pa. Since this pressure region is the so-called molecular flow region pressure, the uniformity of the gas mixing and the partial pressure of the gas in the chamber is much better than the pressure in the laminar and intermediate flow regions. Even when the ECR condition is not satisfied, high-density plasma can be obtained by using a microwave and a magnetic field.
[0017]
The single bond of carbon attached to the surface of a semiconductor material, a metal material, or an insulating material can be reduced by a plasma cleaning method using plasma and hydrogen using a microwave and a magnetic field. Further, by performing film formation using microwaves and magnetic field plasma as it is after the cleaning, so-called in-situ film formation in which the interface is kept clean can be formed.
[0018]
Even when film deposition using microwave and magnetic field plasma is not performed, sputtering can be performed on a clean surface after microwave and magnetic field plasma cleaning in another chamber by using a multi-chamber system. In-situ film formation can be performed using film formation methods other than microwave and magnetic fields, such as thermal CVD and parallel plate plasma CVD.
[0019]
In order to generate ECR plasma when generating plasma by ECR and cleaning the surface of the substrate or what is formed on the substrate (collectively referred to as substrate) with active hydrogen such as hydrogen radicals or hydrogen ions. In addition, hydrogen is introduced into a region where ECR occurs.
[0020]
A certain amount of hydrogen is introduced into the chamber by a flow controller such as a mass flow controller. The upper limit of the amount of hydrogen to be introduced is determined by whether or not the pressure in the chamber inevitably determined by the amount of hydrogen introduced, the chamber volume, the pumping speed of the pump, the compression ratio of the pump, etc. is the desired pressure. Come.
[0021]
When an exhaust pump uses a turbo molecular pump, a complex molecular pump, etc., it is difficult to exhaust light elements for hydrogen compared to exhausting other heavy elements because of the pump's exhaust principle. Because of the disadvantage that the compression ratio is also small, when trying to implement the present invention in an apparatus in which such a pump is used, care should be taken to use a state where there is room in the flow rate and pressure of hydrogen. There is a need.
[0022]
When using a pump with a liquid nitrogen trap in combination with an oil diffusion pump, it is easy to use because the pumping speed and compression ratio for hydrogen are high. However, when film formation is performed as it is in the chamber for plasma cleaning, the nitrogen trap cannot be used because there is a risk of explosion when the reaction gas for film formation is adsorbed to the nitrogen trap and the adsorption amount increases. Because of this, reverse diffusion of oil occurs, and the substrate may be contaminated with carbon, so that the temperature is higher than that of liquid nitrogen and the temperature at which the reaction gas is not adsorbed, and the temperature at which oil is adsorbed. It is necessary to pay attention to using.
[0023]
10 ^-3 Since the mean free path of hydrogen at Pa exceeds 10 m, active hydrogen such as hydrogen radicals and hydrogen ions generated by ECR reaches the substrate almost without colliding with other hydrogen and molecules, and passes through the substrate. Can be processed. Therefore, compared to the method of generating plasma at a pressure of 100 Pa or the like as in a normal parallel plate plasma processing apparatus, it is less likely to reach the substrate in the form that other elements are bonded to active hydrogen, and it is more effective. Thus, the substrate can be cleaned.
[0024]
Active hydrogen that contributes to cleaning is discharged to the outside by a pump immediately after cleaning, and new active hydrogen reaches the substrate surface to clean the substrate. By repeating this, active hydrogen generated by ECR reaches the substrate without colliding with other elements, and a very clean surface can be achieved by cleaning and exhausting the substrate.
[0025]
Active hydrogen breaks single carbon bonds, especially CH _X Such as gas However, the contamination with carbon includes double bonds and the like. Carbon contamination such as double bonds may be dry ashed, and organic matter may be removed by using wet ashing immediately before each step, followed by cleaning with active hydrogen according to the present invention. Performing dry ashing using a microwave and a magnetic field in the same chamber is an efficient process.
[0026]
For example, oxygen is introduced into a chamber in the ECR region. A certain amount of oxygen is introduced into the chamber by a flow controller such as a mass flow controller. The upper limit of the amount of oxygen to be introduced is determined by whether or not the pressure in the chamber inevitably determined by the amount of oxygen introduced, the chamber volume, the pumping speed of the pump, the compression ratio of the pump, etc. is the desired pressure. Come.
[0027]
When the exhaust pump uses a turbo molecular pump or a complex molecular pump, heavier elements for oxygen are easily exhausted, unlike hydrogen, because of the exhaust principle of the pump. Further, when the present invention is to be implemented in an apparatus in which such a pump is used because the compression ratio is large, it is easy to implement.
[0028]
A pump using a liquid nitrogen trap in combination with an oil diffusion pump can also be used. However, when film formation is performed as it is in the chamber for plasma cleaning, the nitrogen trap cannot be used because there is a risk of explosion when the reaction gas for film formation is adsorbed to the nitrogen trap and the adsorption amount increases. Because of this, reverse diffusion of oil occurs, and the substrate may be contaminated with carbon, so that the temperature is higher than that of liquid nitrogen and the temperature at which the reaction gas is not adsorbed, and the temperature at which oil is adsorbed. It is necessary to pay attention to using. It should also be noted that the oil for the oil diffusion pump is likely to oxidize at high temperatures, and that exhausting a large amount of oxygen may reduce the pumping capacity of the pump.
[0029]
10 ^-3 Since the mean free path of oxygen at Pa exceeds 6 m, active oxygen such as oxygen radicals and oxygen ions generated by ECR hardly collides with other oxygen and molecules unless it is a very large device. The substrate can be processed. Therefore, compared to the method of generating plasma at a pressure of 100 Pa or the like as in a normal parallel plate plasma processing apparatus, it is less likely to reach the substrate in the form that other elements are bonded to active oxygen, and it is more effective. Thus, the substrate can be cleaned.
[0030]
The active oxygen contributing to the cleaning is exhausted to the outside by the pump immediately after the cleaning, and the new active oxygen reaches the substrate surface to clean the substrate. By repeating this, active oxygen generated by ECR reaches the substrate without colliding with other elements, and the substrate is cleaned and exhausted to achieve a very clean surface.
[0031]
Active oxygen breaks carbon double bonds, etc. _X Use a substrate such as for cleaning. That is, by using both active oxygen and active hydrogen, a single bond double bond of carbon and the like can be removed, so that it can be applied to almost all carbon contaminants.
[0032]
First, oxygen is introduced to generate active oxygen, thereby removing carbon contaminants other than single bonds including carbon double bonds from the substrate, stopping oxygen introduction, and then introducing hydrogen to activate hydrogen. Can be performed in the same chamber, thereby removing carbon contaminants primarily due to carbon single bonds. Conversely, hydrogen is first introduced to generate active hydrogen, thereby removing carbon contamination mainly containing carbon single bonds from the substrate, stopping hydrogen introduction, and then introducing oxygen to produce active oxygen. Thus, a cleaning method for removing carbon contaminants other than a single bond including a carbon double bond from the substrate can be performed in the same chamber.
[0033]
At the same time, hydrogen and oxygen are introduced, and active hydrogen such as hydrogen radicals and hydrogen ions and active oxygen such as oxygen radicals, oxygen ions, and ozone are generated simultaneously by plasma generated by microwaves and magnetic fields. It is also possible to simultaneously reduce most of the carbon contamination including both single and double bonds of carbon.
[0034]
Alternatively, hydrogen and oxygen may be supplied simultaneously by introducing water as a source into the chamber. In this case, H ₂ Since O is always in a 2: 1 ratio between hydrogen and oxygen, H is adjusted to adjust the flow ratio of hydrogen and oxygen. ₂ It is also effective to introduce a tank containing O 2 into the chamber by bubbling with oxygen.
[0035]
Water may be directly vaporized by heating and introduced into the chamber. When water is introduced into the chamber, it is better to leave all the piping up to the introduction heated. When not heated, water is easily adsorbed, so the degree of vacuum is likely to decrease. Even when the substrate is cleaned, the surface is cleaned with active hydrogen or active oxygen because the degree of vacuum is poor. May not be held for a long time.
[0036]
In addition, if the chamber is possible, it is better to heat it as a whole, and it is possible to greatly reduce the adsorption of water by heating to 80 ° C. or higher. Further, the adsorption may be reduced by treating the pipe and the inner wall of the chamber by electropolishing or complex electropolishing.
[0037]
As an electric field and a magnetic field for generating a plasma by a microwave and a magnetic field, a method of generating a static magnetic field by using a coil such as soleinoid or Helmholtz and causing a direct current to flow therethrough is well known. As for the generation of the electric field, a microwave of 1 to 10 GHz is guided to the chamber through the waveguide, and the boundary between the chamber and the end of the waveguide is formed of a material such as quartz, synthetic quartz, or magnesium fluoride.
[0038]
The microwave travels through the waveguide through atmospheric pressure up to the chamber, but since the chamber is in a reduced pressure state, a window material is required to complete it. In addition, in order to give more electric field energy by microwaves to electrons using cyclotron resonance, it is effective to install a microwave cavity resonator in the chamber. Large energy can be given to electrons by forming an ECR at the antinode of the standing wave of the microwave in the cavity resonator.
[0039]
However, even when the cavity resonator is not used, it is possible to sufficiently use the microwave and the magnetic field plasma. The magnetic field can change the spatial position of the high-density plasma by the microwave and the magnetic field by changing the direct current flowing through the solenoid coil. Of course, the spatial position of the high-density plasma by the microwave and the magnetic field can also be changed by changing the frequency of the microwave while keeping the magnetic field constant.
[0040]
Plasma generated by the microwave and magnetic field diffuses along the diffusion magnetic field. When the substrate to be plasma-treated is small with respect to the spread of the plasma to be diffused in the direction of the substrate surface at the position of the substrate to be treated by this diffusing plasma, there is no particular problem. However, when the substrate becomes larger, the plasma density such as the electron density of the plasma at the central portion of the substrate and the end portion of the substrate becomes greatly different. When the plasma density is different, the processing using the plasma density is also different.
[0041]
The substrate is disposed at a position where the plasma formed by the microwave and the magnetic field diffuses from the high-density region of the plasma in the direction opposite to the position where the microwave is introduced. The position of the substrate may be close to the high density plasma or away from the plasma depending on the plasma diffusion method and the size of the substrate. When the substrate is small, it can be brought closer to high density plasma than when the substrate is large.
[0042]
If it is possible to approach the high-density plasma region, processing at a position where the plasma density is higher is possible, but if it is far from the high-density plasma region, processing is performed at a position where the plasma density is low. Even if the substrate must be placed away from the high-density plasma region because it is large, the magnetic field diffusion gradient can be made as small as possible, or the diffused plasma can be reduced by using a mirror magnetic field. The effects can be made as small as possible.
[0043]
As cleaning to remove carbon contamination on the surface of the substrate, the present invention includes reduction of carbon contaminants including carbon single bonds due to active hydrogen and carbon double bonds other than carbon single bonds due to active oxygen. Although carbon contamination is reduced simultaneously or individually, the surface state of the substrate changes variously during the manufacturing process.
[0044]
If carbon contamination is reduced by cleaning according to the present invention before the base underlayer is formed when nothing has been formed on the surface of the substrate, active hydrogen and active oxygen are simultaneously applied to the microwave and magnetic field. The substrate surface is cleaned by exposing it to active hydrogen such as hydrogen radicals or hydrogen ions, or active oxygen such as oxygen radicals, oxygen ions or ozone. The cleaning order of active hydrogen and active oxygen may be started from either or simultaneously.
[0045]
However, after forming a transistor that uses a thin gate insulating film such as a MOS transistor, active hydrogen and active oxygen are simultaneously converted into plasma by a microwave and a magnetic field according to the present invention, and the substrate surface is made of hydrogen radicals, hydrogen ions, etc. When the substrate surface is cleaned by exposure to active hydrogen, active radicals such as oxygen radicals, oxygen ions, or ozone, electrostatic breakdown of the gate insulating film due to charge-up is fatal and plasma Handling charged particles in the process and how to escape the charge are important.
[0046]
When the substrate uses single crystal silicon, the substrate is P ^- Or N ^- Therefore, the resistance of the substrate is small, so that the charge-up of the substrate is very small compared to the insulating substrate. However, in recent semiconductors, there is a case where a considerably thick interlayer insulating film is formed as a three-dimensional IC and a plurality of wirings are formed thereon. In such a case, when the present invention is used, it is affected by the charge-up.
[0047]
In the case of active matrix liquid crystal thin film transistors, gate insulating transistors are provided on an insulating substrate, and in the case of RGB color of 640 × 480 pixels, only the pixel portion, and the pixel switching TFT is 900,000 elements. If one of them does not work, it becomes a point defect, and the product value of the final product is greatly reduced. In such a situation, a countermeasure for charge-up of the substrate when using the present invention after forming the gate insulating film of the TFT is important.
[0048]
In the present invention, active hydrogen and active oxygen are generated by plasma using a microwave and a magnetic field, thereby reducing carbon contamination on the surface of the substrate. Some have That is, hydrogen ions, oxygen ions, and electrons.
[0049]
In order to control the charge-up of the substrate by hydrogen ions, oxygen ions, and electrons having this charge, the charge charged up from the substrate surface is quickly released to the earth or the like, or the substrate is not charged, that is, hydrogen ions, oxygen ions To prevent electrons from reaching the substrate. For example, in the ECR, the distance from the ECR region to the substrate is longer than the distance from the cathode to the substrate of the parallel plate type plasma apparatus, and the plasma generation pressure is 10 ^-3 -10 ^-1 Since it is as low as Pa, the mean free path is as long as several meters.
[0050]
Therefore, hydrogen ions, oxygen ions, and electrons can be taken away by colliding with the ground potential before reaching the substrate by a magnetic field and an electric field. The original hydrogen ions and the original oxygen ions from which charges have been removed have a long mean free path, so that they do not collide with other charged particles, and are exhausted as they are as neutral elements. Therefore, it is less likely that the substrate is charged, and as a result, the destruction of the semiconductor can be reduced, so that the effect of the present invention of only the cleaning effect is produced.
[0051]
In order to prevent such hydrogen ions, oxygen ions, and electrons from reaching the substrate, a magnetic field directed to the ground potential such as a chamber wall is formed in the space before reaching the substrate, thereby generating hydrogen ions generated in the ECR region, Oxygen ions and electrons pass the electric charge that collides with the ground potential along the magnetic field to the ground potential, and become neutral elements. The electrons disappear there.
[0052]
In order to prevent hydrogen ions, oxygen ions, and electrons from reaching the substrate, a DC electric field is applied to the space before reaching the substrate so that positive charges are directed to the cathode and negative charges are directed to the anode. This reduces hydrogen ions, oxygen ions, and electrons that reach the substrate, thereby reducing the charge-up of the substrate. However, in order to prevent charged particles from reaching the substrate by an electric field, a direct current discharge is generated between the electrodes when the electric field is formed by applying a very large voltage.
[0053]
In the present invention using ECR, since the pressure is low, it is difficult to discharge easily depending on the distance between the electrodes. It is also effective to remove a charge from charged hydrogen ions or oxygen ions by providing a ground potential grid or the like between the ECR region and the substrate.
[0054]
FIGS. 5A and 5B show the principle of removing charged hydrogen from active hydrogen or active oxygen. In FIG. 5A, in the plasma 5000 composed of active hydrogen, active oxygen, or the like, there are charges such as ions 5003 and electrons 5004 and charges such as neutral radicals 5002 and molecular atoms 5001. There are things that do not have.
[0055]
The substrate 5005 reaches the substrate 5005 with various charges such as ions 5003 and electrons 5004 and those having no charge such as neutral radicals (including ozone) 5002 and molecular atoms 5001. Carbon contaminants on the substrate 5002 react with neutral radicals 5002 and ions 5003 to react with CH. _X Or CO _X Vaporize in the form of
[0056]
However, in the case where the ions 5003 and the electrons 5004 adversely affect the substrate 5005, the charged ions 5003 or the electrons 5004 are removed before the plasma 5000 reaches the substrate 5005 as shown in FIG. Further, removal is performed by removal functions 5006 and 5007 for generating a diffusion magnetic field and an electric field. Those with charge use it to behave in a magnetic or electric field to follow its gradient.
[0057]
The ions 5003 and the electrons 50004 lost by the charge removal function 5006 and 5007 become the neutral molecular atoms 5001 and the electrons 5004 disappear, and the substrate 5005 has almost all the neutral radicals 5002 and the molecular atoms 5001. It becomes.
[0058]
In the process of the semiconductor process, there is a case where it is better to have a sputtering effect due to ions. When removing carbon contaminants using the present invention before forming a base film on the substrate, the substrate was subjected to ions to some extent in order to improve the adhesion between the base film and the substrate to be formed later. Sometimes it is better to strike.
[0059]
In such a case, it is preferable to positively guide ions to the substrate. For this purpose, a bias is applied to the substrate and the substrate is struck by ions while performing cleaning using the present invention. For this purpose, self-bias by high frequency is used rather than DC bias.
[0060]
As the bias by high frequency, a sufficient self-bias can be applied to the substrate surface regardless of whether the substrate is an insulator or a semiconductor. Since there is a blocking capacitor between the high frequency power supply and the substrate support for holding the substrate as a matching device for applying a high frequency, a self-bias is generated there.
[0061]
The self-bias depends on whether the ions accelerated to the substrate are positive or negative depending on whether the substrate support is connected to be the cathode or the anode. Since the hydrogen ions are positive, in order to accelerate them to the substrate, the substrate side is connected so as to be a cathode, thereby causing the hydrogen positive ions to collide with the substrate. The collision with hydrogen ions has no large sputtering effect because the mass of hydrogen ions is small, so in order to improve the adhesion of the film formed after the cleaning and sputtering with hydrogen ions, etc. Any process can be used.
[0062]
Since oxygen ions are negative, in order to accelerate them to the substrate, the substrate side is connected so as to be an anode, thereby causing oxygen negative ions to collide with the substrate. The collision with oxygen ions has a large sputtering effect due to the large mass of oxygen ions. Therefore, in order to improve the adhesion of the film formed after cleaning and sputtering with oxygen ions, etc. It is used in consideration of the characteristics of the film formation surface.
[0063]
In addition, using an inert gas having a large mass such as argon as the plasma generated by the ECR plasma is very effective when obtaining a large sputtering effect. Therefore, a large sputtering effect can be obtained by using a mixture of inert gas such as hydrogen or oxygen and argon and applying a bias so that the substrate side becomes a cathode.
[0064]
Argon also has the effect of physically removing carbon contamination that cannot be removed chemically in order to physically scrape the substrate surface that collided by sputtering, combined with the chemical effect of the present invention. A synergistic effect can be obtained.
[0065]
In addition, thin film transistors using polysilicon, thin film transistors using amorphous silicon, thin film transistors using mixed crystal silicon, etc., there is a hydrogenation process as the termination of the gray bandary. The process can also be performed by the cleaning of the present invention.
[0066]
After hydrogenation, an oxide film or nitride film is formed as a passivation film to protect the completed transistor, but if hydrogenation is not performed before that, hydrogen for hydrogenation by the passivation film is the passivation film. It is blocked by the membrane and does not reach the area where it is actually desired to hydrogenate. The cleaning of surface carbon contamination by active hydrogen such as hydrogen radicals and hydrogen ions of the present invention also serves as this hydrogenation.
[0067]
That is, passivation can be performed by in-situ film formation on a transistor that has been cleaned and hydrogenated, has a clean surface, and has a grain boundary terminated with hydrogen. Thus, a transistor with high characteristics can be realized.
[0068]
In order to enhance the cleaning effect of the substrate and perform in-situ film formation, the substrate is preferably heated. The substrate is heated by connecting a resistance heater to the substrate support. In this case, when the substrate bias is performed at a high frequency, high frequency noise can be avoided by using an insulating transformer as the heater heating transformer.
[0069]
The upper limit of the heating of the substrate is also determined by the material formed on the substrate and the material of the substrate, but the higher the substrate temperature, the greater the cleaning effect. Further, if the temperature is the same as the temperature of the film to be formed next, the time until in-situ film formation is short, and throughput and tact time can be improved. However, the present invention using a microwave and a magnetic field can obtain a sufficient cleaning effect even at room temperature.
[0070]
In addition, after the cleaning according to the present invention is completed using a multi-chamber, the next film formation can be performed in another chamber without exposure to the atmosphere. Of course, the next film formation can be continued using a microwave and a magnetic field in the cleaned chamber.
[0071]
The substrate surface on which nothing is formed is generated by using plasma generated by microwave and magnetic field to generate active hydrogen and active oxygen, thereby reducing carbon contamination on the substrate surface. Then, a silicon oxide film using organosilane and oxygen is formed as a base film using a parallel plate type plasma CVD apparatus. As the silicon oxide film, a nitrogen-doped silicon oxide film can be formed using nitrogen oxide or a mixed gas of nitrogen oxide and oxygen instead of oxygen. Instead of the oxide film, a silicon nitride film can be formed using silane, ammonia, and nitrogen as a base film.
[0072]
In addition, when aluminum is sputtered onto the gate insulating film as a gate electrode, active hydrogen and active oxygen are generated using microwave and magnetic field plasma, thereby reducing carbon contamination on the substrate surface. Let At this time, since the cleaning is to clean the surface of the gate insulating film, in order to prevent dielectric breakdown of the gate insulating film due to charge-up, a magnetic field for making it difficult for hydrogen ions and oxygen ions to reach the substrate Is generated between the substrate and the high-density plasma region, whereby before the hydrogen ions and oxygen ions reach the substrate, the surface of the gate insulating film is cleaned so as to release the charge.
[0073]
Thereafter, the substrate is moved to another chamber, where magnetron sputtering of aluminum which is a film for the gate electrode is performed. If the sputtered film is a multilayer, the substrate can be moved to another chamber and another film such as chromium can be formed by sputtering.
[0074]
When an interlayer insulating film of an SRAM having a polysilicon TFT is formed, an aluminum wiring or an oxide film is formed on the film formation surface. However, the film formation surface is formed by a microwave and a magnetic field. Plasma is used to generate active hydrogen and active oxygen, thereby reducing carbon contamination on the substrate surface. At that time, the surface cleaning with active hydrogen simultaneously performs hydrogenation of the polysilicon TFT.
[0075]
After the reduction of carbon contaminants and hydrogenation are completed, a silicon oxide film is formed by plasma using a microwave and a magnetic field in the same chamber. In order to form an oxide film using plasma by a microwave and a magnetic field, oxygen is introduced into the high density plasma region, and silane is introduced between the substrate and the high density plasma region to form the oxide film. At that time, planarization can also be achieved by using a process in which bias sputtering is combined by applying a bias to the substrate. The oxide film formed by the microwave and magnetic field has a high density, and hydrogen that has terminated the grain boundary due to hydrogenation is difficult to escape, so that cleaning and hydrogenation can be performed simultaneously.
[0076]
Of course, when forming an oxide film, hydrogen can be made more difficult to escape by forming a nitrogen-doped oxide film by doping nitrogen. In addition, by adding fluorine, the dielectric constant can be slightly lower than that of an oxide film to which no fluorine is added, and an interlayer film having a small stray capacitance can be formed.
[0077]
When the laminated device in which the cleaning according to the present invention was completely performed before film formation was measured by secondary ion mass spectrometry (SIMS), the lowest value of the amount of carbon impurities at each interface was 8 × 10. ¹⁸ ~ 7 × 10 ¹⁹ cm ^-3 The level of the carbon impurities at each interface was 5 × 10 5 when the cleaning according to the present invention was not performed under the same film forming conditions. ¹⁹ ~ 3x10 ²⁰ cm ^-3 The amount of carbon at the interface is small.
[0078]
By cleaning the substrate surface according to the present invention, a film having a high hardness after cleaning or a film having a high density can be easily formed because of high adhesion. In other words, as an interlayer insulating film for memory, silicon oxide for planarization is formed by reflow using organosilane, or film formation is performed by utilizing the step coverage of organosilane using atmospheric pressure CVD. It was.
[0079]
However, these films are highly hygroscopic and reduce the reliability of the semiconductor. Further, planarization using CMP (Chemical Mechanical Polishing), which has recently been used in semiconductor processes, cannot be used because the film is too soft and has high hygroscopicity.
[0080]
Silicon oxide film formation using a microwave and a magnetic field is used as an interlayer insulating film that is flattened according to the high density and hardness of the oxide film by the microwave and the magnetic field when used in combination with CMP. However, the high density and hardness of the film may cause peeling or cracking of the film during the CMP process.
[0081]
Since the surface of the substrate that has been cleaned using the present invention has improved adhesion, an oxide film or a nitrogen-doped oxide film using microwaves and magnetic field plasma that does not easily cause peeling or cracking is formed. Can be membrane. Furthermore, using the multi-chamber system, after performing cleaning according to the present invention using microwaves and magnetic field plasma, it is more possible to form the next high density and high hardness film without exposure to the atmosphere. It is effective.
[0082]
Of course, it is possible to perform cleaning using high frequency as well as cleaning using microwaves and magnetic field plasma. When using a high frequency, for example, at a frequency of 13.56 MHz or less, the pressure is processed at about 0.1 to 2 Torr, at 20 to 300 MHz, processed at about 0.01 to 0.1 Torr, and at 300 MHz or more, 0.001 to 0 is processed. Process at about 01 Torr. This is because the ionization rate increases as the frequency increases.
[0083]
FIG. 1 is a graph showing the degree of carbon impurity removal by XPS on the substrate surface according to the present invention.
Substrate surface 11 after photoresist coating, pre-baking, exposure, development, post-baking, resist stripping (dotted line graph in FIG. 1), and substrate surface 12 after dry ashing and wet ashing of the substrate (FIG. 1) (Dotted line graph in FIG. 1) is the substrate surface 13 after removing carbon impurities using the present invention after photoresist coating, pre-baking, exposure, development, post-baking, resist stripping (solid line graph in FIG. 1). Was measured using XPS. As measurement conditions, in order to obtain surface information as much as possible, the angle of the detector was set to 15 °, and an area of 1 mmφ on the substrate surface was measured. The horizontal axis represents the binding energy, the unit is eV, the vertical axis is the intensity of the detector, and the unit is an arbitrary unit.
[0084]
From the graph of FIG. 1, it can be seen that the peak near 284.8 eV increases before and after the dry ashing and wet ashing 12 and all other peaks decrease. Moreover, it can be seen that the peak near 284.8 eV is greatly reduced in the graph 13 using the present invention. The reason why the peak does not become completely zero even when the present invention is used is that the measurement is not in-situ measurement, and after removing the carbon impurity using the present invention, there is a gap between the adhering carbon impurities. It appears to be. However, a significant effect is seen compared to the case where the present invention is not used. By using the present invention, carbon contaminants having a carbon single bond can be reduced.
[0085]
[Action]
By using the present invention, carbon impurities that could not be removed by conventional dry ashing or wet ashing can be greatly reduced in the manufacture of semiconductor devices. It is particularly effective for removing impurities and contaminants containing carbon single bonds represented by C—C, and makes it difficult for ions to reach the substrate, and is charged by neutral and active hydrogen or oxygen such as radicals. Contaminants can be removed in a small number of situations, and it can be carried out while preventing damage due to semiconductor charge-up, etc., and the interface at the time of semiconductor stacking is cleaned, improving electrical characteristics and reliability. Cannot be measured.
[0086]
【Example】
[Example 1]
FIG. 3 shows an apparatus for carrying out the present invention. The figure shows the configuration of the longitudinal section of the apparatus. A microwave waveguide 3001 is connected to the cavity resonance chamber 3030 so as to cover the microwave introduction window 3002. For the introduction window 3002, quartz, synthetic quartz, magnesium fluoride, or the like is used, but synthetic quartz is used in this embodiment. The cavity resonance chamber 3030 is connected to the taper chamber 3032, and there is a reflection plate 3031 between them, and the cavity resonance chamber 3030 transmits the microwave reflected by the reflection plate 3031 and the microwave traveling through the introduction window 3002. A standing wave is formed between them.
[0087]
The tapered chamber 3032 is connected to the reaction chamber 3033. The reaction chamber 3033 is connected to a pump 3036 via a pump valve 3034 and a conductance regulator 3035. The pump 3036 exhausts unnecessary gas and the like to the exhaust pipe 3037. The connection order of the pump valve 3034 and the conductance adjuster 3035 may be reversed. The conductance regulator 3035 and the pump valve 3034 control the pressure in the reaction chamber 3033, the taper chamber 3032, and the cavity resonance chamber 3030. As the pump 3036, a turbo molecular pump, a complex molecular pump, an oil diffusion pump, or the like is used. Although not shown, these pumps are used by connecting an auxiliary pump such as an oil rotary pump to the exhaust side of the pump. In this example, a dry pump was used as the composite turbo molecular pump and the auxiliary pump.
[0088]
The reaction chamber 3033 is connected to another decompression chamber 3054 with a gate valve 3050 that is moved by a hinge 3051. Here, it is needless to say that it is not connected to another decompression chamber 3054 and may be used as a single device. When not connected to another decompression chamber 3050, it may be closed like a gate valve 3053 connected by a hinge 3055. The gate valve 3050 can be opened like an open state 3052 around the hinge 3051. Here, it goes without saying that the gate valve 3050 may be a slide type valve.
[0089]
There is a means for holding the substrate in the reaction chamber. The right side of the center line 3060 represents the position when the substrate 3076 is unloaded or loaded. The left side of the center line 3060 represents a state where the substrate 3075 is fixed. In both cases, there are actually halves that are not shown symmetrically with respect to the center line 3060, but in the figure, halves are shown so that both states can be seen.
[0090]
On the right side of the center line 3060 indicating the state during loading / unloading, the substrate 3076 is floated from the substrate support 3070 by the pusher pin 3072. Further, the substrate fixing device 3074 moves in conjunction with the pusher pin 3072 so that the substrate 3076 is not fixed and the substrate 3076 becomes movable.
[0091]
On the left side of the center line 3060 indicating the state in which the substrate 3075 is fixed, the pusher pin 3071 is accommodated in the substrate support 3070, and in conjunction with the pusher pin 3071, the substrate fixing device 3073 attaches the substrate 3075 to the substrate support 3070. Fix so that it is in close contact.
[0092]
Although not shown, a heater that can heat the substrate 3075 is embedded in the substrate support 3070. A high frequency power source 3080 for applying a high frequency bias is connected to the substrate support 3070 through a matching unit 3081. The matching unit 3081 contains a blocking capacitor, and a high frequency bias is applied to the substrate 3075 by a self-bias applied to the blocking capacitor.
[0093]
A solenoid coil 3020 for generating a magnetic field is installed around the cavity resonance chamber 3030. By applying a direct current to the solenoid coil 3020, a magnetic field necessary for electron cyclotron resonance is created as a high-density plasma region in the cavity resonance chamber 3030. When a 2.45 GHz microwave is introduced from the waveguide 3001, an ECR condition can be created in the cavity resonance plasma region 3040 by generating a magnetic field of 875 Gauss by a solenoid coil.
[0094]
Around the taper chamber 3032, diffusion magnets 3021 and 3022 for plasma diffusion are arranged. The diffusion magnets 3021 and 3022 are used in accordance with their purposes, whether permanent magnets or electromagnets. Even in the case of an electromagnet, it is not always necessary to be coiled.
[0095]
The gas is introduced by top pipes 3001 and 3011 introduced into the cavity resonance chamber 3030, a taper pipe 3012 introduced into the taper chamber 3032, and 3013 introduced into the reaction chamber 3033. Reaction using ECR has a reaction pressure of 10 ^-1 Since it is as low as Pa or less, there is little need to make the gas flow very strict.
[0096]
In order to remove carbon contaminants adhering to the surface of the substrate 3075, oxygen is first introduced from the top pipe 3001 into the cavity resonance chamber 3030. Pressure is 10 ^-3 -10 ^-1 Set to about Pa. In this embodiment, 3 × 10 ^-2 Performed at Pa. A direct current is passed through the solenoid coil 3020 and a current value of 875 Gauss is measured in the cavity resonance plasma region 3040 in advance, and the current value is passed. The microwave introduced 2.45 GHz from the waveguide 3001. As the microwave power, 500 to 2000 W was introduced, and in this embodiment, 1200 W was introduced. As the substrate 3075, a silicon wafer, a semiconductor such as gallium arsenide, or an insulator such as glass or quartz is used. In this embodiment, an 8-inch silicon wafer is used.
[0097]
The ECR condition is achieved by the microwave and the magnetic field generated by the solenoid coil 3020, whereby ECR plasma having a high electron density is generated in the cavity resonance plasma region 3040. In the ECR plasma, oxygen partially changes to oxygen ions, oxygen radicals, and ozone. Active oxygen such as oxygen ions, oxygen radicals, and ozone reaches the surface of the substrate 3075 along the diffusion magnetic field of the solenoid coil 3020.
[0098]
If the substrate is not as large as the diameter of the cavity resonance chamber 3030 or the opening of the reflecting plate 3031, for example, a silicon wafer having a diameter of 4 inches, the active material that reaches the substrate 3075 by the diffusion magnetic field created by the solenoid coil 3020. Oxygen can sufficiently remove carbon contaminants excluding carbon single bonds. However, when an 8-inch φ silicon wafer is used as the substrate 3075 as in this embodiment, active oxygen generated in the cavity resonance plasma region 3040 is sufficiently removed to sufficiently remove the end of the 8-inch φ wafer. In order to widen the range, diffusion magnets 3021 and 3022 disposed in the taper chamber 3032 are used.
[0099]
The diffusion magnets 3021 and 3022 are set so that the magnetic field gradually changes as it approaches the substrate 3075 gradually and gradually so that the plasma reaches the substrate 3075 uniformly. As a result, the magnetic field that changes rapidly only by the magnetic field of the solenoid coil 3020 does not change greatly, but changes slowly and produces more uniform active oxygen on the substrate 3075 than in the case of the solenoid coil 3020 alone in the tapered plasma region 3051. Can do.
[0100]
Further, in the case where some spatter may be present on the substrate 3075, a substrate bias is applied to the substrate holding table 3070 by the high frequency power source 3080. Since oxygen ions are negative, a bias is applied so that the substrate holder 3070 becomes an anode. Accordingly, the surface of the substrate 3070 is struck by oxygen ions in the substrate plasma region 3042, thereby making it easier to remove carbon contaminants.
[0101]
Oxygen can be converted to active oxygen using ECR, thereby removing carbon contaminants that remove carbon single bonds such as C—C.
[0102]
Next, hydrogen is first introduced into the cavity resonance chamber 3030 from the top pipe 3001 in order to remove contaminants including single carbon bonds attached to the surface of the substrate 3075. Pressure is 10 ^-3 -10 ^-1 Set to about Pa. In this embodiment, 3 × 10 ^-2 Performed at Pa. A direct current is passed through the solenoid coil 3020 and a current value of 875 Gauss is measured in the cavity resonance plasma region 3040 in advance, and the current value is passed. The microwave introduced 2.45 GHz from the waveguide 3001. As the microwave power, 500 to 2000 W was introduced, and in this embodiment, 1200 W was introduced. As the substrate 3075, a silicon wafer, a semiconductor such as gallium arsenide, or an insulator such as glass or quartz is used. In this embodiment, an 8-inch silicon wafer is used.
[0103]
The ECR condition is achieved by the microwave and the magnetic field generated by the solenoid coil 3020, whereby ECR plasma having a high electron density is generated in the cavity resonance plasma region 3040. In the ECR plasma, hydrogen partially changes to hydrogen ions or hydrogen radicals. Active hydrogen such as hydrogen ions and hydrogen radicals reaches the surface of the substrate 3075 so as to follow the diffusion magnetic field of the solenoid coil 3020.
[0104]
If the substrate is not as large as the diameter of the cavity resonance chamber 3030 or the opening of the reflecting plate 3031, for example, a silicon wafer having a diameter of 4 inches, the active material that reaches the substrate 3075 by the diffusion magnetic field created by the solenoid coil 3020. Hydrogen can sufficiently remove carbon contaminants containing carbon single bonds. However, when an 8-inch φ silicon wafer is used as the substrate 3075 as in this embodiment, active hydrogen generated in the cavity resonance plasma region 3040 is sufficiently removed to sufficiently remove the end of the 8-inch φ wafer. In order to widen the range, diffusion magnets 3021 and 3022 disposed in the taper chamber 3032 are used.
[0105]
The diffusion magnets 3021 and 3022 are set so that the magnetic field gradually changes as it approaches the substrate 3075 gradually and gradually so that the plasma reaches the substrate 3075 uniformly. As a result, the magnetic field that changes rapidly only by the magnetic field of the solenoid coil 3020 does not change greatly, but changes slowly and produces more uniform active hydrogen on the substrate 3075 than in the case of the solenoid coil 3020 alone in the tapered plasma region 3041. Can do.
[0106]
Further, in the case where some spatter may be present on the substrate 3075, a substrate bias is applied to the substrate holding table 3070 by the high frequency power source 3080. Since hydrogen ions are positive, a bias is applied so that the substrate holder 3070 becomes a cathode. Accordingly, the surface of the substrate 3070 is struck by hydrogen ions in the substrate plasma region 3042, thereby making it easier to remove carbon contaminants.
[0107]
Hydrogen can be converted to active hydrogen using ECR, thereby removing carbon contaminants containing carbon single bonds such as C—C.
[0108]
Using this device, hydrogen and oxygen can be introduced simultaneously from the top pipe 3010 or separately from the top pipes 3010 and 3011 to simultaneously remove carbon contaminants containing both single and double bonds. It is. In this case, since the polarities of hydrogen ions and oxygen ions are different from positive and negative, the effect of hitting the substrate only with respect to either one of the ions by high frequency substrate bias can be obtained.
[0109]
Instead of introducing hydrogen and oxygen simultaneously, hydrogen and oxygen may be simultaneously cleaned by heating a tank containing water and introducing water vaporized from the vapor pressure into the chamber. In this case, the entire chamber, that is, the cavity resonance chamber 3030, the taper chamber 3032, the reaction chamber 3033, and the piping to the chamber into which water is introduced are all heated. The heating temperature is required to be about 60 to 400 ° C. In this embodiment, since many Viton O-rings are used for vacuum packing, heating is performed at 150 ° C.
[0110]
With such an apparatus, when an 8-inch silicon wafer is cleaned, a substrate having a clean surface as shown in graph 13 of FIG. 1 can be obtained.
[0111]
[Example 2]
FIG. 4 shows an apparatus for carrying out the present invention. The figure shows the configuration of the longitudinal section of the apparatus. A microwave waveguide 4001 is connected to the cavity resonance chamber 4030 so as to cover the microwave introduction window 4002. As the introduction window 4002, quartz, synthetic quartz, magnesium fluoride or the like is used, but synthetic quartz is used in this embodiment. The cavity resonance chamber 4030 is connected to the taper chamber 4032 but there is no reflector between them. Since the cavity resonance chamber 4030 has no reflector, no standing wave is formed between the reflected microwave and the microwave traveling through the introduction window 4002.
[0112]
The tapered chamber 4032 is connected to the reaction chamber 4033. The reaction chamber 4033 is connected to a pump 4036 via a pump valve 4034 and a conductance regulator 4035. The pump 4036 exhausts unnecessary gas or the like to the exhaust pipe 4037. The connection order of the pump valve 4034 and the conductance adjuster 4035 may be reversed. The conductance regulator 4035 and the pump valve 4034 control the pressure in the reaction chamber 4033, the taper chamber 4032, and the cavity resonance chamber 4030. As the pump 3036, a turbo molecular pump, a complex molecular pump, an oil diffusion pump, or the like is used. Although not shown, these pumps are used by connecting an auxiliary pump such as an oil rotary pump to the exhaust side of the pump. In this example, a dry pump was used as the composite turbo molecular pump and the auxiliary pump.
[0113]
In the reaction chamber 4033, a gate valve 4050 that is moved by a hinge 4051 is connected to another decompression chamber 4054. Here, it is needless to say that it is not connected to another decompression chamber 4054 and may be used as a single device. When not connected to another decompression chamber 4050, it may be closed like a gate valve 4053 connected by a hinge 4055. The gate valve 4050 can be opened in the open state 4052 around the hinge 4051. Here, it goes without saying that the gate valve 4050 may be a sliding valve.
[0114]
There is a means for holding the substrate in the reaction chamber. The right side of the center line 4060 represents the position when the substrate 4076 is unloaded or loaded. The left side of the center line 4060 represents a state where the substrate 4075 is fixed. In either case, there are actually halves that are not shown in line symmetry with respect to the center line 4060, but in the figure, halves are shown so that both states can be seen.
[0115]
On the right side of the center line 4060 indicating the state during loading / unloading, the substrate 4076 is floated from the substrate support 4070 by the pusher pins 4072. Further, the substrate fixing device 4074 moves in conjunction with the pusher pin 4072 so that the substrate 4076 is not fixed and the substrate 4076 becomes movable.
[0116]
On the left side of the center line 4060 indicating the state in which the substrate 4075 is fixed, the pusher pin 4071 is accommodated in the substrate support base 4070, and in conjunction with the pusher pin 4071, the substrate fixing device 4073 attaches the substrate 4075 to the substrate support base 4070. Fix so that it is in close contact.
[0117]
Although not shown, a heater that can heat the substrate 4070 is embedded in the substrate support base 4070. A high frequency power source 4080 for applying a high frequency bias is connected to the substrate support 4070 through a matching unit 4081. The matching unit 4081 contains a blocking capacitor, and a high frequency bias is applied to the substrate 4070 by a self-bias applied to the blocking capacitor.
[0118]
A solenoid coil 4020 for generating a magnetic field is installed around the cavity resonance chamber 4030. By applying a direct current to the solenoid coil 4020, a high-density plasma region is created in the cavity resonance chamber 4030 by a microwave and a magnetic field. When a 2.45 GHz microwave is introduced from the waveguide 4001, a high-density plasma region can be created in the cavity resonance plasma region 4040 by generating a magnetic field of 875 Gauss by a solenoid coil.
[0119]
Around the taper chamber 4032, diffusion magnets 4021 and 4022 for plasma diffusion are arranged. The diffusion magnets 4021 and 4022 are used for the purpose, either permanent magnets or electromagnets. Even in the case of an electromagnet, it is not always necessary to be coiled.
[0120]
The gas is introduced by top pipes 4001 and 4011 introduced into the cavity resonance chamber 4030, a taper pipe 4012 introduced into the taper chamber 4032, and 4013 introduced into the reaction chamber 4033. Reaction using microwave and magnetic field has a reaction pressure of 10 ^-1 Since it is as low as Pa or less, there is little need to make the gas flow very strict.
[0121]
In order to remove carbon contaminants adhering to the surface of the substrate 4075, oxygen is first introduced from the top pipe 4001 into the cavity resonance chamber 4030. Pressure is 10 ^-3 -10 ^-1 Set to about Pa. In this embodiment, 3 × 10 ^-2 Performed at Pa. A direct current is passed through the solenoid coil 4020 and a current value of 875 Gauss is measured in the cavity resonance plasma region 4040 in advance, and the current value is passed. The microwave introduced 2.45 GHz from the waveguide 4001. As the microwave power, 500 to 2000 W was introduced, and in this embodiment, 1200 W was introduced. As the substrate 4075, a silicon wafer, a semiconductor such as gallium arsenide, or an insulator such as glass or quartz is used. In this embodiment, an 8-inch silicon wafer is used.
[0122]
High-density plasma with high electron density is generated in the cavity resonance plasma region 4040 by the microwave and the magnetic field generated by the solenoid coil 4020. In the high density plasma, oxygen partially changes to oxygen ions, oxygen radicals, and ozone. Active oxygen such as oxygen ions, oxygen radicals, and ozone reaches the surface of the substrate 4075 along the diffusion magnetic field of the solenoid coil 4020.
[0123]
When the substrate is not as large as a silicon wafer having a diameter of 4 inches compared to the diameter of the cavity resonance chamber 4030 or the opening of the reflection plate 4031, the substrate reaches the substrate 4075 due to the diffusion magnetic field generated by the solenoid coil 4020. Oxygen can sufficiently remove carbon contaminants excluding carbon single bonds. However, when an 8-inch φ silicon wafer is used as the substrate 4075 as in this embodiment, active oxygen generated in the cavity resonance plasma region 4040 is sufficiently removed to sufficiently remove the end of the 8-inch φ wafer. In order to widen the range, diffusion magnets 4021 and 4022 disposed in the taper chamber 4032 are used.
[0124]
The diffusing magnets 4021 and 4022 set the magnetic field so that the magnetic field gradually changes as it gradually approaches the substrate 4075 so that the plasma reaches the substrate 4075 uniformly. As a result, the magnetic field that changes rapidly only by the magnetic field of the solenoid coil 4020 does not change greatly, but changes slowly and produces more uniform active oxygen on the substrate 4075 than in the case of the solenoid coil 4020 alone, in the tapered plasma region 4051. Can do.
[0125]
Further, in the case where some spatter may be present on the substrate 4075, a substrate bias is applied to the substrate holding table 4070 by the high frequency power source 4080. Since oxygen ions are negative, a bias is applied so that the substrate holder 4070 becomes an anode. Thereby, the surface of the substrate 4075 is struck by oxygen ions in the substrate plasma region 3042, thereby making it easier to remove carbon contaminants.
[0126]
Oxygen can be converted to active oxygen using ECR, thereby removing carbon contaminants that remove carbon single bonds such as C—C.
[0127]
Next, hydrogen is first introduced into the cavity resonance chamber 4030 from the top pipe 4001 in order to remove contaminants including single carbon bonds attached to the surface of the substrate 4075. Pressure is 10 ^-3 -10 ^-1 Set to about Pa. In this embodiment, 3 × 10 ^-2 Performed at Pa. A direct current is passed through the solenoid coil 4020 and a current value of 875 Gauss is measured in the cavity resonance plasma region 4040 in advance, and the current value is passed. The microwave introduced 2.45 GHz from the waveguide 4001. As the microwave power, 500 to 2000 W was introduced, and in this embodiment, 1200 W was introduced. As the substrate 4075, a silicon wafer, a semiconductor such as gallium arsenide, or an insulator such as glass or quartz is used. In this embodiment, an 8-inch silicon wafer is used.
[0128]
High-density plasma with high electron density is generated in the cavity resonance plasma region 4040 by the microwave and the magnetic field generated by the solenoid coil 4020. In the high-density plasma, hydrogen partially changes to hydrogen ions or hydrogen radicals. Active hydrogen such as hydrogen ions and hydrogen radicals reaches the surface of the substrate 4075 so as to follow the diffusion magnetic field of the solenoid coil 4020.
[0129]
When the substrate is not as large as a silicon wafer having a diameter of 4 inches compared to the diameter of the cavity resonance chamber 4030 or the opening of the reflection plate 4031, the substrate reaches the substrate 4075 due to the diffusion magnetic field generated by the solenoid coil 4020. Hydrogen can sufficiently remove carbon contaminants containing carbon single bonds. However, when an 8-inch φ silicon wafer is used as the substrate 4075 as in this embodiment, active hydrogen generated in the cavity resonance plasma region 4040 is sufficiently removed in order to sufficiently remove the end of the 8-inch φ wafer. In order to widen the range, diffusion magnets 4021 and 4022 disposed in the taper chamber 4032 are used.
[0130]
The diffusing magnets 4021 and 4022 set the magnetic field so that the magnetic field gradually changes as it gradually approaches the substrate 4075 so that the plasma reaches the substrate 4075 uniformly. As a result, the magnetic field that changes rapidly only by the magnetic field of the solenoid coil 4020 does not change greatly, but changes slowly and produces more uniform active hydrogen on the substrate 4075 than in the case of only the solenoid coil 4020 in the tapered plasma region 4041. Can do.
[0131]
Further, in the case where some spatter may be present on the substrate 4075, a substrate bias is applied to the substrate holding table 4070 by the high frequency power source 4080. Since hydrogen ions are positive, a bias is applied so that the substrate holder 4070 becomes a cathode. Accordingly, the surface of the substrate 4070 is struck by hydrogen ions in the substrate plasma region 4042, thereby making it easier to remove carbon contaminants.
[0132]
Hydrogen can be converted to active hydrogen using microwaves and magnetic fields, thereby removing carbon contaminants containing carbon single bonds such as C—C.
[0133]
Using this device, hydrogen and oxygen can be introduced simultaneously from the top pipe 4010 or separately from the top pipes 4010 and 4011 to simultaneously remove carbon contaminants containing both single and double bonds. It is. In this case, since the polarities of hydrogen ions and oxygen ions are different from positive and negative, the effect of hitting the substrate only with respect to either one of the ions by high frequency substrate bias can be obtained.
[0134]
Instead of introducing hydrogen and oxygen simultaneously, hydrogen and oxygen may be simultaneously cleaned by heating a tank containing water and introducing water vaporized from the vapor pressure into the chamber. In this case, the entire chamber, that is, the cavity resonance chamber 4030, the taper chamber 4032, the reaction chamber 4033, and the piping to the chamber into which water is introduced are all heated. The heating temperature is required to be about 60 to 400 ° C. In this embodiment, since many Viton O-rings are used for vacuum packing, heating is performed at 150 ° C.
[0135]
With such an apparatus, when an 8-inch silicon wafer is cleaned, a substrate having a clean surface as shown in graph 13 of FIG. 1 can be obtained.
[0136]
Further, when such an apparatus is used, since there is no reflector like between the cavity resonance chamber 4030 and the taper chamber 4032, the traveling wave of the microwave further advances to the vicinity of the substrate 4075. Therefore, the diffusion magnet 4032 makes it possible to satisfy the ECR condition even in a region such as the taper plasma region 4051 and the substrate plasma region 4042.
[0137]
Therefore, active hydrogen or active acid activated at a high plasma density can reach the substrate surface while the active state is higher than that activated in the cavity resonance laser region 4040. Of course, since the plasma having such a high plasma density is generated in the vicinity of the substrate, the substrate is also exposed to the plasma, and therefore, the substrate needs to be hardly damaged by plasma.
[0138]
Example 3
FIG. 6 shows another embodiment of the present invention. FIG. 6 shows a case where the apparatus shown in Example 2 is used as a multi-chamber system. The drawing shows a longitudinal section of the device. The left side of the figure shows the same device as that described in the second embodiment. The apparatus shown on the left side is an apparatus 6000 using a microwave and a magnetic field, and the contents thereof are as shown in the second embodiment.
[0139]
A device 6000 using a microwave and a magnetic field is connected to a connection chamber 6001. This connection chamber 6001 is further connected to the processing apparatus 6100. The connection chamber 6001 may be connected to a process apparatus other than the apparatus 6000 and the processing apparatus 6100 using a microwave and a magnetic field. That is, the connection chamber 6001 can also serve as a common chamber for each process apparatus.
[0140]
There is a transfer robot 6002 in the connection chamber 6001, and an object to be processed is unloaded from the apparatus using the microwave and the magnetic field while the gate 6003 is opened from the apparatus 6000 using the microwave and the magnetic field, or vice versa. Can do. When the loading / unloading is completed, the gate 6003 is closed. In an apparatus 6000 using a microwave and a magnetic field, the object to be processed is cleaned to reduce carbon contaminants including carbon single bonds or double bonds, and then the apparatus 6000 using a microwave and a magnetic field is used. The remaining gas is exhausted. After that, the gate 6003 is opened and the object to be processed is moved into the connection chamber 6001 by the transfer robot 6002. After the workpiece is completely moved into the connection chamber 6001 and the gate 6003 can be closed, the gate 6003 is closed.
[0141]
Although the connection chamber 6001 is not illustrated, the connection chamber 6001 is connected to a vacuum pump capable of reducing the pressure in the connection chamber 6001, and is always in a reduced pressure state when the workpiece is transported. For reducing the pressure in the connection chamber 6001, a dry pump system with little contamination is preferable, and a combination of a turbo pump and a dry pump is preferable. In this embodiment, evacuation can be performed by a combination of a magnetic levitation turbomolecular pump and a dry pump.
[0142]
In order to reduce the influence of contamination from other process devices, the connection chamber 6001 is also effective to make the gas flow from the connection chamber 6001 to the process device slightly higher than the process device. .
[0143]
After the object to be processed is carried into the connection chamber 6001, the gate 6004 is opened and the object to be processed is moved to the processing apparatus 6100. After the workpiece is moved to the processing apparatus 6100, the gate 6004 is closed.
[0144]
The processing apparatus 6100 is a parallel plate type plasma CVD apparatus, and a pump 613 is connected to a reaction chamber 6010 through a pump valve 6011 and a conductance controller 6012. An exhaust 6014 is further connected to the pump 6013. The connection order of the pump valve 6011 and the conductance controller 6012 may be reversed.
[0145]
An electrode 6040 is connected to the reaction chamber 6010 with an insulator 6042 that separates from the ground potential of the chamber, and an electrode cover 6041 is provided to cover the electrode 6040 to prevent parasitic discharge and hollow cathode. Has been. A plasma power source 6044 is connected to the electrode 6040 through a matching unit 6043.
[0146]
As the plasma power supply 6044, a continuous oscillator from a low frequency to a high frequency, a pulse oscillator, a modulation oscillator, or the like is used depending on the purpose of film formation. In this embodiment, a power source capable of pulse oscillation of 20 MHz is used.
[0147]
There is a means for holding the substrate in the reaction chamber 6010. The left side of the center line 6020 represents the position when the substrate 6036 is carried out or carried in. The right side of the center line 6020 represents a state where the substrate 6035 is fixed. In both cases, there are actually halves that are not shown in line symmetry with respect to the center line 6020, but in the figure, halves are shown so that both states can be seen.
[0148]
On the left side of the center line 6020 indicating the state during loading / unloading, the substrate 6036 is lifted from the substrate support 6030 by the pusher pin 6032. Further, the substrate fixing device 6034 moves in conjunction with the pusher pin 6032 so that the substrate 6036 is not fixed and the substrate 6036 becomes movable.
[0149]
On the right side of the center line 6020 indicating the state in which the substrate 6035 is fixed, the pusher pin 6031 is accommodated in the substrate support 6030, and the substrate fixture 6033 interlocks with the pusher pin 6031 and the substrate 6035 is attached to the substrate support 6030. Fix so that it is in close contact.
[0150]
Although not shown, a heater that can heat the substrate 6035 is embedded in the substrate support 6030. The gas is introduced from the introduction pipe 6050 through the shower head of the electrode 6040 through a flow controller such as a mass flow controller. The electrode 6040 is provided with a diffusion plate (not shown) for flowing gas uniformly.
[0151]
P as substrate 6035 ^- A silicon oxide film was formed with organosilane and oxygen immediately after the surface of the substrate 6035 was cleaned with an apparatus 6000 using a microwave and a magnetic field using an 8-inch single crystal silicon wafer of 100 surfaces. As the film formation conditions, tetraethyl silicate (so-called TEOS) is used as the organic silane, the film ratio is TEOS / oxygen = 1/20, the substrate temperature is 350 ° C., and the pressure is 1 Torr. And the interface state density was measured to be 9 × 10 ⁹ ~ 3x10 ^Ten cm ^-2 eV ^-1 And it was good.
[0152]
Example 4
FIG. 7 shows an apparatus for carrying out the present invention. The figure shows the configuration of the longitudinal section of the apparatus. A microwave waveguide 7001 is connected to the reaction chamber 7030 so as to cover the microwave introduction window 7002. For the introduction window 7002, quartz, synthetic quartz, magnesium fluoride, or the like is used, but synthetic quartz is used in this embodiment.
[0153]
The reaction chamber 7030 is connected to a pump 7036 via a pump valve 7034 and a conductance regulator 7035. The pump 7036 exhausts unnecessary gas or the like to the exhaust pipe 7037. The connection order of the pump valve 7034 and the conductance adjuster 7035 may be reversed. The pressure in the reaction chamber 7030 is controlled by a conductance regulator 7035 and a pump valve 7034. As the pump 7036, a turbo molecular pump, a complex molecular pump, an oil diffusion pump, or the like is used. Although not shown, these pumps are used by connecting an auxiliary pump such as an oil rotary pump to the exhaust side of the pump. In this example, a dry pump was used as the composite turbo molecular pump and the auxiliary pump.
[0154]
In the reaction chamber 7030, a movable gate valve 7050 is connected to another decompression chamber 7054. Here, it is needless to say that it is not connected to another decompression chamber 7054 and may be used as a single device. The gate valve 7050 is a slide type valve. Here, the gate valve 7050 may be opened in an open state with a hinge or the like as an axis.
[0155]
There is a means for holding the substrate in the reaction chamber 7030. The right side of the center line 7060 represents the position when the substrate 7076 is unloaded or loaded. The left side of the center line 7060 represents a state where the substrate 7075 is fixed. In either case, there are actually halves that are not shown in line symmetry with respect to the center line 7060, but in the figure, halves are shown so that both states can be seen.
[0156]
On the right side of the center line 7060 indicating the state during loading / unloading, the substrate 7076 is floated from the substrate support 7070 by pusher pins 7072. Further, the substrate fixing device 7074 moves in conjunction with the pusher pin 7072 so that the substrate 7076 is not fixed and the substrate 7076 becomes movable.
[0157]
On the left side of the center line 7060 indicating the state in which the substrate 7075 is fixed, the pusher pin 7071 is accommodated in the substrate support 7070, and in conjunction with the pusher pin 7071, the substrate fixing device 7073 attaches the substrate 7075 to the substrate support 7070. Fix so that it is in close contact.
[0158]
Although not shown, a heater that can heat the substrate 7070 is embedded in the substrate support 7070. A high frequency power source 7080 for applying a high frequency bias is connected to the substrate support 7070 through a matching unit 7081. The matching unit 7081 contains a blocking capacitor, and a high frequency bias is applied to the substrate 7070 by a self-bias applied to the blocking capacitor.
[0159]
A split coil 7020 for generating a magnetic field is installed around the reaction chamber 7030. By supplying a direct current to the split coil 7020, a magnetic field necessary for electron cyclotron resonance is generated in the reaction chamber 7030. When a 2.45 GHz microwave is introduced from the waveguide 7001, an ECR condition can be created as a high-density plasma region by generating a magnetic field of 875 Gauss with a coil.
[0160]
Since each of the divided coils 7020 can flow an electric current independently, a plurality of regions satisfying high-density plasma such as ECR conditions can be formed in the reaction chamber 7030. It is also possible to move the spatial position satisfying high-density plasma such as ECR conditions to various positions. Therefore, it is suitable for processing a large substrate.
[0161]
Diffusion magnets 7021 and 7022 for plasma diffusion are arranged. The diffusing magnets 7021 and 7022 are used in accordance with their purposes, whether permanent magnets or electromagnets. Even in the case of an electromagnet, it is not always necessary to be coiled.
[0162]
The gas is introduced by a top pipe 7001 introduced into the reaction chamber 7030 and 7013 introduced into the reaction chamber 7030. Reaction using microwave and magnetic field has a reaction pressure of 10 ^-1 Since it is as low as Pa or less, there is little need to make the gas flow very strict.
[0163]
In order to remove carbon contaminants attached to the surface of the substrate 7075, oxygen is first introduced into the reaction chamber 7030 from the top pipe 7001. Pressure is 10 ^-3 -10 ^-1 Set to about Pa. In this embodiment, 3 × 10 ^-2 Performed at Pa. A direct current is passed through the split coil 7020 to measure in advance a current value of 875 Gauss at a desired spatial position, and the current value is passed. The microwave introduced 2.45 GHz from the waveguide 7001. As the microwave power, 500 to 2000 W was introduced, and in this embodiment, 1500 W was introduced. As the substrate 7075, a semiconductor such as a silicon wafer or gallium arsenide, or an insulator such as glass or quartz is used. In this embodiment, borosilicate glass having a thickness of 360 mm × 480 mm and a thickness of 0.7 mm is used.
[0164]
High-density plasma with high electron density is generated by achieving high-density plasma such as ECR conditions by the microwave and the magnetic field generated by the split coil 7020. In high density plasma such as ECR, oxygen partially changes to oxygen ions, oxygen radicals, and ozone. Active oxygen such as oxygen ions, oxygen radicals, and ozone reaches the substrate 7075 along a magnetic field that is independently generated by the split coil 7020. Alternatively, the ECR spatial region may be moved within the reaction chamber 7030.
[0165]
When the substrate is not as large as the diameter of the reaction chamber 7030, for example, a silicon wafer having a diameter of 4 inches, a single bond of carbon is removed by active oxygen reaching the substrate 7075 by the magnetic field generated by the split coil 7020. Carbon contaminants can be removed sufficiently. However, when a borosilicate glass having a thickness of 360 mm × 480 mm and a thickness of 0.7 mm is used as the substrate 7075 as in this embodiment, in order to sufficiently remove the edge of the glass, in order to spread active oxygen over a wide range. , Diffusion magnets 7021 and 7022 are used.
[0166]
The diffusion magnets 7021 and 7022 are set so that the magnetic field gradually changes as the magnetic field gradually approaches the substrate 7075 so that the plasma reaches the substrate 7075 uniformly. As a result, in addition to the control of the split coil 7020 only by the magnetic field, the change gradually changes, and more uniform active oxygen can be produced on the substrate 7075 than on the split coil 7020 alone.
[0167]
Further, in the case where there may be some sputtering on the substrate 7075, a substrate bias is applied to the substrate holding table 7070 by the high frequency power source 7080. Since oxygen ions are negative, a bias is applied so that the substrate holder 7070 becomes an anode. Accordingly, the surface of the substrate 7070 is hit with oxygen ions, so that carbon contaminants can be more easily removed.
[0168]
Oxygen can be converted to active oxygen using ECR, thereby removing carbon contaminants that remove carbon single bonds such as C—C.
[0169]
Next, hydrogen is first introduced into the reaction chamber 7030 from the top pipe 7001 in order to remove contaminants including a single bond of carbon attached to the surface of the substrate 7075. Pressure is 10 ^-3 -10 ^-1 Set to about Pa. In this embodiment, 3 × 10 ^-2 Performed at Pa. A direct current is passed through the split coil 7020 and a current value of 875 Gauss is measured in advance, and the current value is passed. The microwave introduced 2.45 GHz from the waveguide 7001. As the microwave power, 500 to 2000 W was introduced, and in this embodiment, 1200 W was introduced. As the substrate 7075, a semiconductor such as a silicon wafer or gallium arsenide, or an insulator such as glass or quartz is used. In this embodiment, borosilicate glass having a thickness of 360 mm × 480 mm and a thickness of 0.7 mm is used.
[0170]
High-density plasma with high electron density is generated by achieving high-density plasma such as ECR conditions by the microwave and the magnetic field generated by the split coil 7020. In high-density plasma such as ECR plasma, part of hydrogen changes to hydrogen ions or hydrogen radicals. Active hydrogen such as hydrogen ions and hydrogen radicals reaches the substrate 7075 along a magnetic field generated independently by the split coil 7020. In addition, the spatial region of the high-density plasma region may be moved in the reaction chamber 7030.
[0171]
If the substrate is not large compared to the diameter of the reaction chamber 7030, for example, a silicon wafer having a diameter of 4 inches, it contains a single bond of carbon due to active hydrogen reaching the substrate 7075 by the diffusion magnetic field created by the split coil 7020. Carbon contaminants can be removed sufficiently. However, when a borosilicate glass having a size of 360 mm × 480 mm and a thickness of 0.7 mm is used as the substrate 7075 as in this embodiment, diffusion magnets 7021 and 7022 are used in order to sufficiently remove the edge of the glass.
[0172]
The diffusion magnets 7021 and 7022 are set so that the magnetic field gradually changes as the magnetic field gradually approaches the substrate 7075 so that the plasma reaches the substrate 7075 uniformly. As a result, in addition to the control of the split coil 7020 only by the magnetic field, the change gradually changes, and more uniform active oxygen can be produced on the substrate 7075 than on the split coil 7020 alone.
[0173]
Further, in the case where there may be some sputtering on the substrate 7075, a substrate bias is applied to the substrate holding table 7070 by the high frequency power source 7080. Since hydrogen ions are positive, a bias is applied so that the substrate holder 7070 becomes a cathode. Thereby, the surface of the substrate 7070 is struck by hydrogen ions in the substrate plasma region 7042, thereby making it easier to remove carbon contaminants.
[0174]
Hydrogen can be converted to active hydrogen using microwaves and magnetic fields, thereby removing carbon contaminants containing carbon single bonds such as C—C.
[0175]
Using this apparatus, it is also possible to introduce hydrogen and oxygen from the top pipe 7010 at the same time, and simultaneously remove carbon contaminants containing both single and double bonds. In this case, since the polarities of hydrogen ions and oxygen ions are different from positive and negative, the effect of hitting the substrate only with respect to either one of the ions by high frequency substrate bias can be obtained.
[0176]
Instead of introducing hydrogen and oxygen simultaneously, hydrogen and oxygen may be simultaneously cleaned by heating a tank containing water and introducing water vaporized from the vapor pressure into the chamber. In this case, the entire chamber, that is, the reaction chamber 7030 and all the piping to the chamber into which water is introduced are heated. The heating temperature is required to be about 60 to 400 ° C. In this embodiment, since many Viton O-rings are used for vacuum packing, heating is performed at 150 ° C.
[0177]
When the substrate was cleaned with 360 mm × 480 mm 0.7 mm thick borosilicate glass by such an apparatus, the carbon contamination on the surface of the substrate as seen from the contact angle of contact water was remarkably improved as compared with before cleaning.
[0178]
Example 5
FIG. 8 shows another embodiment of the present invention. FIG. 8 shows a case where the apparatus shown in Example 4 is used as a multi-chamber system. The drawing shows a longitudinal section of the device. The left side of the figure shows the same device as that described in the fourth embodiment. The apparatus shown on the left side is an apparatus 8000 using a microwave and a magnetic field, and the contents thereof are as shown in the fourth embodiment.
[0179]
A microwave and magnetic field utilizing device 8000 is connected to a connection chamber 8001. This connection chamber 8001 is further connected to a processing apparatus 8100. The connection chamber 8001 may be connected to a process device other than the microwave and magnetic field utilizing device 8000 and the processing device 8100. That is, the connection chamber 8001 can also serve as a common chamber for each process apparatus.
[0180]
There is a transfer robot 8002 in the connection chamber 8001, and the object to be processed can be carried out of the apparatus using the microwave and the magnetic field from the apparatus 8000 using the microwave and the magnetic field, or vice versa. . When the loading / unloading is completed, the gate 8003 is closed. In the microwave and magnetic field device 8000, the object to be processed is cleaned to reduce carbon contaminants containing single or double carbon bonds, and then remain in the microwave and magnetic field device 8000. Exhaust the gas. After that, the gate 8003 is opened and the workpiece is moved into the connection chamber 8001 by the transfer robot 8002. After the workpiece is completely moved into the connection chamber 8001 and the gate 8003 can be closed, the gate 8003 is closed.
[0181]
Although the connection chamber 8001 is not illustrated, the connection chamber 8001 is connected to a vacuum pump capable of reducing the pressure in the connection chamber 8001, and is always in a reduced pressure state when the workpiece is transferred. For the decompression of the connection chamber 8001, a dry pump system with little contamination is preferable, and a combination of a turbo pump and a dry pump is preferable. In this embodiment, evacuation can be performed by a combination of a magnetic levitation turbomolecular pump and a dry pump.
[0182]
In order to reduce the influence of contamination from other process apparatuses, the connection chamber 8001 is also slightly higher in pressure than the process apparatus so that a gas flow can flow from the connection chamber 8001 to the process apparatus. .
[0183]
After the workpiece is carried into the connection chamber 8001, the gate 8004 is opened and the workpiece is moved to the processing apparatus 8100. After the workpiece is moved to the processing apparatus 8100, the gate 8004 is closed.
[0184]
The processing apparatus 8100 is a parallel plate type plasma CVD apparatus, and a pump 8013 is connected to a reaction chamber 8010 through a pump valve 8011 and a conductance controller 8012. An exhaust 8014 is further connected to the pump 8013. The connection order of the pump valve 8011 and the conductance controller 8012 may be reversed.
[0185]
An electrode 8040 is connected to the reaction chamber 8010 with an insulator 8042 that separates from the ground potential of the chamber, and an electrode cover 8041 is installed so as to cover the electrode 8040 to prevent parasitic discharge and hollow cathode. ing. A plasma power source 8044 is connected to the electrode 8040 through a matching unit 8043.
[0186]
As the plasma power source 8044, a continuous oscillator from a low frequency to a high frequency, a pulse oscillator, a modulation oscillator, or the like is used depending on the purpose of film formation. In this embodiment, a power source capable of pulse oscillation of 20 MHz is used.
[0187]
There is a means for holding the substrate in the reaction chamber 8010. The left side of the center line 8020 represents the position when the substrate 8036 is carried out or carried in. The right side of the center line 8020 represents a state where the substrate 8035 is fixed. In either case, there are actually halves that are not shown in line symmetry with respect to the center line 8020, but in the figure, both halves are shown so that both states can be seen.
[0188]
On the left side of the center line 8020 indicating the state during loading / unloading, the substrate 8036 is lifted from the substrate support 8030 by the pusher pin 8032. Further, the substrate fixing device 8034 moves in conjunction with the pusher pin 8032 so that the substrate 8036 is not fixed and the substrate 8036 becomes movable.
[0189]
On the right side of the center line 8020 indicating the state in which the substrate 8035 is fixed, the pusher pin 8031 is accommodated in the substrate support base 8030, and in conjunction with the pusher pin 8031, the substrate fixer 8033 attaches the substrate 8035 to the substrate support base 8030. Fix so that it is in close contact.
[0190]
Although not shown, a heater that can heat the substrate 8035 is embedded in the substrate support base 8030. The gas is introduced from the introduction pipe 8050 through the shower head of the electrode 8040 through a flow controller such as a mass flow controller. The electrode 8040 is provided with a diffusion plate (not shown) for flowing gas uniformly.
[0191]
P as substrate 8035 ^- A silicon oxide film was formed with organosilane and oxygen immediately after the surface of the substrate 8035 was cleaned with an apparatus 8000 using a microwave and a magnetic field, using the (100) plane 8-inch single crystal silicon wafer. As the film formation conditions, tetraethyl silicate (so-called TEOS) is used as the organic silane, the film ratio is TEOS / oxygen = 1/20, the substrate temperature is 350 ° C., and the pressure is 1 Torr. And the interface state density was measured to be 9 × 10 ⁹ ~ 3x10 ^Ten cm ^-2 eV ^-1 And it was good.
[0192]
Example 6
FIG. 9 shows an apparatus for carrying out the present invention. FIG. 9 shows a configuration diagram of a longitudinal section of the apparatus. A microwave waveguide 9001 serves as a microwave inlet, and the antenna 9003 has a structure in which a rigidano coil is expanded in a disk shape. A slit 9004 opened in the antenna 9003 is a so-called one-stroke drawing. The introduction window 9002 is connected to the reaction chamber 9030. As the introduction window 9002, quartz, synthetic quartz, magnesium fluoride, or the like is used, but synthetic quartz is used in this embodiment. A permanent magnet 9005 is provided above the slit 9004, and an electric field generated in the slit 9004 generates a plasma 9040 by a microwave and a magnetic field on the path of the slit 9004.
[0193]
The reaction chamber 9030 is connected to a pump 9036 via a pump valve 9034 and a conductance regulator 9035. The pump 9036 exhausts unnecessary gas and the like to the exhaust pipe 9037. The connection order of the pump valve 9034 and the conductance adjuster 9035 may be reversed. The pressure in the reaction chamber 9030 is controlled by a conductance regulator 9035 and a pump valve 9034. As the pump 9036, a turbo molecular pump, a complex molecular pump, an oil diffusion pump, or the like is used. Although not shown, these pumps are used by connecting an auxiliary pump such as an oil rotary pump to the exhaust side of the pump. In this example, a dry pump was used as the composite turbo molecular pump and the auxiliary pump.
[0194]
The reaction chamber 9030 is connected to another decompression chamber 9054 through a movable gate valve 9050. Here, it is of course possible to use as a single device without being connected to another decompression chamber 9054. The gate valve 9050 is a slide type valve. Here, the gate valve 9050 may be opened in an open state with a hinge or the like as an axis.
[0195]
There is a means for holding the substrate in the reaction chamber 9030. The right side of the center line 9060 represents the position when the substrate 9076 is carried out or carried in. The left side of the center line 9060 represents a state where the substrate 9075 is fixed. In either case, there are actually halves that are not shown in line symmetry with respect to the center line 9060, but in the figure, both halves are shown so that both states can be seen.
[0196]
On the right side of the center line 9060 indicating the state during loading / unloading, the substrate 9076 is lifted from the substrate support 9070 by the pusher pin 9072. Further, the substrate fixing device 9074 moves in conjunction with the pusher pin 9072 so that the substrate 9076 is unfixed and the substrate 9076 becomes movable.
[0197]
On the left side of the center line 9060 indicating the state in which the substrate 9075 is fixed, the pusher pin 9071 is accommodated in the substrate support table 9070, and in conjunction with the pusher pin 9071, the substrate fixing device 9073 holds the substrate 9075 on the substrate support table 9070. Fix so that it is in close contact.
[0198]
Although not shown, a heater that can heat the substrate 9070 is embedded in the substrate support 9070. A high frequency power source 9080 for applying a high frequency bias is connected to the substrate support 9070 through a matching unit 9081. The matching unit 9081 contains a blocking capacitor, and a high frequency bias is applied to the substrate 9070 by a self-bias applied to the blocking capacitor.
[0199]
A permanent magnet 9005 for generating a magnetic field is provided around the reaction chamber 9030. A magnetic field necessary for electron cyclotron resonance is generated in the reaction chamber 9030 by the magnetic field of the permanent magnet 9005. When a 2.45 GHz microwave is introduced from the waveguide 9001, a high-density plasma condition such as ECR can be created by generating a magnetic field of 875 Gauss with a permanent magnet 9005.
[0200]
The gas is introduced through a pipe 9001 introduced into the reaction chamber 9030. Reaction using high-density plasma such as ECR has a reaction pressure of 10 ^-1 Since it is as low as Pa or less, there is little need to make the gas flow very strict.
[0201]
In order to remove carbon contaminants attached to the surface of the substrate 9075, oxygen is first introduced into the reaction chamber 9030 from the pipe 9001. Pressure is 10 ^-3 -10 ^-1 Set to about Pa. In this embodiment, 3 × 10 ^-2 Performed at Pa. The microwave introduced 2.45 GHz from the waveguide 9001. Microwave power of 500 to 2000 W was introduced, and 800 W was introduced in this example. As the substrate 9075, a semiconductor such as a silicon wafer or gallium arsenide, or an insulator such as glass or quartz is used. In this embodiment, borosilicate glass having a thickness of 360 mm × 480 mm and a thickness of 0.7 mm is used.
[0202]
ECR plasma with high electron density is generated by achieving high-density plasma conditions such as ECR by the magnetic field generated by the microwave and the permanent magnet 9005. In high density plasma such as ECR, oxygen partially changes to oxygen ions, oxygen radicals, and ozone. Active oxygen such as oxygen ions, oxygen radicals, and ozone reaches the substrate 9075.
[0203]
Further, in the case where a slight amount of spatter may be present on the substrate 9075, a substrate bias is applied to the substrate holder 9070 by the high frequency power source 9080. Since oxygen ions are negative, a bias is applied so that the substrate holder 9070 becomes an anode. Accordingly, the surface of the substrate 9070 is hit with oxygen ions, so that carbon contaminants can be more easily removed.
[0204]
Oxygen can be converted to active oxygen using microwaves and magnetic fields such as ECR, thereby removing carbon contaminants except carbon single bonds such as C—C.
[0205]
Next, hydrogen is first introduced into the reaction chamber 9030 from the pipe 9001 in order to remove a contaminant including a single bond of carbon attached to the surface of the substrate 7075. Pressure is 10 ^-3 -10 ^-1 Set to about Pa. In this embodiment, 3 × 10 ^-2 Performed at Pa. The microwave introduced 2.45 GHz from the waveguide 9001. Microwave power of 500 to 2000 W was introduced, and 800 W was introduced in this example. As the substrate 9075, a semiconductor such as a silicon wafer or gallium arsenide, or an insulator such as glass or quartz is used. In this embodiment, borosilicate glass having a thickness of 360 mm × 480 mm and a thickness of 0.7 mm is used.
[0206]
High-density plasma such as ECR having a high electron density is generated by achieving conditions of high-density plasma such as ECR by the magnetic field generated by the microwave and the permanent magnet 9005. In high density plasma such as ECR, part of hydrogen changes to hydrogen ions or hydrogen radicals. Active hydrogen such as hydrogen ions and hydrogen radicals reaches the substrate 9075.
[0207]
Further, in the case where a slight amount of spatter may be present on the substrate 9075, a substrate bias is applied to the substrate holder 9070 by the high frequency power source 9080. Since hydrogen ions are positive, a bias is applied so that the substrate holder 9070 becomes a cathode. As a result, the surface of the substrate 9070 is hit with hydrogen ions, thereby making it easier to remove carbon contaminants.
[0208]
Oxygen can be converted to active hydrogen using microwaves and magnetic fields such as ECR, thereby removing carbon contaminants that remove carbon single bonds such as C—C.
[0209]
Example 7
FIG. 10 shows another embodiment of the present invention. FIG. 10 shows a case where the apparatus shown in Example 6 is used as a multi-chamber system. The drawing shows a longitudinal section of the device. The left side of the figure shows the same device as that described in the fourth embodiment. The apparatus shown on the left side is an apparatus 10000 using a microwave and a magnetic field, and the contents thereof are as shown in the sixth embodiment.
[0210]
A microwave and magnetic field utilization device 10000 is connected to a connection chamber 10001. This connection chamber 10001 is further connected to the processing apparatus 10100. The connection chamber 10001 may be connected to a process device other than the microwave and magnetic field using device 10000 and the processing device 10100. That is, the connection chamber 10001 can also function as a common chamber for each process apparatus.
[0211]
There is a transfer robot 10002 in the connection chamber 10001, and the object to be processed can be carried out from the apparatus using the microwave and the magnetic field while the gate 10003 is opened from the apparatus 10000 using the microwave and the magnetic field, or vice versa. . When the loading / unloading is completed, the gate 10003 is closed. The object to be processed is cleaned in the microwave and magnetic field device 10000 to reduce carbon contaminants containing single or double carbon bonds, and then remains in the microwave and magnetic field device 10000. Exhaust the gas. After that, the gate 10003 is opened, and the object to be processed is moved into the connection chamber 10001 by the transfer robot 10002. After the workpiece is completely moved into the connection chamber 10001 and the gate 10003 can be closed, the gate 10003 is closed.
[0212]
A vacuum pump (not shown) that can reduce the pressure in the connection chamber 10001 is connected to the connection chamber 10001 so that the connection chamber 10001 is always in a reduced pressure state when the workpiece is transferred. For the decompression of the connection chamber 10001, a dry pump system with little contamination is preferable, and a combination of a turbo pump and a dry pump is preferable. In this embodiment, evacuation can be performed by a combination of a magnetic levitation turbomolecular pump and a dry pump.
[0213]
In order to reduce the influence of contamination from other process apparatuses, the connection chamber 10001 is also effective to make the gas flow from the connection chamber 10001 to the process apparatus slightly higher than the process apparatus. .
[0214]
After the object to be processed is carried into the connection chamber 10001, the gate 10004 is opened and the object to be processed is moved to the processing apparatus 10100. After the workpiece is moved to the processing apparatus 10100, the gate 10004 is closed.
[0215]
The processing apparatus 10100 is a parallel plate type plasma CVD apparatus, and a pump 10013 is connected to a reaction chamber 10010 through a pump valve 10011 and a conductance controller 10012. An exhaust 10014 is further connected to the pump 10013. The connection order of the pump valve 10011 and the conductance controller 10012 may be reversed.
[0216]
An electrode 10040 is connected to the reaction chamber 10010 with an insulator 10042 that separates from the ground potential of the chamber, and an electrode cover 10040 is installed to cover the electrode 10040 so as to cover the parasitic discharge and the hollow cathode. ing. A plasma power source 10044 is connected to the electrode 10040 through a matching unit 10043.
[0217]
As the plasma power source 10044, a continuous oscillator from a low frequency to a high frequency, a pulse oscillator, a modulation oscillator, or the like is used depending on the purpose of film formation. In this embodiment, a power source capable of pulse oscillation of 20 MHz is used.
[0218]
There is a means for holding the substrate in the reaction chamber 10010. The left side of the center line 10020 represents the position when the substrate 10036 is unloaded or loaded. The right side of the center line 10020 represents a state in which the substrate 10033 is fixed. In either case, there are actually halves that are not shown in line symmetry with respect to the center line 10020, but in the figure, halves are shown so that both states can be seen.
[0219]
On the left side of the center line 10020 indicating the state during loading / unloading, the substrate 1000036 is lifted from the substrate support 10030 by the pusher pin 10032. Further, the substrate fixing device 10034 also moves in conjunction with the pusher pin 10032 so that the substrate 10036 is not fixed and the substrate 10036 becomes movable.
[0220]
On the right side of the center line 10020 indicating the state in which the substrate 10033 is fixed, the pusher pin 10031 is accommodated in the substrate support base 10030, and the substrate fixing device 10033 interlocks with the pusher pin 10030 and the substrate fixer 10033 attaches the substrate 10033 to the substrate support base 10030. Fix so that it adheres to
[0221]
Although not shown, a heater that can heat the substrate 10033 is embedded in the substrate support 10030. The gas is introduced from the introduction pipe 10050 through the shower head of the electrode 10040 through a flow rate controller such as a mass flow controller. The electrode 10040 is provided with a diffusion plate (not shown) for flowing gas uniformly.
[0222]
P as substrate 10033 ^- A silicon oxide film was formed using organosilane and oxygen immediately after cleaning the surface of the substrate 10033 using a microwave and magnetic field apparatus 10000 using a 100-inch 8-inch single crystal silicon wafer. As the film formation conditions, tetraethyl silicate (so-called TEOS) is used as the organic silane, the film ratio is TEOS / oxygen = 1/20, the substrate temperature is 350 ° C., and the pressure is 1 Torr. And the interface state density was measured to be 9 × 10 ⁹ ~ 3x10 ^Ten cm ^-2 eV ^-1 And it was good.
[0223]
Example 8
FIG. 11 shows a process of forming a thin film transistor on an insulating substrate using the present invention. The insulating substrate 1100 is a carbon containing a single bond of carbon such as C-C and a double bond of carbon such as C = C on the insulating substrate 1100 by using a plasma generated by a microwave and a magnetic field in a multi-chamber. To remove contaminants , First, active oxygen such as oxygen ions, oxygen radicals, and ozone is generated from oxygen using ECR plasma, thereby cleaning the insulating substrate 1100.
[0224]
Since no film is formed on the insulating substrate 1100, there is no influence of the charge in the active oxygen. Therefore, a high frequency bias is applied to the insulating substrate 1100 and sputtering with oxygen ions is performed simultaneously. Remove carbon contaminants containing double bonds. Pressure is 1x10 ^-3 ~ 5x10 ^-Five Torr, but typically 3x10 ^-Four Perform in Torr. Microwave power is 500-2000W, typically 1200W. The substrate temperature is from room temperature to 500 ° C., typically 250 ° C. The flow rate of oxygen is 5 to 200 SCCM, typically 80 SCCM. The substrate bias is 0.05 to 1.0 W / cm as high frequency power. ² Typically 0.3 W / cm ² Apply.
[0225]
After removal of carbon contaminants containing mainly double bonds of carbon with active oxygen, the carbon contaminants containing mainly single bonds of carbon with active hydrogen using microwaves such as ECR and plasma with a magnetic field are removed. Perform removal. Since no film is formed on the insulating substrate 1100, there is no influence of the charge in the active hydrogen. Therefore, a high-frequency bias is applied to the insulating substrate 1100 and sputtering with hydrogen ions is performed simultaneously. Removal of carbon contaminants containing single bonds. Pressure is 1x10 ^-3 ~ 5x10 ^-Five Torr, but typically 5x10 ^-Four Perform in Torr. Microwave power is 500-2000W, typically 1200W. The substrate temperature is from room temperature to 500 ° C., typically 250 ° C. The hydrogen flow rate is 5 to 200 SCCM, typically 80 SCCM. The substrate bias is 0.05 to 1.0 W / cm as high frequency power. ² Typically 0.2W / cm ² Apply.
[0226]
After the carbon cleaning on the insulating substrate 1100 is completed, the base film 1101 is formed without being exposed to the air. As the base film 1101, silicon oxide, nitrogen-doped silicon oxide, phosphorus-doped silicon oxide, silicon nitride, or the like is formed. As a film forming method, low pressure CVD, sputtering, parallel plate plasma CVD, ECR plasma CVD, plasma CVD such as ICP plasma CVD, or the like is used. Typically, parallel plate type plasma CVD is used.
[0227]
The film forming conditions are typically 400 ° C. at a substrate temperature of 300 to 600 ° C. Regular tetraethyl silicate (so-called TEOS): oxygen = 1: 1 to 20, typically 1: 5. The pressure is 0.1 to 2 Torr, and typically 0.3 Torr. The high frequency applied to the parallel plate electrodes is 5 to 30 MHz, typically 13.56 MHz, and the power is 0.05 to 2.0 W / cm. ² Typically 0.7W / cm ² Apply. The thickness of the base film 1101 is 100 to 5000 mm, typically 2000 mm.
[0228]
When the formation of the base film 1101 is completed, amorphous silicon serving as an active layer is formed in another processing chamber of the multi-chamber system without exposure to the atmosphere. As a method for forming the amorphous silicon, low pressure CVD, sputtering, parallel plate plasma CVD, ECR plasma CVD, plasma CVD such as ICP plasma CVD, or the like is used. Typically, parallel plate type plasma CVD is used.
[0229]
In this embodiment, amorphous silicon is deposited using a parallel plate type plasma CVD apparatus. Deposition conditions are typically 300 ° C. at a substrate temperature of 150-600 ° C. SiH as reaction gas _Four 10 to 500 SCCM, typically 55 SCCM is used. The pressure is 0.1 to 2 Torr, and typically 0.75 Torr. The high frequency applied to the parallel plate electrodes is 5 to 30 MHz, typically 13.56 MHz, and the power is 0.01 to 2.0 W / cm. ² Typically 0.05 W / cm ² Apply. The thickness of the amorphous silicon is 100 to 5000 mm, and typically 500 mm is formed.
[0230]
After the amorphous silicon film is formed, the substrate on which the amorphous silicon film is formed on the insulating substrate 1100 is taken out into the atmosphere. Thereafter, hydrogen is extracted before crystallization of amorphous silicon. Hydrogen removal is performed at 400 to 500 ° C. in nitrogen for about 30 minutes to 5 hours, typically at 450 ° C. for 1 hour. Thereafter, thermal crystallization or laser crystallization is performed. Here, thermal crystallization can be performed at a temperature of 600 ° C. or lower by using a method such as JP-A-6-232059 by the present applicants. In this method, a solution containing Ni is applied to grow a crystal using nickel silicide as a nucleus.
[0231]
It is also effective to perform laser crystallization with an excimer laser again after thermal crystallization, which is also performed in this embodiment. Thereafter, the amorphous silicon becomes completely polycrystalline silicon. The islands 1102 and 1103 can be formed by patterning a photoresist by photolithography using polycrystal silicon and etching the polycrystal silicon. In the island 1102, a single transistor of P channel or N channel is formed later, and in the island 1103, a transistor such as a combination of P channel and N channel is formed.
[0232]
A substrate in which a base film 1101 and islands 1102 and 1103 are formed on an insulating substrate 1100 is set in a multi-chamber system including an ECR plasma processing apparatus in which the present invention can be implemented. Due to long exposure to the atmosphere and direct contact with the photoresist, there are carbon contaminants on the islands 1102 and 1103 containing carbon single and double bonds.
[0233]
First, active oxygen such as oxygen ions, oxygen radicals, and ozone is generated from oxygen using ECR plasma, thereby cleaning the insulating substrate 1100. Since only the base film 1101 and the islands 1102 and 1103 are formed on the insulating substrate 1100, there is no influence of the charge in the active oxygen. Therefore, a high frequency bias is applied to the insulating substrate 1100 to cause oxygen ions. Sputtering can be performed at the same time. However, since the surfaces of the islands 1101 and 1102 are regions for forming a channel, a high frequency bias is not applied to the substrate in order to prevent damage due to sputtering. Pressure is 1x10 ^-3 ~ 5x10 ^-Five Torr, but typically 5x10 ^-Four Perform in Torr. Microwave power is 500-2000W, typically 1200W. The substrate temperature is from room temperature to 500 ° C., typically 250 ° C. The flow rate of oxygen is 5 to 200 SCCM, typically 80 SCCM.
[0234]
After removing carbon contaminants containing mainly double bonds of carbon with active oxygen, carbon contaminants containing mainly single bonds of carbon are removed with active hydrogen using ECR plasma. No high frequency bias is applied and sputtering with hydrogen ions is not performed. Removal of carbon contaminants containing primarily single bonds of carbon. Pressure is 1x10 ^-3 ~ 5x10 ^-Five Torr, but typically 5x10 ^-Four Perform in Torr. Microwave power is 500-2000W, typically 1200W. The substrate temperature is from room temperature to 500 ° C., typically 250 ° C. The hydrogen flow rate is 5 to 200 SCCM, typically 80 SCCM.
[0235]
Cleaning of the islands 1102 and 1103 with active oxygen and active hydrogen first removes carbon contaminants containing carbon double bonds with active oxygen, followed by carbon containing single carbon bonds with active hydrogen. Although pollutants are removed, carbon contaminants containing carbon single bonds can be removed first with active hydrogen, and then carbon contaminants containing carbon double bonds can be removed with active oxygen. Good. At the same time, carbon contaminants containing carbon single and double bonds may be removed by active hydrogen and active oxygen.
[0236]
After removing carbon contaminants using ECR plasma, a gate insulating film 1104 is formed in a separate processing chamber of the multi-chamber system while keeping the surfaces of the islands 1102 and 1103 clean. FIG. 11A is completed. As the gate insulating film 1104, an oxide film such as dry thermal oxidation, wet thermal oxidation, CVD from silane and oxygen, CVD from silane and nitrous oxide, CVD from TEOS, oxygen or ozone, or a nitrogen-doped oxide film is used. . Alternatively, silicon nitride using silane, nitrogen, and ammonia is used. Alternatively, the oxide film and the nitride film are formed by multilayer lamination of two or more layers of the same type or different types.
[0237]
In this embodiment, nitrogen-doped silicon oxide is formed using parallel plate plasma CVD. The surfaces of the islands 1103 and 1104 are cleaned using ECR plasma, and the clean surfaces are not exposed to the atmosphere, and from the ECR plasma processing chamber through the connection chamber or directly from the ECR processing chamber without the connection chamber. Then, the substrate is transferred to the parallel plate type plasma CVD processing chamber.
[0238]
Therefore, in this embodiment, nitrogen-doped silicon oxide using silane and nitrous oxide is used as the gate insulating film 1104. Film formation conditions are silane: nitrous oxide = 1: 5 to 40, typically 1:20. The substrate temperature is 250 to 500 ° C., typically 380 ° C. The high frequency is 5 to 300 MHz, typically 60 MHz. High frequency power to be input is 0.05 to 2 W / cm ² Typically 0.5 W / cm ² . The film is formed at a pressure of 0.1 to 2 Torr, typically 0.5 Torr. The film thickness is 200 to 2000 mm and typically 1500 mm.
[0239]
After the gate insulating film 1104 is formed, the surface of the gate insulating film 1104 is cleaned with active oxygen and active hydrogen by performing ECR plasma treatment again. After the cleaning is completed, the substrate is transferred to the conductive film deposition chamber of the multi-chamber system. Here, in the case where the substrate can be transferred to the conductive film deposition chamber without being exposed to the atmosphere after the gate insulating film 1104 is formed, the gate insulating film 1104 is continuously formed without cleaning according to the present invention. The substrate may be transferred to the conductive film deposition chamber through the connection chamber.
[0240]
In the conductive film deposition chamber, an electrode material for the gate electrode 1105 is deposited. As the electrode material, a metal material such as aluminum, tantalum, titanium, or chromium, or a semiconductor material such as doped polysilicon doped with impurities at a high concentration is formed. Examples of the film forming method include DC sputtering, RF sputtering, resistance heating evaporation, electron beam evaporation, and low pressure CVD.
[0241]
In this embodiment, a sputtering film forming chamber in which aluminum is formed by DC magnetron sputtering is used. As a target material for sputtering, a material doped with silicon or scandium to improve aluminum hillock and heat resistance for heating in a later step is used. Typically, a target obtained by doping scandium with aluminum is used. The scandium doping amount is 0.05 to 1 wt%, and typically an aluminum target doped with 0.18 wt% is used.
[0242]
The film forming conditions are as follows: argon is flowed at 10-30 SCCM, typically 20 SCCM, pressure is 1-10 mTorr, typically 2 mTorr, input power is 500-3000 W, typically 1500 W, and the substrate temperature is Film is formed at room temperature. The film thickness is 2000 to 6000 mm, and typically 4000 mm is formed.
[0243]
After the conductive film for the gate electrode 1105 is formed, the conductive film is taken out into the atmosphere, the resist is patterned by photolithography, and aluminum is etched to form the gate electrode 1105. After the gate electrode 1105 is formed, boron and phosphorus are implanted through the gate insulating film 1104 by ion implantation using the gate electrode 1105 as a mask. At this time, the island 1102 side that becomes a single-channel transistor is masked with a photoresist or the like except for the required boron or phosphorus implantation, and the island 1103 having the P channel and the N channel as in the CMOS has a gate electrode. The area to be masked is different between the implantation of boron in two of 1105 and the implantation of phosphorus.
[0244]
After the boron and phosphorus implantation is completed, the region amorphized by the implantation is crystallized again by the laser beam 1106 to form a source / drain region 1107, which is shown in FIG.
[0245]
After that, an interlayer insulating film 1108 and a pixel electrode material are formed over the substrate, and a pixel electrode 1109 obtained by patterning the film is formed, so that FIG. Here, when the interlayer insulating film 1108 is formed, cleaning according to the present invention is performed. The substrate surface is cleaned with active oxygen and active hydrogen using ECR plasma. Since a gate-insulated transistor is formed on the substrate, it can be influenced by the charge in active oxygen. Therefore, a high frequency bias is applied and sputtering with oxygen ions is not performed. Removal of carbon contaminants mainly containing carbon double bonds. Pressure is 1x10 ^-3 ~ 5x10 ^-Five Torr, but typically 3x10 ^-Four Perform in Torr. Microwave power is 500-2000W, typically 1200W. The substrate temperature is from room temperature to 500 ° C., typically 250 ° C. The flow rate of oxygen is 5 to 200 SCCM, typically 80 SCCM.
[0246]
After removing carbon contaminants containing mainly double bonds of carbon with active oxygen, carbon contaminants containing mainly single bonds of carbon are removed with active hydrogen using ECR plasma. Since a gate-insulated transistor is formed on the substrate, it can be influenced by the charge in active oxygen. Therefore, a high frequency bias is applied and sputtering with oxygen ions is not performed. Removal of carbon contaminants containing primarily single bonds of carbon. Pressure is 1x10 ^-3 ~ 5x10 ^-Five Torr, but typically 5x10 ^-Four Perform in Torr. Microwave power is 500-2000W, typically 1200W. The substrate temperature is from room temperature to 500 ° C., typically 250 ° C. The hydrogen flow rate is 5 to 200 SCCM, typically 80 SCCM.
[0247]
Here, the cleaning with active hydrogen can also serve as a so-called hydrogenation in which the grain boundary of polycrystalline silicon is terminated with hydrogen. However, in order to enhance the hydrogenation effect, a higher effect can be obtained by forming a dense film such as a nitride film on the film. After cleaning is completed, the surface is cleaned so that the clean surface is not exposed to the atmosphere, and from the ECR plasma processing chamber through the connection chamber or directly from the ECR processing chamber without the connection chamber. The substrate is transferred to the processing chamber.
[0248]
Therefore, in this embodiment, silicon oxide using TEOS and oxygen is used as the interlayer insulating film 1108. Film forming conditions are TEOS: oxygen = 1: 2 to 15, typically 1: 5. The substrate temperature is 200 to 500 ° C., typically 300 ° C. The high frequency is 5 to 300 MHz, typically 13.56 MHz. High frequency power to be input is 0.05 to 2 W / cm ² Typically 0.7W / cm ² . The film is formed at a pressure of 0.1 to 2 Torr, typically 0.5 Torr. The film thickness is 5000 to 15000 mm, and typically 9000 mm is formed.
[0249]
Here, in order to enhance the effect of the cleaning also serving as hydrogenation, it is better to form a silicon nitride film of about 200 to 500 mm under the silicon oxide. In addition, after the cleaning is completed, instead of transferring the substrate to the parallel plate plasma CVD chamber, if an oxide film or a nitrogen-doped oxide film is formed as it is using ECR plasma CVD, a dense correlation insulating film 1108 is formed. The effect is further increased.
[0250]
In the case of film formation by ECR plasma CVD, in the case of an oxide film, oxygen is converted into plasma in the ECR region, and silane is introduced in the vicinity of the substrate, thereby forming silicon oxide. In the case of nitrogen doping, nitrous oxide or the like may be used instead of oxygen. The pixel electrode material on the correlation insulating film 1108 is transferred to the sputtering chamber without exposing the substrate to the atmosphere, and ITO is continuously formed by reactive sputtering. After film formation, patterning is performed by fatso and etching to form a pixel electrode 1109, which is shown in FIG.
[0251]
next, Interlayer Holes for contact of the source / drain 1107 are formed in the insulating film 1108 by photolithography and etching. , A conductive film for contact is formed thereon. Form a contact conductive film before First, active oxygen such as oxygen ions, oxygen radicals, and ozone is generated by oxygen using ECR plasma, thereby cleaning the surface of the interlayer insulating film 1108 and the contact hole. Since the transistor is formed, there is an influence due to the charge in the active oxygen, but in order to lower the contact resistance, a weak substrate bias is applied in order to simultaneously perform sputtering with some oxygen ions. Pressure is 1x10 ^-3 ~ 5x10 ^-Five Torr, but typically 5x10 ^-Four Perform in Torr. Microwave power is 500-2000W, typically 1200W. The substrate temperature is from room temperature to 500 ° C., typically 250 ° C. The flow rate of oxygen is 5 to 200 SCCM, typically 80 SCCM. The substrate bias is 0.05 to 0.5 W / cm at 2 to 60 MHz as high frequency power. ² Typically 0.1W / cm at 20MHz ² Apply.
[0252]
After removing carbon contaminants containing mainly double bonds of carbon with active oxygen, carbon contaminants containing mainly single bonds of carbon are removed with active hydrogen using ECR plasma. High frequency bias is applied to some extent and sputtering with hydrogen ions is performed. Removal of carbon contaminants containing primarily single bonds of carbon. Pressure is 1x10 ^-3 ~ 5x10 ^-Five Torr, but typically 5x10 ^-Four Perform in Torr. Microwave power is 500-2000W, typically 1200W. The substrate temperature is from room temperature to 500 ° C., typically 250 ° C. The hydrogen flow rate is 5 to 200 SCCM, typically 80 SCCM. The substrate bias is 0.05 to 0.5 W / cm as high frequency power. ² Typically 0.1 W / cm ² Apply.
[0253]
In order to maintain the clean surface with reduced carbon contamination by cleaning the contact holes, the substrate is moved to the sputtering process chamber without exposing the substrate to the atmosphere. Aluminum is deposited by sputtering as the contact conductive film. A contact electrode 1110 is formed by photolithography and etching, as shown in FIG.
[0254]
11E is formed by forming a protective film 1111. Before the protective film 1111 is formed, carbon contaminants by active oxygen and active hydrogen using ECR plasma according to the present invention are removed, and at the same time, A protective film 1111 is formed after performing the process of hydrogenation. As the protective film 1111, silicon nitride, a polyimide resin film, or the like is used.
[0255]
The completed thin film transistor for the active matrix panel has a pixel defect generation rate reduced by about 1/3 in the pressure cooker test as compared with a pressure cooker test, which was manufactured in the same process except that the present invention was not used. In addition, regarding the electrical characteristics, the threshold difference between adjacent TFTs was 0.018V using the present invention, whereas it was as large as 0.025V using the present invention.
[0256]
Example 9
FIG. 12 shows a TFT process using polycrystalline silicon for lateral growth using the present invention. The ECR plasma in the multi-chamber is used for the insulating substrate 1200 to remove carbon contaminants including a carbon single bond such as C-C and a carbon double bond such as C = C on the insulating substrate 1200. To do , First, active oxygen such as oxygen ions, oxygen radicals, and ozone is generated from oxygen using ECR plasma, thereby cleaning the insulating substrate 1200.
[0257]
Since no film is formed on the insulating substrate 1200, there is no influence of the charge in the active oxygen. Therefore, a high frequency bias is applied to the insulating substrate 1200 and sputtering with oxygen ions is performed simultaneously. Remove carbon contaminants containing double bonds. Pressure is 1x10 ^-3 ~ 5x10 ^-Five Torr, but typically 3x10 ^-Four Perform in Torr. Microwave power is 500-2000W, typically 1200W. The substrate temperature is from room temperature to 500 ° C., typically 250 ° C. The flow rate of oxygen is 5 to 200 SCCM, typically 80 SCCM. The substrate bias is 0.05 to 1.0 W / cm as high frequency power. ² Typically 0.3 W / cm ² Apply.
[0258]
After removing carbon contaminants containing mainly double bonds of carbon with active oxygen, carbon contaminants containing mainly single bonds of carbon are removed with active hydrogen using ECR plasma. Since no film is formed on the insulating substrate 1200, there is no influence of the charge in the active hydrogen. Therefore, a high frequency bias is applied to the insulating substrate 1200 and sputtering with hydrogen ions is performed simultaneously. Removal of carbon contaminants containing single bonds. Pressure is 1x10 ^-3 ~ 5x10 ^-Five Torr, but typically 5x10 ^-Four Perform in Torr. Microwave power is 500-2000W, typically 1200W. The substrate temperature is from room temperature to 500 ° C., typically 250 ° C. The hydrogen flow rate is 5 to 200 SCCM, typically 80 SCCM. The substrate bias is 0.05 to 1.0 W / cm as high frequency power. ² Typically 0.2W / cm ² Apply.
[0259]
After the carbon cleaning on the insulating substrate 1200 is completed, the base film 1201 is formed without being exposed to the air. As the base film 1201, silicon oxide, nitrogen-doped silicon oxide, phosphorus-doped silicon oxide, silicon nitride, or the like is formed. As a film forming method, low pressure CVD, sputtering, parallel plate plasma CVD, ECR plasma CVD, plasma CVD such as ICP plasma CVD, or the like is used. Typically, parallel plate type plasma CVD is used.
[0260]
The film forming conditions are typically 400 ° C. at a substrate temperature of 300 to 600 ° C. Regular tetraethyl silicate (so-called TEOS): oxygen = 1: 1 to 20, typically 1: 5. The pressure is 0.1 to 2 Torr, and typically 0.3 Torr. The high frequency applied to the parallel plate electrodes is 5 to 30 MHz, typically 13.56 MHz, and the power is 0.05 to 2.0 W / cm. ² Typically 0.7W / cm ² Apply. The thickness of the base film 1101 is 100 to 5000 mm, typically 2000 mm.
[0261]
When the formation of the base film 1201 is completed, amorphous silicon 1202 serving as an active layer is formed in another processing chamber of the multi-chamber system without being exposed to the atmosphere. As a method for forming the amorphous silicon 1202, low-pressure CVD, sputtering, plasma CVD such as parallel plate plasma CVD, ECR plasma CVD, or ICP plasma CVD is used. Typically, parallel plate type plasma CVD is used.
[0262]
In this embodiment, amorphous silicon 1202 is formed using a parallel plate type plasma CVD apparatus. Deposition conditions are typically 300 ° C. at a substrate temperature of 150-600 ° C. SiH as reaction gas _Four 10 to 500 SCCM, typically 55 SCCM is used. The pressure is 0.1 to 2 Torr, and typically 0.75 Torr. The high frequency applied to the parallel plate electrodes is 5 to 30 MHz, typically 13.56 MHz, and the power is 0.01 to 2.0 W / cm. ² Typically 0.05 W / cm ² Apply. The thickness of the amorphous silicon 1202 is 100 to 5000 mm, and typically 500 mm is formed. This results in FIG.
[0263]
After the amorphous silicon 1202 is formed, a thin oxide film 1203 is formed on the amorphous silicon 1202. This is because the oxide film 1203 having a thickness of 10 to 30 mm is formed by plasma oxidation or ozone oxidation using oxygen plasma before the substrate is put out into the atmosphere, or the oxide film having a thickness of 10 to 50 mm by wet oxidation using nitric acid taken out into the atmosphere. 1203 is formed. When performing plasma oxidation or ozone oxidation, since it is performed at a pressure as close to atmospheric pressure as possible, it is different from the removal of carbon contaminants by active oxygen according to the present invention.
[0264]
Thereafter, the photoresist 1204 is patterned by photolithography to form an opening 1205, and the opening 1205 portion of the oxide film 1203 is removed by wet etching or dry etching. Thereafter, using a method as disclosed in Japanese Patent Application Laid-Open No. 6-232059 by the present applicant, nickel 1206 is attached on the photoresist 1206 and in the opening 1205 on the amorphous silicon 1202 and becomes FIG. 12B. .
[0265]
Next, the photoresist 1204 is peeled off to obtain FIG. The attached nickel 1206 remains only on the opening 1205 opened in the oxide film 1203. This is grown in nitrogen at 400 to 600 ° C., typically at 500 ° C. for 1 hour, with the opening 1205 serving as a nucleus and grown laterally, and the amorphous silicon 1202 changes to polycrystalline silicon 1202.
[0266]
Thereafter, oxide film 1203 and polycrystalline silicon 1202 are patterned at the same time to complete island 1207. Since this island 1207 is made of polycrystalline silicon 1202 which has been laterally grown, the crystal grain size is as large as several μm. Next, a substrate is set in a multi-chamber system including an ECR plasma processing apparatus in which the present invention can be implemented. The island 1207 has carbon contaminants including single and double carbon bonds because it has been in the atmosphere for a long time and has been in direct contact with the photoresist.
[0267]
First, active oxygen such as oxygen ions, oxygen radicals, and ozone is generated from oxygen using ECR plasma, thereby cleaning the island 1207. Since only the base film 1201 and the island 1207 are formed on the insulating substrate 1200, there is no influence of the charge in the active oxygen. Therefore, a high frequency bias is applied to the insulating substrate 1200 and sputtering by oxygen ions is also performed. Although it can be performed simultaneously, since the surface of the island 1207 becomes a region for forming a channel, a high frequency bias is not applied to the substrate in order to prevent damage due to sputtering. Pressure is 1x10 ^-3 ~ 5x10 ^-Five Torr, but typically 5x10 ^-Four Perform in Torr. Microwave power is 500-2000W, typically 1200W. The substrate temperature is from room temperature to 500 ° C., typically 250 ° C. The flow rate of oxygen is 5 to 200 SCCM, typically 80 SCCM.
[0268]
After removing carbon contaminants containing mainly double bonds of carbon with active oxygen, carbon contaminants containing mainly single bonds of carbon are removed with active hydrogen using ECR plasma. No high frequency bias is applied and sputtering with hydrogen ions is not performed. Removal of carbon contaminants containing primarily single bonds of carbon. Pressure is 1x10 ^-3 ~ 5x10 ^-Five Torr, but typically 5x10 ^-Four Perform in Torr. Microwave power is 500-2000W, typically 1200W. The substrate temperature is from room temperature to 500 ° C., typically 250 ° C. The hydrogen flow rate is 5 to 200 SCCM, typically 80 SCCM.
[0269]
Cleaning the island 1207 with active oxygen and active hydrogen first removes carbon contaminants containing carbon double bonds with active oxygen, and then removes carbon contaminants containing carbon single bonds with active hydrogen. Although being removed, carbon contaminants containing carbon single bonds may be removed first with active hydrogen, followed by carbon contaminants containing carbon double bonds with active oxygen. At the same time, carbon contaminants containing carbon single and double bonds may be removed by active hydrogen and active oxygen.
[0270]
After removing carbon contaminants using ECR plasma, a gate insulating film 1208 is formed in another processing chamber of the multi-chamber system while the surface of the island 1207 is kept clean. As the gate insulating film 1208, an oxide film such as dry thermal oxidation, wet thermal oxidation, CVD from silane and oxygen, CVD from silane and nitrous oxide, CVD from TEOS, oxygen or ozone, or a nitrogen-doped oxide film is used. . Alternatively, silicon nitride using silane, nitrogen, and ammonia is used. Alternatively, the oxide film and the nitride film are formed by multilayer lamination of two or more layers of the same type or different types.
[0271]
In this embodiment, nitrogen-doped silicon oxide is formed using parallel plate plasma CVD. The surface of the island 1207 is cleaned using ECR plasma so that the clean surface is not exposed to the atmosphere, and directly from the ECR plasma processing chamber through the connection chamber or directly from the ECR processing chamber without the connection chamber. The substrate is transferred to the flat plate type plasma CVD processing chamber.
[0272]
Therefore, in this embodiment, nitrogen-doped silicon oxide using silane and nitrous oxide is used as the gate insulating film 1208. Film formation conditions are silane: nitrous oxide = 1: 5 to 40, typically 1:20. The substrate temperature is 250 to 500 ° C., typically 380 ° C. The high frequency is 5 to 300 MHz, typically 60 MHz. High frequency power to be input is 0.05 to 2 W / cm ² Typically 0.5 W / cm ² . The film is formed at a pressure of 0.1 to 2 Torr, typically 0.5 Torr. The film thickness is 200 to 2000 mm and typically 1500 mm.
[0273]
After the gate insulating film 1208 is formed, the surface of the gate insulating film 1208 is cleaned with active oxygen and active hydrogen by performing ECR plasma treatment again. After the cleaning is completed, the substrate is transferred to the conductive film deposition chamber of the multi-chamber system. Here, in the case where the substrate can be transferred to the conductive film deposition chamber without exposing the substrate to the atmosphere after the gate insulating film 1208 is formed, the gate insulating film 1208 is continuously formed without cleaning according to the present invention. The substrate may be transferred to the conductive film deposition chamber through the connection chamber.
[0274]
In the conductive film deposition chamber, an electrode material for the gate electrode 1209 is deposited. As the electrode material, a metal material such as aluminum, tantalum, titanium, or chromium, or a semiconductor material such as doped polysilicon doped with impurities at a high concentration is formed. Examples of the film forming method include DC sputtering, RF sputtering, resistance heating evaporation, electron beam evaporation, and low pressure CVD.
[0275]
In this embodiment, a sputtering film forming chamber in which aluminum is formed by DC magnetron sputtering is used. As a target material for sputtering, a material doped with silicon or scandium to improve aluminum hillock and heat resistance for heating in a later step is used. Typically, a target obtained by doping scandium with aluminum is used. The scandium doping amount is 0.05 to 1 wt%, and typically an aluminum target doped with 0.18 wt% is used.
[0276]
The film forming conditions are as follows: argon is flowed at 10-30 SCCM, typically 20 SCCM, pressure is 1-10 mTorr, typically 2 mTorr, input power is 500-3000 W, typically 1500 W, and the substrate temperature is Film is formed at room temperature. The film thickness is 2000 to 6000 mm, and typically 4000 mm is formed.
[0277]
After the conductive film for the gate electrode 1209 is formed, the conductive film is taken out into the atmosphere, the resist is patterned by photolithography, and aluminum is etched to form the gate electrode 1209. After the gate electrode 1209 is formed, boron or phosphorus is implanted through the gate insulating film 1208 and the oxide film 1203 using the gate electrode 1209 as a mask by ion implantation.
[0278]
After the boron or phosphorus implantation is completed, the region amorphized by the implantation is crystallized again by laser light to form source / drain regions 1210. Thereafter, an interlayer insulating film 1211 is formed over the substrate. Here, when the interlayer insulating film 1211 is formed, cleaning according to the present invention is performed. The substrate surface is cleaned with active oxygen and active hydrogen using ECR plasma. Since a gate-insulated transistor is formed on the substrate, it can be influenced by the charge in active oxygen. Therefore, a high frequency bias is applied and sputtering with oxygen ions is not performed. Removal of carbon contaminants mainly containing carbon double bonds. Pressure is 1x10 ^-3 ~ 5x10 ^-Five Torr, but typically 3x10 ^-Four Perform in Torr. Microwave power is 500-2000W, typically 1200W. The substrate temperature is from room temperature to 500 ° C., typically 250 ° C. The flow rate of oxygen is 5 to 200 SCCM, typically 80 SCCM.
[0279]
After removing carbon contaminants containing mainly double bonds of carbon with active oxygen, carbon contaminants containing mainly single bonds of carbon are removed with active hydrogen using ECR plasma. Since a gate-insulated transistor is formed on the substrate, it can be influenced by the charge in active oxygen. Therefore, a high frequency bias is applied and sputtering with oxygen ions is not performed. Removal of carbon contaminants containing primarily single bonds of carbon. Pressure is 1x10 ^-3 ~ 5x10 ^-Five Torr, but typically 5x10 ^-Four Perform in Torr. Microwave power is 500-2000W, typically 1200W. The substrate temperature is from room temperature to 500 ° C., typically 250 ° C. The hydrogen flow rate is 5 to 200 SCCM, typically 80 SCCM.
[0280]
Here, the cleaning with active hydrogen can also serve as a so-called hydrogenation in which the grain boundary of polycrystalline silicon is terminated with hydrogen. However, in order to enhance the hydrogenation effect, a higher effect can be obtained by forming a dense film such as a nitride film on the film. After cleaning is completed, the surface is cleaned so that the clean surface is not exposed to the atmosphere, and from the ECR plasma processing chamber through the connection chamber or directly from the ECR processing chamber without the connection chamber. The substrate is transferred to the processing chamber.
[0281]
Therefore, in this embodiment, silicon oxide using TEOS and oxygen is used as the interlayer insulating film 1211. Film forming conditions are TEOS: oxygen = 1: 2 to 15, typically 1: 5. The substrate temperature is 200 to 500 ° C., typically 300 ° C. The high frequency is 5 to 300 MHz, typically 13.56 MHz. High frequency power to be input is 0.05 to 2 W / cm ² Typically 0.7W / cm ² . The film is formed at a pressure of 0.1 to 2 Torr, typically 0.5 Torr. The film thickness is 5000 to 15000 mm, and typically 9000 mm is formed.
[0282]
Here, in order to enhance the effect of the cleaning also serving as hydrogenation, it is better to form a silicon nitride film of about 200 to 500 A under the silicon oxide. In addition, when the substrate is not transferred to the parallel plate plasma CVD chamber after the cleaning is completed, an oxide film or a nitrogen-doped oxide film is formed using ECR plasma CVD as it is. Interlayer An insulating film 1211 is formed and hydrogen Conversion The effect of further increases.
[0283]
In the case of film formation by ECR plasma CVD, in the case of an oxide film, oxygen is converted into plasma in the ECR region, and silane is introduced in the vicinity of the substrate, thereby forming silicon oxide. In the case of nitrogen doping, nitrous oxide or the like may be used instead of oxygen. Next, holes for contact of the source / drain 1210 are formed in the interlayer insulating film 1211 by photolithography and etching. A conductive film for contact is formed thereon. Prior to the formation of the contact conductive film, first, oxygen is generated in the ECR plasma to generate active oxygen such as oxygen ions, oxygen radicals, and ozone, whereby the surface of the interlayer insulating film 1211 and the contact hole is formed. Perform cleaning. Since the transistor is formed, there is an influence due to the charge in the active oxygen, but in order to lower the contact resistance, a weak substrate bias is applied in order to simultaneously perform sputtering with some oxygen ions. Pressure is 1x10 ^-3 ~ 5x10 ^-Five Torr, but typically 5x10 ^-Four Perform in Torr. Microwave power is 500-2000W, typically 1200W. The substrate temperature is from room temperature to 500 ° C., typically 250 ° C. The flow rate of oxygen is 5 to 200 SCCM, typically 80 SCCM. The substrate bias is 0.05 to 0.5 W / cm at 2 to 60 MHz as high frequency power. ² Typically 0.1W / cm at 20MHz ² Apply.
[0284]
After removing carbon contaminants containing mainly double bonds of carbon with active oxygen, carbon contaminants containing mainly single bonds of carbon are removed with active hydrogen using ECR plasma. High frequency bias is applied to some extent and sputtering with hydrogen ions is performed. Removal of carbon contaminants containing primarily single bonds of carbon. Pressure is 1x10 ^-3 ~ 5x10 ^-Five Torr, but typically 5x10 ^-Four Perform in Torr. Microwave power is 500-2000W, typically 1200W. The substrate temperature is from room temperature to 500 ° C., typically 250 ° C. The hydrogen flow rate is 5 to 200 SCCM, typically 80 SCCM. The substrate bias is 0.05 to 0.5 W / cm as high frequency power. ² Typically 0.1 W / cm ² Apply.
[0285]
In order to maintain the clean surface with reduced carbon contamination by cleaning the contact holes, the substrate is moved to the sputtering process chamber without exposing the substrate to the atmosphere. Aluminum is deposited by sputtering as the contact conductive film. Film formation rear A contact electrode 1212 is formed by photolithography and etching, resulting in FIG.
[0286]
Thus, the present invention is used to form a thin film transistor having a large crystal grain size, that is, high mobility, using polycrystalline silicon grown laterally. Comparing TFTs that were made the same in all other processes without using the present invention and TFTs in the process that included the present invention, the TFT with a threshold value of 2 V with N channel is not used. In the P channel, it was -3V, but in the case of using the present invention, the N channel was 1V and the P channel was -1.5V. Also, the mobility is 90 cm in the N channel without using the present invention. ² / Vsec, 80cm with P channel ² / Vsec, but the one using the present invention is 120 cm with an N channel. ² / 100sec with P channel at Vsec ² / Vsec.
[0287]
【The invention's effect】
As described above, the present invention relates to carbon contaminant removal in a semiconductor device manufacturing method, and the semiconductor interface is particularly important by removing contamination of the substrate surface due to all carbon contamination including carbon single bonds. This has a great effect on improving the characteristics and reliability of semiconductors such as MOS and MIS structures.
[Brief description of the drawings]
FIG. 1 is a graph showing the degree of carbon impurity removal by XPS on a substrate surface according to the present invention.
FIG. 2 is a graph showing a degree of removal of carbon impurities by XPS on a substrate surface according to a conventional technique.
FIG. 3 is a diagram showing an apparatus for carrying out the present invention.
FIG. 4 is a view showing an apparatus for carrying out the present invention.
FIG. 5 is a diagram showing a part of the principle of the present invention.
FIG. 6 shows an apparatus for carrying out the present invention.
FIG. 7 shows an apparatus for carrying out the present invention.
FIG. 8 is a diagram showing an apparatus for carrying out the present invention.
FIG. 9 is a view showing an apparatus for carrying out the present invention.
FIG. 10 is a diagram showing an apparatus for carrying out the present invention.
FIG. 11 shows a semiconductor process using the present invention.
FIG. 12 is a diagram showing a semiconductor process using the present invention.
[Explanation of symbols]
1100 Insulating substrate
1101 Underlayer
1102 Island
1103 Island
1104 Gate insulating film
1105 Gate electrode
1106 laser
1107 Source / drain
1108 Interlayer film
1109 Pixel electrode
1110 Contact electrode
1111 Protective film

Claims (10)

In the first chamber, after hydrogen having been activated by a microwave and a magnetic field under reduced pressure is used to reduce impurities including a single bond of carbon on at least a part of the surface of the insulating substrate,
A method of manufacturing a semiconductor device, comprising: forming a base film on the insulating substrate in the second chamber. In the first chamber, after reducing impurities including a single bond and a double bond of at least a part of carbon on the surface of the insulating substrate using hydrogen and oxygen activated by a microwave and a magnetic field in a reduced pressure state,
A method of manufacturing a semiconductor device, comprising: forming a base film on the insulating substrate in the second chamber. In the first chamber, hydrogen and oxygen activated by a microwave and a magnetic field in a reduced pressure state are used to include at least a part of carbon single and double bonds formed on the insulating substrate. After reducing impurities,
A method of manufacturing a semiconductor device, wherein a film is formed on the surface in the second chamber. In claim 3,
A method of manufacturing a semiconductor device, wherein hydrogenation of a thin film transistor is performed simultaneously with reduction of carbon single bonds. In claim 3 or claim 4 ,
The semiconductor device manufacturing method, wherein the film is a gate insulating film, a gate electrode, an interlayer insulating film, a conductive film, or a protective film. In claim 3 or claim 4 ,
The method of manufacturing a semiconductor device, wherein the film is a silicon oxide film containing nitrogen. In any one of Claims 1 thru | or 6 ,
The method for manufacturing a semiconductor device, wherein the first chamber and the second chamber are the same chamber. In any one of Claims 1 thru | or 6 ,
The first chamber and the second chamber are different chambers, and the second chamber is separated from the first chamber by a gate valve during the formation of the base film or the film. Semiconductor device manufacturing method. In any one of Claims 1 thru | or 8 ,
There is a third chamber between the first chamber and the second chamber, and the insulating substrate is moved from the first chamber to the second chamber through the third chamber. A semiconductor device manufacturing method. In any one of Claims 1 thru | or 9 ,
The method for manufacturing a semiconductor device, wherein the hydrogen or the oxygen is activated using electron cyclotron resonance by a microwave and a magnetic field.

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