KR20030090650A - Method for producing parts and a vacuum processing system - Google Patents

Abstract

To produce a coated part that requires the same requirements for the coating as in the case of coating an epitaxial layer, a reactive gas is introduced into the process chamber PR to activate the reactive gas by low energy plasma discharge. In order to enhance the industrial utility of such a process, the process chamber PR is isolated (14) from the inner wall of the surrounding container 1 in such a method.

Description

METHOD FOR PRODUCING PARTS AND A VACUUM PROCESSING SYSTEM

A system therefor as well as a method of the type mentioned at the outset from Applicant's WO98 / 58099 (attached) are known. The document describes the reactive gas or reactive gas mixture introduced into the process chamber as the ion energy E at the part surface.

0 eV <E ≤ 15 eV

It is only described and claimed in detail to coat the workpiece with a quality sufficient for epitaxy as one or more plasma accelerated treatment steps activated by a low energy plasma discharge that results in The plasma generated by the low energy plasma discharge consists essentially of electrons, single and multiple charged ions, neutral particles (atoms, dissociated molecules), and neutral particles that are excited but not ionized. In the plasma disclosed in that document, the energy band of a single ionized ion

0 eV <E ≤ 15 eV

It is characteristic. 15 eV is the so-called sputtering limit that can cause damage to the substrate from its value when ions act on the substrate. The electrons themselves only contribute to heating the substrate up to 100 eV. In addition, in the highly preferred DC low pressure plasma generating apparatus of the present invention as will now be described, the above-described energy band of a single charged ion simultaneously limits the energy band of neutral particles and excited neutral particles present in the plasma to the upper limit. Known. The reason is that the neutral particles get a major share of their energy by collision with ions.

WO 98/58099 also describes in detail the vacuum treatment system for the coatings described above, which includes a vacuum chamber containing a workpiece support, a plasma generating device for generating plasma in the vacuum chamber, and a gas tank device containing one or more reactive gases. It is provided with the gas inflow apparatus which is connected with and puts gas into a vacuum chamber. The plasma generator is specified and described as a low pressure plasma generator (the cathode chamber is located with the process chamber via the shutter). The thermal cathode is assembled in the cathode chamber, and the anode device is assembled in the process chamber. Workpieces which are oriented downward in space are arranged with electrical insulation.

The principle of such a low pressure plasma generating device is also much more desirable for the method described herein compared to other known plasma generating methods (e.g. microwave plasma), since it can meet the above-mentioned energy properties significantly better. Because there is.

Thus, the present invention starts on the one hand with such a type of method and system and on the other hand, although further criteria must be met according to the purpose of the present invention as will now be described, in particular in WO98 / 58099. The disclosed method is also to be implemented by the present application.

WO98 / 58099 is hereby attached as a method specification.

In accordance with the preamble of claim 1, the present invention relates to a reactive gas or a mixture of

0 eV <E ≤ 15 eV

A method of manufacturing a component as an electronic device, an optoelectronic device, an optical device, or a precision mechanical device, or an intermediate material thereof, using one or more plasma accelerated processing steps activated by a low energy plasma discharge to cause

The invention furthermore provides a method for producing a virtual substrate, preferably a silicon / germanium based virtual substrate or a component thereof, as in accordance with the preamble of claim 28, wherein the method comprises at least one cleaning step. It is about. The present invention further relates to a vacuum processing system according to the preamble of claim 29 or 30.

Basically, the present invention relates to a method for manufacturing a part in which the same requirements are required as in the case of coating an epitaxial layer on the part.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings. Among the accompanying drawings,

1 shows schematically a first embodiment of a process module according to the invention for carrying out the method according to the invention;

FIG. 2 is a view similar to that of FIG. 1 showing a preferred embodiment of the process module according to FIG. 1 for carrying out the method according to the invention; FIG.

FIG. 3 is a view similar to that of FIG. 1 or FIG. 2, showing another process module type according to the invention for carrying out the process according to the invention, ie the cleaning according to the invention; FIG.

FIG. 4 is a view similar to the one of FIGS. 1 to 3 showing a variant embodiment of the process module shown in FIG. 3 for carrying out the process according to the invention, ie the cleaning according to the invention;

5 is a simplified illustration of a preferred embodiment of the process module according to the invention of FIG. 2, which may be modified to the process module of FIG. 3 or 4, carrying out the method according to the invention;

FIG. 6 shows that the magnetic field component parallel to the axis “A” with respect to the outlet axis “A” of the process module according to FIG. 5 is controlled and position modulated over a plane perpendicular to the outlet axis “A”. A graph showing that;

FIG. 7 is a view along the time axis that the workpiece is loaded continuously into the process module according to FIGS. 1 to 5, and after performing a predetermined number of processing steps or to self-clean the process module as needed;

8 shows the combination of the process module according to FIGS. 1 to 5 into an inline continuous installation;

9 is a simplified plan view of a combination of a process module according to FIGS. 1 to 5 into a circular plant or a cluster plant, in particular for producing a virtual substrate or a component based on the virtual substrate according to the invention.

In other words, it is an object of the present invention to provide a method or system of the type described above in which its industrial utility is significantly increased, particularly in terms of economic criteria of long durability life and high unit time throughput.

Therefore, the high system consistency that is desired to be obtained for the method of the type described above for the long service life required is to be ensured. In addition, the possibility of integrating the system on the one hand and on the other hand in an automated manufacturing process should be optimally implemented.

Such an object is achieved by isolating the process atmosphere from the inner wall of the surrounding vacuum vessel during the plasma promoting treatment step in the method of the type mentioned at the outset. In such a method, the basic recognition is to achieve the above-mentioned object by functionally isolating a structure which secures the necessary vacuum technical pressure relationship to the ambient pressure on the one hand and, on the other hand, the structure directly exposed to the treatment process.

According to WO98 / 58099, the inner surface of a vacuum chamber, usually made of stainless steel or Inox, is in direct contact with the process atmosphere. During the plasma promoting treatment step the vacuum chamber wall is heated, in particular where the workpiece or part is coated by a low energy plasma discharge, thus heating the inner surface. Therefore, when applied to industrial manufacturing, the treatment step process atmosphere is unacceptably contaminated or unacceptably residual gas partial pressure during the above-described process exposure, for example, based on various influences such as internal absorption behavior. This results in the formation. Here, the residual gas in the process atmosphere refers to a gas part which is neither derived from a plasma discharge working gas such as, for example, argon, nor derived from the introduced reactive gas or reactive gas mixture and its gas phase reaction product. By the measures according to the invention, it is now possible to minimize the effect on the process by the wall of the vacuum chamber.

The method according to the invention etches the surface of the part, such as (a) coating the part, (b) changing the material composition up to a predetermined penetration depth, or (c) in particular for patterning etching of the part in accordance with the spirit of claim 2. Very preferably used. In all of those mentioned, maintaining process conditions such as those necessary for the growth of the epitaxial layer is essential for the scope of the manufacturing process to be obtained according to the invention. Here, changing the material composition according to (b) according to the invention means injecting the material into a given target material in advance.

Further, the cleaning step according to claim 3 is provided as a plasma acceleration treatment step performed according to the present invention, or the cleaning step according to claim 4 is provided in addition to the plasma promotion step according to the present invention.

In a preferred configuration of the method according to the invention a virtual substrate is produced in accordance with the spirit of claim 5. A virtual substrate refers to a semiconductor wafer that has a specific layer structure, unlike a wafer made of a consistent single crystal semiconductor material, but which is also functionally used as a starting material for a semiconductor device.

Semiconductor material "A", for example, single crystal silicon in the form of a wafer serves as a starting substrate. On the starting substrate it is desirable to deposit a buffer layer, preferably consisting of a continuously varying fraction of semiconductor "A" and an additional semiconductor "B", typically a high fraction "A" and a low fraction "B". From the higher fraction "B" and lower fraction "A". It is referred to as a "gradient buffer layer." The structure of such a buffer layer is full defect. On the buffer layer grow a cover layer whose composition approximately matches that of the top buffer layer zone. The purpose of doing so is to obtain a defect-free mixed crystal layer without dislocations. Three components of such a base or substrate, a buffer layer, and a cover layer form a virtual substrate.

As is well known to those skilled in the art, it is also possible to deposit additional intermediate layers. A unique useful layer of the composition required for the desired properties of the semiconductor material is attached onto the virtual substrate. As a useful layer material, a mixture of two semiconductors can also be used, but a layer of pure semiconductor such as “B” can also be used. Typically, such a layer is thinned so that dislocations do not occur in the layer and the stress in the layer is kept intact (band gap engineering). Growth of such a useful layer can be combined with the formation of a virtual substrate, but a useful layer can be provided later on the prefabricated virtual substrate. According to the spirit of the present invention and claim 5, unlike the conventional method of using wet cleaning within the manufacturing range of the virtual substrate, the base or the above-described substrate is first treated by plasma accelerated cleaning. Thereafter, a hetero-epitaxial buffer layer is deposited and, if necessary, the cover layer described above. Subsequently, the useful layer to be used is optionally deposited according to the invention, or after the buffer layer has been deposited, the self-finished virtual substrate is subsequently provided via the cover layer to the useful layer deposition to be done later.

As already mentioned herein, known virtual substrate manufacturing methods (molecular beam epitaxy (MBE), ultra high vacuum CVD (UHVCVD), atomic layer deposition (ALD) And the wet chemical cleaning step used therein within the scope of the above) is regarded as an advance by itself, and it is considered to be an advance on its own, bringing the advantages of a very significant manufacturing technique.

As regards it is mentioned in the production method according to claim 28.

During the required industrial manufacturing process, it is often necessary to first clean the surface contaminants caused by, for example, the ambient atmosphere, for the parts to be treated later by the plasma-promoting treatment steps (a), (b) and (c) described above. to be.

In addition, after each of the plasma processing steps (a), (b), and (c) described above, a cleaning step may be necessary, for example, to clean the pollutant material or pollutant gas released during etching.

In that case, in the embodiment of the cleaning method, a reactive gas (hydrogen, hydrogen / inert gas mixture) that may degrade the material used for the casing in the process atmosphere may be used.

For this reason, according to claim 4, a metal casing having a relatively inexpensive process atmosphere is provided for such a cleaning step, or the cleaning process atmosphere is directly bordered on the inner wall of the surrounding vacuum vessel.

That is, for the treatment steps (a), (b), and (c) described above, it is much more likely to border the process atmosphere with a non-metal material, i.e., a material that is inert to the plasma activated reactive gas used, as just described below. desirable. However, it must also be ensured that such a treatment can reach the next treatment without degrading the cleaned surface of the part even in that cleaning step as if it is the deposition of an epitaxial layer. For this reason, the above-described low energy plasma is also used so that the ion energy at the surface of the part is specified even in the plasma cleaning step of the part.

Further, according to the spirit of claim 6, the components which are sequentially entered in the target process chamber, that is, in the sequential time order, are treated with one or more of the above-described plasma promoting processing steps, and the parts are processed after performing a predetermined number of such processing steps. An additional plasma acceleration treatment step, i.e., a process chamber cleaning step, is performed in the above-described target process chamber using no introduction or using a dummy. Such a process cleaning step is preferably carried out in two or more partial steps: firstly etching and then cleaning the etching residue, the latter being carried out in a plasma containing hydrogen, an inert gas, or mixtures thereof. desirable.

In view of the objectives set forth in accordance with the invention, in particular in terms of achieving a long service life, the process chamber is subjected to plasma accelerated cleaning several times after a given number of treatment steps. In that case, it is customary to process or clean the component in the process chamber in accordance with the processing step (a), (b) or (c), whether in accordance with the intent of claim 3 or in some cases in accordance with claim 4. . However, there may of course be a case where coating, etching or material composition change are sequentially performed in an order that can be programmed in a single target process chamber, or the parts are subsequently cleaned according to claim 3.

The measure according to the invention which isolates the process atmosphere from the vacuum vessel wall makes it possible to plasma chemically clean the process chamber or parts using a reactive gas which should not be exposed to the vacuum chamber wall. Due to the fact that the process chamber can be plasma-promoted self-cleaning after a number of parts processing steps given or given in advance, it can then be immediately available for part processing again, resulting in a durable service life for continuous operation. It will rise significantly. It is comparable, for example, for cleaning process chambers in accordance with WO98 / 58099.

Thus, to summarize the description so far, the coating of the part, the material composition change, the patterning etching of the part, or the part, while avoiding the wet chemical cleaning step in terms of the quality requirements required for epitaxy by the manufacturing method according to the invention Cleaning of the process chamber, and the midnight of the process chamber can be achieved simply by changing the process parameters, in particular the incoming reactive gas, between such treatment steps. By changing or omitting the isolation of the process atmosphere and the vacuum vessel, the same method can be carried out to clean the part during the manufacturing process of the part according to the present invention.

According to the aspect of claim 7, it is preferable that the parts are separately processed on the site by the two or more plasma acceleration treatment steps described above, and the transfer therebetween is performed in a vacuum. According to the intent of claim 8 it is a linear movement from the processing stage to the processing stage in terms of a linear installation, or along a circular path in terms of a circular installation known as the expression "cluster installation". In such cluster installations, by means of circular transfer, parts or workpieces are programmed in a processing station arranged around the circular transfer path and arranged so that they can be freely programmed as necessary.

In a very preferred embodiment of the method according to the invention (claim 9), the isolation between the process atmosphere and the surface of the vacuum vessel wall is inert to the plasma activated reactive gas or gas mixture in the state of fresh, preferably the dielectric surface or graphite. It is performed by bordering a process chamber on the surface.

During operation, ie specifically during coating (a), material composition change (b), or etching (c), in particular during patterning etching or during cleaning, any material is allowed to precipitate on the surface. However, such materials do not contaminate the process or only contaminate to an acceptable level. In such cases where the same processing steps are carried out on successive incoming parts in the same target process chamber, the reaction product material described above is coated on an isolation surface, preferably a dielectric or graphite isolation surface, which is inert in the state of new as described above. However, it is highly desirable to coat only to the extent that the resulting coating is reliably attached to the surface described above.

Providing the necessary inert surface, preferably the dielectric surface, is in terms of coating such material, whether by indirectly assembling the self-supporting wall portion facing inward on the inner wall of the vacuum vessel, Preferably the structure forming the dielectric surface may be adapted to attach directly on the inner surface of the vacuum vessel.

In a very preferred embodiment, however, it is preferred according to claim 10 to space the inert surface with intervening space at least along most of the face sections of the inner wall of the vacuum vessel. Such measures offer particular advantages in that the replacement of the isolation wall structure is possible, the convenience of inspection and repair, and the preset surface temperature as intended.

According to the aspect of claim 11, the process chamber and the above-described intervening space can be pumped the same or differently. This makes it possible, among other things, to create an atmosphere in the intervening space which imparts the desired thermal conductivity between the vacuum vessel wall and the surface described above, if necessary. In that case, if a high thermal conductivity gas such as helium is introduced into the intervening space and / or a higher pressure is at least temporarily realized in such intervening space than in the process chamber, then the heat conduction in that individual space is Higher than that of so that it may be possible to maintain the surface at the desired temperature. Here, it is to be pointed out that the thermal conduction below a certain vacuum pressure is reduced with pressure and depends on the thermal conductivity of the gas in question.

Preferred materials for the surface in the fresh state are specified in claim 12. In that regard, it is emphasized that when referring to a surface consisting of an inert material, preferably a dielectric material, it refers exclusively solely to the surface material of the surface facing the process chamber. In that case, such a surface is preferably formed by the surface of the isolation wall. In addition, the isolation walls may be coated. That is, for example, it may be formed of metal toward the vacuum vessel with an inert surface facing the process chamber or process atmosphere. In other words, from that point of view, the surface can be formed by a layer structure which enables the use of diamond-like material or diamond according to the spirit of claim 12.

It is known in the plasma chemistry method that the coating speed also increases as the temperature (and the plasma intensity supplied) increases. As described above, it may be highly desirable to coat the surface facing the process chamber with the reaction product of the plasma activated reaction gas corresponding to each process. In that case, however, great care must be taken to avoid any delamination of such coatings. Such recognition may be changed to the purpose that the coating speed of the aforementioned surface can be minimized by controlling the temperature of the aforementioned surface during the plasma promoting treatment step. Thereby, for example, it is possible to choose a coating rate of such impurities significantly lower than the rate of action on the part so that the process chamber is only self-cleaning after a relatively large number of parts have been processed. In that case, the coating is removed before the thickness of the coating reaches a threshold, for example in connection with peeling.

Here, the rate of action in the part means the coating rate, penetration rate, etching rate, cleaning rate, depending on the treatment.

In view of the object of the present invention, attention should also be paid to the degree of automation of the method or system. In view of this, in accordance with the purport of claim 13, a supply opening for a component is provided in the above-described surface, and the supply opening is inserted into the component and / or the component support such that the loading support is prevented from exiting the process chamber for processing of the component. Measure to close by.

In a further preferred embodiment a low energy plasma discharge according to claim 14 is implemented using an electron source having an electron energy of ≤ 100 eV, preferably of ≤ 50 eV, particularly preferably by DC discharge, in particular of the claims According to 15 it is preferred to implement by means of a thermoionic cathode, preferably by a direct heated thermionic cathode. In addition, it is even more desirable to directly expose the surface of the component being treated to plasma.

According to claim 16, it is also desirable to provide two or more anodes that have fallen on site in the process chamber for plasma discharge. It is preferred that such anodes can be heated separately, respectively. By controlling the potential applied to the anode and / or its temperature, the plasma density distribution in the process chamber can be set and controlled dynamically and / or statically. By static setting is meant a setting that is set once and left static for at least the processing step. Dynamic setting means processing in the form of any linear or nonlinear ramp function, whether in terms of sweeping during the processing step, or periodically or oscillating aperiodically in correspondence with a given curve shape. It means changing one or more of the above-described parameters at that time during the step. In particular, the measures mentioned in the latter make it possible to suppress the compensation or to change the plasma densities at the surface of the part as desired, taking into account the fluctuations in the process chamber during the treatment step.

Further, according to the intent of claim 17, a magnetic field is generated in the process chamber that statically or dynamically sets or controls the plasma density distribution at the part surface in the context of the just mentioned parameters, anode potential and / or anode temperature. It is desirable to. By changing such magnetic field to be controlled over time, it is possible to change the plasma density distribution along the part surface, especially as if the part is periodically moved into a statically distributed plasma. By sweeping the magnetic field in such a way that the plasma distribution along the surface of the statically maintained component is vibrated, it is as if the component is vibrating or rotationally moving, but not particularly advantageously in vacuum technology. You get

The reactive gas is dispensed according to claim 18 and introduced into the process atmosphere, in which case the component is preferably introduced in an inflow direction approximately parallel to the surface of the component and more preferably as an evenly spaced injection point from the surface of the component. Optimally expose the surface of to the plasma activated reactive gas and optimize the incoming reactive gas in terms of the reverse efficiency, ie, the share of the bioreactive gas introduced per unit time divided by the reactive gas still in the live gas phase pumped out per unit time. Will be utilized.

Residues as defined above, in order to have the effect of the above-mentioned processing steps, in particular steps (a), (b), (c), or cleaning of the part according to claim 3, with the quality required for the deposition of the epitaxial layer. The gas partial pressure is maintained at 10 ⁻⁸ mbar or less, preferably 10 ⁻⁹ mbar or less according to claim 10.

The at least one plasma promoting treatment step described above in the method according to the invention is to deposit a homo epitaxial layer or a hetero epitaxial layer in a first preferred embodiment. It is more preferred to deposit such a layer according to claim 21 as a silicon / germanium layer.

Furthermore, according to claim 22, a substantially disc-shaped part is produced as a part.

According to the aspect of claim 23, in another preferred embodiment, the component to be treated is a wafer made of a compound semiconductor, preferably of silicon wafer or gallium arsenide, indium phosphide, silicon carbide, or glass. Claim 24 specifies a layer material which is preferably deposited in the production process according to the invention.

In a very important embodiment of the manufacturing method according to the invention, a virtual substrate of the above-described type is preferred which contains silicon / germanium according to claim 25.

In a further embodiment of the manufacturing method according to the invention, according to claim 26 a part having a diameter of at least 150 mm, preferably at least 200 mm, more preferably at least 300 mm, in particular a part which is generally planar or disc shaped is produced.

In another preferred embodiment of the production method according to the invention the part is coated according to claim 27 at a coating rate of 60 nm / Min.

With regard to virtual substrates, especially silicon / germanium based virtual substrates, whether to clean the surface of the finished virtual substrate for subsequent processing steps or to clean an already epitaxially coated substrate for further provision of the virtual substrate. Whether to clean the base for epitaxial growth prior to the growth of the buffer layer, it is current practice to use a wet chemical cleaning method. Now, in the scope of the present invention, it has been confirmed that by using the above-described low energy plasma in the plasma accelerated cleaning step, the cleaning is implemented so that subsequent production of the virtual substrate or production of the parts starting from the virtual substrate is possible without any problems. Thereby, namely, by changing the wet chemical cleaning method to the plasma accelerated cleaning method, on the one hand, an excellent advantage is provided on the one hand, and by such confirmation, such plasma cleaning is applied to the manufacturing method of the virtual substrate or the manufacturing method of the component based thereon. It can be integrated. Thereby, a virtual substrate, preferably a silicon / germanium-based virtual substrate, comprising at least one cleaning step facilitated by a plasma in accordance with the teachings of claim 28 and exposing the workpiece to a reactive gas or gas mixture introduced into the process chamber. A method for manufacturing a component or a method for manufacturing a component based on a virtual substrate is provided. Such reactive gases or gas mixtures are activated by low energy plasma discharges such that ionic energy at the surface of the part is 15 eV or less.

With respect to highly complex surfaces, the surprising achievements of the present inventors by such dry cleaning methods result from the use of low energy plasmas as defined.

Claims 29 and 30 specify, in particular, a vacuum treatment system according to the invention, which is suitable for carrying out the method according to the above-mentioned features: According to claim 29, a plasma activated reactive gas or gas mixture with the process chamber inner wall surface fresh The material consists of a material which is inert to the material, preferably a dielectric material, and according to the spirit of claim 30, the process chamber comprising the process chamber is formed inwardly spaced apart from the wall of the vacuum chamber. Subsequently, preferred embodiments of the vacuum processing system according to the invention are specified in claims 42-60.

1 schematically shows a process module type I according to the invention. The chamber wall 1 of the vacuum vessel 3 surrounds the process chamber PR in which plasma is generated. The substrate support 5 is provided in the process chamber PR, and the supply line 7 communicates with the process chamber PR to one side, and the reactive gas tank installation 9 to the other. The process chamber PR is not more than 10 ^-8 mbar, preferably 10 ^-9 mbar, required for carrying out the production process according to the invention via a pumping connection line 11 as schematically shown as a vacuum pump 13. It is vacuum pumped to the following pressures. The structure of such a container meets UHV conditions (eg a closed metal vacuum vessel that can be heated). Almost all of the surface area of the chamber wall 1 surface facing the process chamber PR, typically made of stainless steel or Inox, is made of a material that is inert to the plasma activated reactive gas in the tank 9. . According to the embodiment of the process module type I shown in FIG. 1, the chamber wall 1 is hereby coated with the above-mentioned inert material, or at least the inner part of the wall portion of the above-mentioned inert material consists of the chamber wall 1 The coating or such inert material surface is indicated by reference numeral 15 in FIG. 1. The vacuum pumping of the process chamber PR to the required residual gas partial pressure described above generates the low energy plasma required according to the invention under the introduction of a working gas such as, for example, argon in the process chamber PR, such a low energy plasma. Consequently in the area of the substrate support 5 or

0 eV <E ≤ 15 eV

Generates the ion energy E. As the material of the surface 15 facing the process chamber PR, at least one of the materials exemplified in the dielectric material, and preferably in the following group G is used:

Quartz, graphite, silicon carbide, silicon nitride, aluminum oxide, titanium oxide, tantalum oxide, niobium oxide, zirconium oxide, diamond-like carbon or diamond, the last surface material is used as the layer material.

In figure 2 a preferred embodiment of process module type 1 according to the invention of figure 1 is also schematically shown in a view similar to the figure of figure 1. In FIG. 2, the same reference numerals are used for the parts already described in FIG. 1. Unlike the embodiment according to FIG. 1, in the embodiment according to FIG. 2 the process chamber PR is connected to the process chamber wall 14 spaced along most of the sections of the chamber wall 1, also made of stainless steel or inox. Bordered. The surface 15a of the process chamber wall 14 at least facing the process chamber PR is a material which is inert to the plasma activated reactive gas in the tank plant 9, preferably a dielectric material, particularly preferably the above-mentioned. It consists of one or more of the group of materials (G).

In that case, the original wall 14 forming the process casing inside the vacuum vessel with the wall 1 can be made of the material forming the surface 15a, or the inert material forming the surface 15a It is fabricated as, for example, laminated on a support wall (not shown) facing the wall 1, the latter being made of stainless steel or inox because it is not exposed to the process chamber PR. The process chamber PR is vacuum pumped by the pumping connection line 11 or the pump 13 to the residual gas partial pressure described in connection with FIG. 1, while the vacuum vessel wall 1 and The intervening space ZW between the casings 14 is vacuum pumped by the same or different vacuum pumps, for example via separate pumping connection lines 11a.

Those skilled in the art will appreciate that a suitable throttling mechanism, which can be controlled when using the same pump 13 to vacuum pump both spaces, namely the process chamber PR and the intervening space ZW, is incorporated in the double speed pump connection line 11 or 11a. You will see right away. For the low energy plasma used to carry out the method according to the invention in the module according to FIG. 2, the assumptions already made in relation to the module described in FIG. 1 apply. The process chamber casing formed by the wall 14, provided in the embodiment according to FIG. 2, is preferably formed in the container 3a so as to be exchangeable.

3 shows a process module of type II _{e in} a view similar to that of FIGS. 1 and 2, which type of process module surrounds the process chamber PR when compared to the process module shown in FIG. 2. It only differs in that the wall 14a is made of stainless steel, inox, or other metal, like for example the wall 1, without satisfying the inertness requirements described in connection with the process module according to FIG. 2. Regarding the setting of the residual gas partial pressure, the ion energy in the substrate support zone corresponds to the values described with respect to FIGS. 1 and 2, and the wall 14a, which is usually metallic, can also be exchanged so that the process module according to FIG. Type II _e can be retrofitted immediately into process module type I according to FIG. 2 and vice versa.

According to the invention, the structure of the process module according to FIGS. 1 to 3 is independent of the process carried out in the process module.

In Fig. 4 another process module type II _ne which is not according to the invention is also shown in a view similar to Figs. Unlike the process module described with reference to FIGS. 1 to 3, in such type II _ne the process chamber is bound to the process chamber wall 1 as a surface made of stainless steel or inox, for example. However, when using such a process module in accordance with the present invention in its structure, i.e. performing the method according to the invention by the process module or using such a module in the scope of the method according to the invention, In the setting of the residual gas partial pressure and the plasma, the content already described for Types I and II is applied as it is.

It can be seen immediately that module types I, type II _e and type II _ne can be retrofitted with one another by removing or inserting the corresponding chamber casings 14 and 15b.

5 shows a preferred embodiment of the process module type I according to FIG. 2. In that regard, it is to be mentioned that all measures in the basic module, starting from the module according to FIG. 2, additionally or specifically preferably used in addition to the module according to FIG. 5, can be used individually or in any combination. .

Process module type I in the preferred embodiment shown in FIG. 5 can be retrofitted to module type II _e or module type II _ne as shown. The vessel wall 10 of the process module according to FIG. 5, preferably made of stainless steel or inox, preferably has an electron source 105 causing plasma discharge in the process chamber PR, preferably at the center of the top plate 103. Equipped. Other plasmas, such as, for example, microwave plasmas, may also be used provided they are within the range of ion energy in the substrate support zone which is basically required according to the invention, but preferably electrons having an electron energy of 100 eV or less, preferably 50 eV or less An electron source such as emitting electron source 105 is used. In that case, in the preferred embodiment, the plasma discharge is implemented as a DC discharge. The electron source 105 according to FIG. 5 is a cathode chamber 109 formed by a thermal ion cathode, preferably a direct heating thermal ion cathode 107 and having a cathode chamber wall electrically insulated from the container walls 101, 103. It is preferable to be built in). The cathode chamber is in communication with the process chamber PR via the discharge port 111. In particular, in order to protect the thermal ion cathode 107 from the reactive gas in the process chamber PR and to enable high electron emission, it is preferable that a working gas such as, for example, argon flow into the cathode chamber 109 (not shown). skip).

The process chamber casing 113, which is spaced apart from the container walls 103 and 101 and fixed with the intervening space ZW, surrounding the process chamber PR, is preferably assembled to be interchangeable similarly to FIG. 2. Here, not only the process chamber PR in the casing 113 but also the intervening space ZW are pumped via the same pumping connection line, and in some cases, a different pumping cross section has an intervening space on one side from the connection line 115. ZW, on the other hand, is guided to the process chamber PR, respectively.

In the process chamber PR, a positive electrode device works. Such anode device is preferably formed by two or more anodes 117a or 117b disposed concentrically on the outlet axis A as shown in FIG. 5. The anodes may be induced at ground potential or anode potential separately from one another (not shown), and such potentials may also be set separately from each other. More preferably, a reference potential, preferably a ground potential, is applied to the container walls 101, 103. In addition, the anodes 117a and 117b, which are spaced along the outlet axis A, may be electrically driven separately from each other, and may preferably be heated or cooled separately from each other (not shown). This is done by directing a tempering medium line to the anode and / or by embedding a heating spiral in the anode.

In Fig. 5, the plasma beam PL generated by the plasma generator which is preferably used is shown by a dashed-dotted line, where the plasma density distribution V drawn purely as found is coaxial with the outlet axis A. Shown together as a phase. By appropriately driving the anodes 117a and 117b to the anode potential or controlling the temperature of the anode to be controlled, the plasma density distribution V can be set as intended.

During the process chamber PR, the wafer holder 119 may be assembled, or the wafer holder 119 may be introduced to be controlled into the process chamber PR as will be described later. In order to preferably treat the disk-shaped workpiece 120, the substrate holder 119 forming the support surface 119a is parallel to, inclined with respect to the outlet axis A, by the support surface 119a, or Although it is of course possible to provide a vertical but eccentric with respect to it as shown in FIG. 5, the wafer holder 119 is disposed concentrically with the axis A of the discharge port 111 as its support surface 119a. It is by far preferred. The wafer holder 119 may enter or exit from the receiving opening 123 formed through the process casing 113 by the external drive device 121 as indicated by the double arrow "F". When the wafer holder 119 is fully moved upward by the drive device 121 toward the process chamber PR, the edge portion 125 of the wafer holder 119 is at least partially so that the loading support does not escape from the process chamber PR. The open opening 123 of 113 is closed.

The above-described workpiece or part to be processed, which is preferably disk-shaped, is laid down on the fixed receiving support 126 via the slit valve 129 while the wafer or workpiece support 119 is lowered. After that, the wafer holder 119 is lifted up and engaged by the support surface 19a under the workpiece or wafer 120, and lifted it from the fixed support 126 to move up into the process chamber PR. On the other hand, when the machining position is reached, the process chamber PR is closed with the edge surface 125 to the extent described above.

The support 126 is assembled to the workpiece temperature control device 127, and the temperature control medium is propagated through the temperature control medium supply and discharge lines 128. Typically, the introduced substrate 120 is heated by the plate 128a. In Fig. 5, the wafer holder 119 is shown in its processing position by a dashed-dotted line.

The vessel wall 101 and its end side closure plates 103 or 131 are temperature controlled. Preferably it is cooled. For that purpose, the wall 101 forming the casing is formed as a double wall with a temperature control system embedded therebetween. The end plate 103 or 131 is also assembled with a temperature control medium line system.

Outside the vacuum vessel, a Helmholtz coil 133 and a divided deflection coil 133 are assembled. By the Helmholtz coil 133, a magnetic field pattern is generated in the process chamber PR that is substantially parallel to and symmetrical about the axis A. FIG. Such magnetic field pattern is moved by the deflection coil 135 in a plane perpendicular to the axis A, as schematically shown in FIG. 6. As the magnetic field intensity distribution H _A is moved as such, the plasma density distribution V in the substrate attached to the substrate support 119 is changed. Thereby, a relative movement between the plasma density distribution V and the surface of the workpiece to be processed on the substrate support 19 is obtained, which is similar to the movement of the substrate with respect to a plasma with a constant plasma density distribution over time. Do. Such magnetic field distribution control results in an effect on the substrate as though the substrate is mechanically moved relative to the plasma despite the absence of mechanical movement of the substrate.

The reactive gas is introduced into the process chamber PR via the reactive gas inlet device 137. As shown, the reactive gas inlet device is preferably disposed coaxially with the axis A in the immediate region of the substrate 120 or substrate support 119 placed in the machining position and is approximately parallel to the substrate surface to be treated. It has one inlet opening.

As mentioned above, the vacuum vessels 101 and 103, preferably made of stainless steel, are concentrated cooled. It is to meet UHV condition. In that case, such intensive cooling prevents the heating of the steel during the process and the accompanying release of carbon containing gas from the steel.

For the process chamber casing 113, in particular the material of its surface exposed to the process, the content already described with reference to FIG. 1 is applied as it is: an inert material, preferably a dielectric material and a material group G as described above. The material selected from is stable at high process temperatures, in particular hydrogen, silane, germane, diboran, chlorine, NF ₃ , HCl, SiH ₃ CH ₃ , GeH ₃ CH ₃ , N ₂ , It does not form gaseous compounds by combining with working gases such as ClF ₃ , PH ₃ , AsH ₄ . In this way, it is realized not to contaminate the component 120. Coating impurities on the inner surface of the process chamber casing 113 is important only in the aspect in which the particles are formed. Thin coating of impurities can be highly desirable to ensure a better process cleanliness, in which case the process is actually surrounded only by materials unique to the process.

In process module type I, impurities are not coated on the vacuum vessel wall, which is usually made of stainless steel, because it is protected from gas and plasma by the process chamber casing 113, as well as an intensive cooling system as shown in FIG. This is because the sediment coming out of the gas phase there is greatly reduced. The same applies to the process chamber interior surface as it applies to the surface of the substrate holder 119 exposed to the process.

The process chamber casing 113 is preferably formed of multiple parts (not shown) so that the process casing 113 can be removed or replaced without disassembling the anode devices 117a and 117b. A preferred embodiment of process module type II _ne is realized by removing the process chamber casing 113 shown in FIG. 5, or the process module type II _e according to FIG. 3 by replacing the process casing 113 with a metal casing of the same type. Will be implemented.

Hereinafter, the method performed by each process module introduced based on FIGS. 1 to 5 will be described collectively.

Type Ⅰ

Using this process module, coating is carried out by a plasma-promoting reaction while maintaining the quality requirements required when the part is coated with an epitaxial layer, or by a plasma-promoting reaction which is etched or etched up to a predetermined penetration depth. Material composition changes are made or the surface of the workpiece or part is cleaned, in particular in a hydrogen plasma, in particular in combination with the process steps according to the invention described above. Such a process module type I is not introduced into the workpiece component therein or is self-adjusted as required or after a given number of the aforementioned processing steps have been carried out using a substrate model. Such midnight comprises, on the one hand, an etching step by a plasma promoting reaction, and on the other hand, followed by a step of washing the etching residue by the plasma promoting reaction, preferably in a hydrogen plasma.

Type II

Process module type II is used for cleaning deeper into the workpiece as required, for example when it is provided from the ambient atmosphere to a processing step that meets the epitaxial quality requirements described above. In such process module II also by means of the low energy plasma reaction described above in combination with a treatment process that also satisfies the maximum quality requirements described above, preferably by first etching by means of a plasma promoting reaction and subsequent by a plasma promoting reaction, preferably The parts are cleaned by washing in hydrogen plasma.

As a preferred coating method, i.e. depositing a hetero or homo epitaxial layer by process module type I, full reference is made to the measures according to WO98 / 58099 already mentioned earlier.

7 schematically shows a process module of type I or type II. During the operation, the component to be processed 142 is sequentially supplied to the process module 140, or the processed component 142 is sequentially removed from the process module. On the time axis t shown in FIG. 7 purely illustratively the coating step and / or the etching step and / or the material composition change step and / or the cleaning step according to the invention in the part 142 are shown in shaded. Then, after necessity or after a predetermined number of such processing steps, the steps of self-cleaning (not hatched) the module 140 coated with impurities during the course of the operation are followed by their respective steps.

8 shows, for example, the starting material in the vacuum atmosphere of a plant 144, such as an in-line plant, starting from process module type II, followed by a coating step, an etching step, a material composition change step, and a case in process module type I. In some cases, the treatment is also performed in a washing step. The process module provided is then also self-cleaning after a given number of processing cycles, similarly as in FIG. 7.

As already mentioned above, it is preferred that such type of process is the manufacture of a virtual substrate. According to him, in process module type II, a base suitable solely for growing a hetero epitaxial layer is cleaned by a plasma promoted reaction with the use of halogen as the reactive gas, preferably hydrogen. Subsequently, in one or more subsequent process module types I, the heteroepitaxial layer is grown such that the lattice constant is changed and the maximum gradient free surface structure is obtained by continuous gradient replenishment of additional material. Then, if desired, again in another process module type I, the semiconductor layer is mechanically clamped as previously given for the setting of strip spacing and the setting of desired semiconductor properties, for example the mobility of the charge carriers. The semiconductor layer to be used is grown. Subsequently, further processing steps according to the present invention are carried out as needed until the completed virtual substrate exits the facility 144.

As is well known to those skilled in the art, even when fabricating a virtual substrate, additional layers may be attached or a cleaning step may be provided between the coating steps, in which case the cleaning step is a "soft cleaning step" in Process Module Type I. Preferably provided as.

FIG. 8 is a schematic but "inline" installation in which workpiece transfer from module to another module takes place approximately linearly in a vacuum.

9 shows in plan view a preferred arrangement of a plurality of process module type I and process module type II as respective clusters belonging to a cluster installation. Such cluster facilities include a circular vacuum transfer chamber 150 that manipulates the process module in approximately radial directions. The unprocessed substrate is pulled out of the gate chamber 152 and the processed substrate is put there, the latter being cooled there for example. From the entrance gate chamber 152 provided by way of example, the substrate is removed from the unprocessed substrate storage magazine 156 by the robot unit 154 placed in a normal atmosphere, or the processed substrate storage magazine 158 is completed. Supplied. Such equipment is controlled over time by program control. For example, it can be freely programmed.

The above-described process modules, which can all be adapted to each other, can process substrates with a diameter of at least 150 mm, preferably at least 200 mm and very preferably at least 300 mm. In the case of epitaxy coating by the method disclosed in the aforementioned WO98 / 58099, which is attached as an appendix in the disclosure of the method of the present application, a coating rate of 60 nm / min is obtained for the above-mentioned substrate.

The appendix will be described below.

Method for producing a workpiece to be coated, use of the method, and equipment therefor

(Specifications at the beginning of Appendix "A" PCT / CH98 / 00221)

The invention relates to a process for producing a workpiece to be coated according to the preamble of claim 1, to its use according to claims 28 to 35, to an installation for carrying out the method according to the preamble of claim 36, and to It relates to the use of the equipment.

In this regard, the present invention starts from the problem that occurs when the thin layer is produced by the CVD method and the PECVD method. What is recognized in accordance with the present invention for such a problem can be dedicated to fabricating semiconductor layers, in particular in solar cell fabrication or in modulation doped FETs or heterobipolar transistors.

The semiconductor thin film is also deposited in monocrystalline form, ie epitaxially, on a single crystal substrate, such as a silicon substrate, or otherwise in polycrystalline or amorphous form, on a polycrystalline or amorphous substrate, for example on glass. While the invention is described above in connection with substrates that are silicon and / or germanium coated, among other things, the invention may also be applied to workpieces coated with other substrates and other materials, as described above.

Known methods for depositing epitaxial semiconductor films are as follows:

Molecular Beam Epitaxy, MBE (Molecular Beam Epitaxy)

-Thermochemical vapor deposition, chemical vapor deposition (CVD)

-Remote plasma accelerated CVD method by DC discharge or high frequency discharge, RPECVD (Remote-Plasma-Enhanced CVD)

Microwave plasma promoted chemical vapor deposition and electron / cyclotron resonant plasma assisted CVD, ECRCVD (Electron-Cyclotron-Resonance-Plasma-Assisted CVD).

The CVD method is a general concept of a number of thermal deposition methods which are distinguished by the structure of the accessory device or by the type of operation thereof. That is, for example, the CVD method may be performed at normal atmospheric pressure, or may be performed in an ultrahigh vacuum region of very low pressure or less. For that matter, reference may be made to the documents (1) and (2) in the accompanying literature list.

Only CVD is commonly used in the commercial production of epitaxial Si layers. In that case, the reactive gases used are, for example, silicon containing gases such as chlorosilane, SiCl ₄ , Si ₃ HCl, and SiH ₂ Cl ₂ and silanes such as SiH ₄ or Si ₂ H ₆ . Specific to standard CVD methods are high deposition temperatures on the order of magnitude above 1000 ° C. and pressures typically between 20 mbar and 1000 mbar, ie up to normal atmospheric pressure.

Thereby, the coating speed of several micrometers per minute corresponding to several 100 mW / sec is obtained according to process conditions, About this, reference also to literature (1).

On the other hand, low pressure chemical vapor deposition (equivalent to LPCVD, Low-Pressure Chemical Vapor Deposition, LPVPE, and Low-Pressure Vapor Phase Epitaxy) is done at less than 1 mbar and typically lower process temperatures up to 700 ° C. Allow. In addition, reference may be made to Documents (1) and (3) and (6).

Referring to Document (6) for LPCVD, at a deposition temperature of 650 ° C.

GR = 50 mW / min

The growth rate of is given. In that case, the reactive gas flux to the silane

F = 14 sccm

to be. From there, the characteristic number associated with the gas yield, ie the growth rate GR _F per unit of reactive gas flux,

GR _F = 3.6 Å / (sccmmin)

Will come out. Area converted from the actual area A ₂ for the 2 "wafer

A ₅ = 123 cm 3

For 5 "wafers, the growth amount GA

GA = 5.2 · 10 ¹⁶ Si-atom / sec

Is given by Again, with respect to reactive gas flux units, the characteristic number "deposition amount per reactive gas flux unit" GA _F , also referred to as "gas utilization number"

GA _F = 8.410 ^-3

, Which corresponds to 8.4 ‰.

At 650 ° C., an epitaxial layer is produced.

When the deposition temperature drops to 600 ° C., a polycrystalline layer is produced. Such polycrystalline layer has the following values:

GR = 3 Å / min

F = 28 sccm silane

GR _F = 0.11 μs / (sccmmin)

GA = 3.110 ¹⁵ Value for Si-atom / sec, A ₅

GA _F = 2.5 · 10 ^-4 , equivalent to 0.25 ‰.

Basically, the following criteria are required for defect-free epitaxial layer growth:

-Transmission electron microscopy of the cross-sectional preparat is performed to verify epitaxy by electron diffraction and high resolution,

In that case typically no defects should be visible in the range of 10 to 15 μm, which can be transmitted along the interface with the substrate. Typical magnifications in defect analysis are 110'0000 to 220'000.

Even more advanced is Ultra High Vacuum Chemical Vapor Deposition (UHV-CVD) with a working pressure in the range of 10 ⁻⁴ to 10 ⁻² mbar, typically 10 ⁻³ mbar, as described in literature (4), 5) and document (7). Such ultra-vacuum chemical vapor deposition allows very low workpiece temperatures, but very low growth rates or coating rates. That is, according to document (5), its growth rate or coating rate is about 3 dl / min at 550 ° C. for pure silicon.

The reason for the low growth rate is that the more hydrogen is covered on the surface of the workpiece, the slower the absorption and cleavage rate of the reactive molecules, ie, SiH ₄ . That is, layer growth is limited by the desorption rate of H ₂ , which desorption rate increases exponentially with temperature. Reference may be made to Document (8). Since the bond energy of the Ge—H bonds is small compared to the Si—H bonds, hydrogen desorption from the Si—Ge alloy surface is greater, resulting in higher growth rates than with pure Si even at the same substrate temperature. For example, at a Ge content of 10%, the growth rate is about 25 times larger at 550 ° C. (see Document (5)).

Another way to achieve high deposition rates with epitaxy quality at low substrate temperatures (see Document (9)) is to decompose the reactive gas by microwave plasma (ECRCVD).

By using a plasma source based on the principle of electron / cyclotron resonance, high energy ions are avoided from entering the substrate.

Such plasma sources are typically operated in a pressure range of 10 ⁻³ to 10 ⁻⁴ mbar, but this results in longer free path lengths than in the case of capacitively coupled high frequency plasma. This in turn results in undesirably ion bombardment of the substrate resulting in defects, as can be seen from Document (10). However, the energy of the ions impinging on the substrate can be limited by controlling the external potential of the substrate from the outside, thereby greatly avoiding damage by the ions. Even with ECRCVD, the growth rate for pure silicon is only a few 10 mW / min at low deposition temperatures of ≤ 600 ° C.

In summary, this results in:

The layer deposited in a quality suitable for depositing the epitaxial layer is present at a deposition temperature of ≤ 600 ° C.

By UHV-CVD with a growth rate GR of about 3 μs / min or

ECRCVD with a growth rate GR of approximately 1 digit (30 Å / min)

Can be deposited by.

The PECVD method of generating the plasma by DC discharge is not intended to constitute an epitaxial layer nor to constitute an amorphous or polycrystalline layer, but a layer of epitaxy quality, i.e. corresponding defect density (see above). The low layer cannot be used at least with the growth rate GR, reliability, and effectiveness or efficiency desired to be secured for industrial production.

The use of a capacitively coupled high frequency magnetic field for generating a high frequency plasma in a PECVD method has already been reported earlier, which can be found in the literature (11). The difficulty with such measures is that only reactive gases do not decompose in such high frequency plasmas. At the same time, the substrate surface is heavily bombarded by high energy ions as are specifically used even during reactive atomization or high frequency etching. It promotes hydrogen desorption on the one hand but at the same time results in defects in the grown layer. An alternative method, RPCVD, remote plasma chemical vapor deposition takes account of such drawbacks by avoiding direct exposure of the substrate to be coated to high frequency plasma, leading to good results (see Document (12)). However, the growth rate obtained is small. That is, according to document (13), most are in the range of nm per minute to several nm per minute.

It is an object of the present invention to provide a method applicable to industrial manufacture, which is capable of growing a layer having epitaxy quality at a higher growth rate than so far known.

Such an object is achieved by a method of the type mentioned at the outset which is characterized in accordance with the intent of the features of claim 1 or by means of an installation characterized by the features of claim 36. Preferred embodiments of the method are specified in claims 2 to 27, and preferred embodiments of the installation are specified in claims 37 to 50. In particular, the process according to the invention comprises an epitaxial layer, an amorphous layer, or a polycrystalline layer, in particular an epitaxial layer, an amorphous layer, or in particular a Si layer, a Ge layer, or a Si / Ge alloy layer and a Ga layer or a Ga compound layer. It is particularly suitable for making substrates which are semiconductor coated with polycrystalline layers.

In that case, in particular, a doped semiconductor layer may be deposited. Preferably a silicon and / or germanium containing layer doped with one or more elements from group III or group V of the periodic table or one or more elements from group II, III, IV, or VI of the periodic table, such as Mg or Si Potassium containing layer doped with can be deposited.

Summarizing from the coating technique covered at the outset of creating an epitaxial layer, it can be explained as follows:

CVD methods, especially UHV-CVD methods, result in excellent layer quality even at substrate temperatures below 500 ° C. As such, such a method would also be provided for producing epitaxial layers with very stringent requirements on layer quality. In such a method, however, the growth rate, for example, the growth rate for Si, is very low, as described above, at 3 Å / min at 550 ° C.

Microwave plasma promotion method, ECRCVD, has the advantage that reactive molecules can be decomposed without high thermal energy. Due to ion bombardment of the substrate, high hydrogen desorption occurs. These two effects can lead to a noticeable increase in growth rate. At low temperatures, however, unacceptable defect densities caused by ion bombardment are observed. Although the layer quality is improved by controlling the substrate bias voltage, there is no way to change the relatively low speed.

It is believed that there is an inherent contradiction: ion bombardment of the substrate, on the one hand, results in a high growth rate based on increased hydrogen desorption, but at the same time causes an increase in defect density.

According to document (2), the following aspects are given for the thermal CVD method operating under atmospheric pressure:

Si growth rate GR: 2 × 10 ^-3 nm / min

(3 · 10 ^-2 ㎚ / min measured at 600 ℃ converted to 550 ℃)

Gas flux, SiCl ₂ H ₂ , F: 100 sccm.

From there, the growth rate GR per unit of SiCl ₂ H ₂ flux is GR _F It is given as 2 x 10 ^-4 mm 3 / (sccm · min).

The gas flux F of 100 sccm SiCl ₂ H ₂ corresponds to 4.4 × 10 ¹⁹ molecules / sec.

A growth rate GR of 2 × 10 ⁻³ nm / min corresponds to a growth rate of 2 × 10 ⁻⁴ silicon mono-layers per second on a 5 ″ wafer corresponding to an area A ₅ of 123 cm 3. Per second in the area of

GA = 1.7 × 10 ¹³ silicon atoms / sec

The amount of deposition of is given.

By correlating the second reactive gas inflow amount and the deposited silicon per second, the number of gas utilization GA _F

GA _F = 3.9 × 10 ^-7

Given by

That corresponds to a utilization of about 0.0004 ‰.

At atmospheric CVD, it was confirmed that:

GR _F 2 × 10 ^-4 Å / (sccmmin)

GA _F 0.0004 ‰.

Estimating for UHV-CVD from Document (5) in combination with Documents (4) and (7) gives:

GR _F 0.1 Å / (sccm · min)

GA _F 0.0035, equivalent to about 35 ‰.

It is a method of manufacturing layers with epitaxy quality, which until now has been intended for industrial application.

In addition, a PECVD method using DC glow discharge in the form of low voltage discharges is known from DE-OS 36 14 384. By such a method, layers with very good mechanical properties, that is, with high growth rates, are deposited.

The cathode chamber provided with the thermal cathode communicates with the vacuum vessel via the discharge port. The anode is provided opposite the outlet. The inflow device of the reactive gas is provided in parallel with the discharge axis formed between the discharge port and the anode, and the workpiece is disposed to face the inflow device on the basis of the discharge axis. A discharge voltage U _AK of less than 150 V is applied to the anode potential, and the discharge is driven with a current intensity I _AK of 30 A or more. For coating, the workpiece is at a negative potential of 48 to 610 V.

The tests disclosed in that publication provide the following aspects:

Example GR [Å / min] GR _F [Å / (sccm · min)]

1 10 ³ 2.5

2 380 1.2

3 2 × 10 ³ 2.5

4 (Si) 166 0.7

5 466 1.2

6 750 0.7

7 250 0.5

Example GR [Å / min] GR _F [Å / (sccm · min)]

8 500 0.75

9 316 0.38

10 344 0.18

11 62 0.18

12 58 0.14

The present invention now contradicts the expectations brought to date by using a non-microwave plasma PECVD method, i.e. a PECVD method by DC discharge, in particular by using a PECVD method as known in DE-OS 36 14 348 in its principle. It starts with the recognition that the workpiece can be coated with such layer quality that meets the requirements required for the epitaxial layer.

In that case, as disclosed, epitaxy quality

a) growth rate of at least 150 Å / min, in particular at least 600 Å / min GR

b) it is possible to obtain a GR _{F of} at least 7.5 dL / (sccm · min) or in particular at least 40 dL / (sccm · min), preferably at least 75 dL / (sccm · min)

c) It is possible to obtain a gas utilization number GA _F over a range of 5%.

In the DC-PECVD chamber used according to the present invention, low energy ions are generated by the plasma discharge, and it is confirmed that the charged carrier density, especially the electron density, is very high in the discharge applied while the low energy electrons are generated.

Hereinafter, the present invention will be described by way of example with reference to the accompanying drawings. Among the accompanying drawings,

1 shows schematically a first preferred embodiment of a plant according to the invention for carrying out the method according to the invention;

2 shows a schematic representation of a second preferred embodiment of the installation according to FIG. 1 involving a number of deformation operations;

3 is a graph showing the dependence of the growth rate on the wafer temperature upon operation of the plant according to FIG. 2 for silicon coating;

4 is a graph showing the increase in growth rate associated with reactive gas flux GR _F as a function of discharge current;

5 is a graph showing growth rate as a function of reactive gas flux when the plasma density in the zone of the workpiece is different;

6 is a graph showing growth rate as a function of germanium concentration in the deposited layer;

7 is a graph showing the growth rate / gas utilization water compartments of the prior art and the results according to the invention.

Firstly, a facility according to DE-OS 36 14 384 can be used solely to carry out the method according to the invention as long as it is operated to maintain the conditions according to the invention.

According to FIG. 1, the presently preferred apparatus for carrying out the method according to the present invention includes a vacuum container 1, in which a cathode chamber 5 is flanged via a discharge port 3. Potential of the container 1 may be applied to the cathode chamber 5 in a known manner, or a potential other than that may be applied while the cathode chamber 5 is insulated from the container 1 (shown in FIG. skip).

In the cathode chamber 5, a thermal cathode 7, ie a filament, is provided and is preferably directly heated by the heating current generator 9.

In the discharge port axis A, the workpiece support 13 insulated and assembled facing the discharge port 3 is provided in the container 1. The workpiece heating device 17 may be provided in the zone of the workpiece support 13. The vessel 1 is vacuumed by a vacuum pump 27, preferably a turbo vacuum pump, more preferably a turbo molecular pump. For example, a sensor, such as a plasma monitor, can be provided in the connection line 31 for observation and optionally for control.

The gas injection ring 23 is provided as a reactive gas injection device coaxially with the axis A of the discharge having the discharge current I _AK , and is connected to the gas tank device 25 for the reactive gas, the reactive gas being a controllable flux. Flows into the vessel at F (sccm). For example, a connection line 6 leading to a working gas tank containing Ar is through the cathode chamber 5. By means of the electromagnet and permanent magnet device 29 a magnetic field B is generated in the container approximately concentric with the axis A, in particular acting even in the region of the discharge port 3. In that case, it is desirable that such a magnetic field can be moved away from concentricity.

The installation of the embodiment according to FIG. 1 works as follows:

The container wall corresponding to the reference "1" is used as the anode of the discharge, for which the container wall is subjected to a reference potential, and preferably the container wall is connected to ground as shown. Correspondingly, a negative potential is applied to the cathode 5 by means of an adjustable DC generator 11. The discharge voltage U _AK is applied across such a generator 1 so that the discharge current I _AK flows between the cathode 7 and the container 1.

- it will take a second modified operation voltage U _s to the workpiece support (13) by a DC bias generator 15. In the plant shown in Fig.

In figure 2 there is shown another preferred arrangement according to the invention for carrying out the method according to the invention. The same reference numerals are used for the same parts as in FIG. The plant according to FIG. 2 is distinguished from the plant shown in FIG. 1 in the following respects and will be described later.

A ring-shaped auxiliary anode 19 arranged concentrically on the discharge axis A is provided.

In the installation according to FIG. 2 the following work forms are possible:

As shown by the variable switch S, the vessel wall of the vessel 1 is subjected to a reference potential or a ground potential as already described in FIG. 1 or the vessel wall is an impedance element 14, preferably a resistor. Either it is fixed at a constant potential, preferably a reference potential, via the element, or the potential is operated to vary. When the reference potential is applied to the container 1, the potential of the container is applied to the auxiliary anode 19, or a voltage is preferably applied by the adjustable DC generator 21.

When the vessel 1 is fixed at the reference potential via the impedance element 14, the auxiliary anode is operated by the DC generator 21, as shown by the dotted line between the cathode 7 and the auxiliary anode 19. The discharge voltage U ' _AK is shown. This is also the case when the container wall 1 is operated in such a way that the potential is varied.

At present, the installation according to FIG. 2 is preferred, in which the vessel wall and auxiliary anode 19 are grounded and the workpiece support 13 is operated in a potential controlled manner. For all plant types, the following settings are important:

Total pressure in the container P _T :

10 ^-4 mbar ≤ P _T ≤ 10 ^-1 mbar, preferably

10 ^-3 mbar ≤ P _T ≤ 10 ^-2 mbar,

Typically, it is in the range of 5 · 10 ⁻³ mbar. Such a pressure is ensured, among other things, by the partial pressure of the working gas, preferably argon. Therefore, the vacuum pump 27 is preferably formed as a turbo vacuum pump, in particular, as a turbo molecular pump, as described above.

Working gas pressure P _A :

It is chosen as follows:

10 ^-4 mbar ≤ P _A ≤ 10 ^-1 mbar, preferably

10 ⁻³ mbar ≦ P _A ≦ 10 ⁻² mbar.

Reactive gas partial pressure P _R :

It is preferably chosen as follows:

10 ^-5 mbar ≤ P _R ≤ 10 ^-1 mbar, preferably

10 ⁻⁴ mbar ≦ P _R ≦ 10 ⁻¹ mbar.

In particular, partial pressures of 10 ⁻⁴ mbar to 25 · 10 ⁻³ mbar are recommended for silicon and / or germanium containing gases. First of all, in order to support flatness (surface roughness) for multilayer deposition and doped layers, it is recommended to further provide hydrogen partial pressures on the order of 10 ⁻⁴ to 10 ⁻² mbar, preferably about 10 ⁻³ mbar. .

Gas flow:

Argon: greatly depends on the vessel volume and the cathode chamber volume for the setting of the required partial pressures P _A to P _T.

Reactive gas flux: 1 to 100 sccm, in particular for gases containing silicon and / or germanium

H2: 1 to 100 sccm.

Discharge Voltage U _AK :

The discharge voltage is either between the cathode 7 and the vessel 1 according to FIG. 1, between the cathode 7 and the vessel 1 and the auxiliary anode 19 or between the cathode 7 and the auxiliary anode 19. Which is set as follows:

10 V ≤ U _AK ≤ 80 V, preferably

20 V ≦ U _AK ≦ 35 V.

Discharge Current I _AK :

It is chosen as follows:

5 A ≤ I _AK ≤ 400 A, preferably

20 A <I _AK <100 V.

Workpiece Voltage U _s :

The voltage is chosen at any rate below the sputtering limit of the discharge. In all cases it is set as follows:

-25 V ≤ U _s ≤ +25 V,

For Ga compounds, suitably SI, Ge, and compounds thereof

-20 V ≤ U _s ≤ +20 V,

Such voltage is preferably negative, of which it is preferably set as follows:

-15 V ≤ U _s ≤ -3 V.

Current density at the workpiece surface to be coated:

Such current density is measured in advance by a probe installed at the point where the surface to be coated will later be located. It is set from 0.05 A / cm 3 or more, preferably 0.1 A / cm 3 or more, up to the discharge current / substrate area with respect to the probe surface.

Such current density is measured and set as follows:

One or more probes are later placed at the point on the surface to be coated and a positive voltage applied to the surface is varied with respect to ground or anode potential. Raise the voltage until the measured current no longer rises. The total current density for the probe surface is then derived from the measured current value. Now, such a current density is set to the value required by the control of the discharge. Setting the above-described current density value is preferably possible by setting the discharge current value I _AK to 5 to 400 A, preferably 20 to 100 A.

The high flux of low energy ions and electrons incident on the workpiece is a particular feature of the method according to the invention, thus abbreviating the method according to the invention to "Low Energy Plasma Enhanced CVD". Referred to as LEPECVD.

During the coating, the silicon and / or germanium layer is n-type conductive layer or p-type by adding a dopant gas containing elements from periodic table Group III or Group V such as phosphine, diborane, arsine Can be doped with a conductive layer. Thus, p / n semiconductor transitions can be economically made on site, for example for solar cell manufacturing.

When depositing a gallium layer or a gallium compound layer, the layer may be doped by the use of a dopant gas containing elements from the periodic table of Groups II, III, IV, or VI, such as Mg or Si.

The low voltage reversal may be focused by the anode 19 and / or the magnetic field B and / or deflected from the workpiece support 13. This allows to increase the plasma density at the workpiece support (increase the growth rate) and / or to change (set distribution) over a wide range, or to sweep or deflect it in a controlled manner. The workpiece or substrate may be heated by the heating device 17 up to about 800 ° C. irrespective of ion incidence and / or electron incidence. The magnet device 29 generates a magnetic field B in the discharge chamber by means of permanent magnets and / or electromagnets, preferably at a magnetic flux density of several tens to several hundred gauss.

According to document (15), as described above, a discharge plasma potential close to the anode potential is given based on an unusually low discharge voltage preferably in the range of 20 to 35 V. The workpiece or substrate potential can be easily adjusted in potential so that the ion energy lies below 15 eV, so that damage by ions during layer growth in the workpiece can be completely avoided.

As mentioned above, efforts should be made to obtain as high a plasma density as possible in the workpiece. In this case, the plasma density is given by the current density at the workpiece surface. Such current density is measured and set by the probe during the calibration operation as described above.

Although the installation as schematically shown in FIGS. 1 and 2 is a presently preferred embodiment, it is possible to fully implement the method according to the invention, for example in the installation disclosed in DE-OS 36 14 384, if it is correspondingly installed and derived. have.

By means of the equipment shown schematically in Fig. 2, the 3 "silicon single crystal substrate was epitaxially coated with silicon or a silicon / germanium alloy.

The plant worked as follows:

Applying the potential of the container 1 to the auxiliary anode 19; The controlled bias potential is applied to the workpiece support 13. A ground potential is applied to the container as the anode.

The working point was set as follows:

Workpiece temperature T _s

It is guided by the plasma and results in a workpiece temperature of only a few hundred degrees Celsius, ie 150 degrees Celsius.

It is very advantageous for coating thermally hazardous substrates such as organic substrates.

Higher desired temperatures are obtained by separate heating devices. When preparing a Si layer and / or a layer containing a Ge layer and a Ge-Si compound, the workpiece temperature T _s is

300 ℃ ≤ T _s ≤ 600 ℃

Is recommended, and when manufacturing a Ga layer or a Ga compound layer

300 ℃ ≤ T _s ≤ 800 ℃

It is recommended to do this.

Since the method is a "low temperature" method, the temperature is chosen to be as flexible as possible depending on the layer material and the substrate material.

Flux [sccm] Partial pressure [mbar] Ar 50 6. 8 × 10 ^-3 H ₂ 5 7 × 10 ^-4 SiH ₄ 10 10 ^-3

Discharge Current I _AK : 70 A

Discharge Voltage U _AK : 25 V

Substrate temperature: 550 ° C. (heated by heating device)

In the first test, the substrate temperature was changed by the heating device 17. In that case, the remaining work point parameters were kept constant. The results are shown in FIG. As can be seen from the figure, the growth rate GR only slightly depends on the workpiece temperature or the substrate temperature T ₁₃ . The large dispersion of the measurements is due to the manual setting of the operating parameters in the test facility before each deposition.

Starting from the work point value described above, the discharge current I _AK was changed by setting the discharge voltage U _AK and, if necessary, by changing the cathode heating current. All other parameters were kept constant as well. Although the discharge current I _AK does not directly correspond to the charged carrier density or the plasma density at the surface to be coated, if other parameters are kept constant, the plasma density corresponding to the current density at the surface of the workpiece to be coated is approximately the discharge current. Proportional to As such, the results shown in FIG. 4 show the complete proportionality and proportionality constant between growth rate GR and plasma density. Such proportionality may be interrupted while gas usage does not exceed about 60% and saturation effects occur. As mentioned above, in addition to being influenced by, for example, the control of the discharge current, the plasma density is also affected by the focusing or defocusing of the low voltage discharge or by the deflection of the low voltage discharge. Here, it is intended that the relatively large dispersion is due to the measures taken when setting the discharge conditions.

Finally, Figure 5 suggests so much. FIG. 5 is the result of a test in which the reactive gas flux F was changed starting at 10 sccm of work point while maintaining other parameters constant. The straight line a is a result of the low voltage discharge slightly shifted locally with respect to the axis A of FIG. 1 by the magnetic field setting, and the plasma density at the substrate during such discharge with the discharge current I _AK of 20 A. Is reduced or growth rate is lowered.

Curve (b) shows the growth rate when the discharge is not deflected and I _AK = 20 A. Finally, (c) shows the increased growth rate in the case of unbiased discharge with I _AK = 70 A.

When the reactive gas is 10 sccm, a growth rate of about 15 mA / sec is obtained at a substrate temperature of 550 ° C. and a discharge current I _AK of 70 A as shown in FIG. 3.

Such results when the discharge current is 70 A and the reactive gas flux is 10 sccm are also demonstrated by FIG. 4. The growth rate GR drops to about 6 mA / sec at 20 A discharge current.

The results according to the invention will now be compared with the results of known techniques.

a) Comparison with APCVD (Document (2))

From FIG. 5, for example for point P1 is given as follows:

GR 1200 Å / min, in comparison with APCVD

GR 2 × 10 ^-2 Å / min

to be.

From FIG. 5, a GR _F value of 80 μs / (sccm · min) is given for the point P1.

The corresponding value in APCVD is

GR _F 2 × 10 ^-2 Å / (sccmmin)

to be.

Calculating the gas utilization number for a 3 "substrate in LEPECVD according to the present invention, is given as follows:

GA _F 6.8 × 10 ^-2 , equivalent to about 6.8%.

In that case, it can be seen that such a gas utilization number becomes much better as the substrate area becomes larger, for example as large as 5 ".

Figure 7 shows the results for the following:

Section I: Results for APCVD, LPCVD and RPECVD

In Section II: Results for UHVCVD

In Section III: Results for ECRCVD

In section IV: results according to the invention.

Such a result is for a temperature of ≤ 600 ° C.

In that regard, it should again be emphasized that the measures according to the invention allow for coating a relatively large area, thereby further increasing the gas utilization water GA _F.

Similarly, comparing the magnitude of growth rate GR, growth rate GR _F per unit of reactive gas, and gas utilization number GA _F with corresponding values for CVD under atmospheric conditions, a significant improvement is provided in accordance with the present invention in each relationship. do. Finally, when comparing the results according to the invention with the results obtained when working the PECVD method with a low voltage discharge according to DE-OS 36 14 384, the growth rate of 1200 mA / min obtained according to the invention is surprisingly high. It is shown that the growth rate GR _F per unit of the reactive gas flux obtained according to the invention is actually significantly higher than the maximum growth rate obtained by known measures, and is actually higher by an index 2 of 10.

That is, in principle, such an improvement can be obtained by fully specifying the operating conditions in a facility such as those already known from DE-OS 36 14 384, that the layer deposited according to the invention follows epitaxy conditions in terms of defect density. Given that, it is very surprising.

It was found that when operating the plant according to FIG. 2 with a defined work point parameter as described above, interposing a single crystal substrate yielded a high quality epitaxy coating, while sandwiching an amorphous substrate at a further identified work point parameter. It was very simply verified that an amorphous coating was obtained upon loading.

In addition, in FIG. 5, the point measured when the SiGe epitaxial layer containing 4% Ge was deposited instead of the pure Si layer is written in point P2.

As can be seen already, the situation does not change even when depositing a Ge / Si alloy contrary to the above recognition in the measures according to the invention. It is demonstrated by FIG. 6 where the growth rate GR at the designated work point is expressed as a function of the% content of Ge. As can be seen from that, the growth rate hardly changes in a very wide range of the ratio of Ge to Si.

The measures according to the invention are mainly derived and confirmed based on tests on Si layers, Ge layers, or Si / Ge alloy layers or Ga layers and Ga compound layers, all of which are not doped or backed.

The measures according to the invention result in a combination of very high deposition rates at low temperatures of ≦ 600 ° C. and at the same time extremely high layer quality with very high efficiency in the layer material deposited per incoming amount of reactive gas. As such, the proposed such measures are well suited for the industrial manufacture of high quality epitaxial or other layers.

List of documents

(1) Handbook of thin-film deposition processes and techniques, ed. Klaus K. Schuegraf, Noyes Publication, New Jersey, U.S.A., 1998, ISBN N 0-8155-1153-1

(2) Atmospheric pressure chemical vapor deposition of Si and SiGe at low temperature, T.O. Sedgwick and P.D. Agnello, J. Vac. Sci. Technol. A10,1913 (1992)

(3) Submicron highly doped Si layers grown by LPVPE, L. Vescan, H. Beneking and O. Meyer, J. Cryst. Growth 76, 63 (1986)

(4) Low-temperature silicon epitaxy by ultrahigh vacuum / chemical vapor deposition, B. S. Meyerson, Appl. Phys. Lett. 48, 797 (1986)

(5) Cooperative groeth phenomena in silicon / germanium low-temperature epitaxy, B. S. Meyerson, K. J. Uram, and F. K. LeGoues, Appl. Phys. Lett. 53, 2555 (1988)

(6) Silicon epitaxy at 650-800 ° C using low-pressure chemical vapor deposition both with and without plasma enhancement, T. J. Donahue and R. Relief. J. Appl. Phys. 57, 2757 (1985)

(7) Low temperature silicon epitaxy by hot wall ultrahigh vacuum low pressure chemical vapor deposition techniques: surface optimization, B. S. Meyerson, E. Ganin, D. A. Smith, and T. N. Nguyen, J. Electrochem. Soc. 133, 1232 (1986)

(8) Kinetics of surface reaction in very low-pressure chemical vapor deposition of Si from SiH ₄ , SM gates and SK Kulkarni, Appl. Phys. Lett. 58 2963 (1991)

(9) Electron cyclotron resonance assisted low temperature ultrahigh vacuum chemical vapor depositon of Si using silane, D. S. Mui, S. F. Fang, and H. Morkoс, Appl. Phys. Lett. 59, 1887 (1991)

(10) Low-temperature silicon homoepitaxy bt ultrahigh vacuum electron cyclotron resonance chemical vapor deposition, H-S. Tae S-H. Hwang, S-J. oark, E. Yoon, and K-W. Whang, Appl. Phys. Lett. 64, 1021 (1994)

(11) Epitaxial growth of silicon from SiH ₄ in the temperature range 800-1150 ° C, WG Townsend and ME Uddin, Solid State Electron 16, 39 (1973)

(12) Homoepitaxial films grown on Si (100) at 150 ° C. bt remote plasma-enhanced chemical vapor deposition, L. Breaux, B. Anthony, T. Hsu, B. Banerjee, and A. Yasch. Appl. Phys. Lett. 55, 1885 (1989)

(13) Growth of Ge _x Si _l / Si heteroepitaxial films by remote plasma chemical vapor deposition, R. Qian, D. Kinosky, T. Hsu, J. Irby, A. Mahajan, S. Thomas, B. Anthony, S. Banerjee, A. Tasch, L. Rabenberg and C. Magee, J. Vac. Sci. Technol. A10, 1920 (1992)

(14) Low temperature epitaxial silicon film growth using high vacuum electron-cyclotron-resonance plasma deposition, S. J. DeBoer, V. L. Dalal, G. Chumanov, and R. bartels, Appl. Phys. Lett. 66, 2528 (1995)

(15) Hydrogen plasma chemical cleaning of metallic substrates and Silicon wafer; W. Korner et al., Balzers Ltd., Liechtenstein, Surface and coatings technology, 76-77 (1995) 731-737.

Claim

1. A method of manufacturing a workpiece that is coated with a quality that meets epitaxy,

A process for producing a coated workpiece, characterized in that the workpiece is coated by PECVD under the use of a DC discharge.

2. The growth rate of the coating according to item 1

GR ≥ 150 μs / min

And gas utilization

1% ≤ GA _F ≤ 90%

The manufacturing method characterized by the above-mentioned.

3. The method of paragraph 2 wherein the growth rate is

GR ≥ 300 μs / min, preferably

GR ≥ 650 dl / min, more preferably

GR ≥ 1,000 Å / min

The manufacturing method characterized by the above-mentioned.

4. The method of paragraph 3, wherein

GA _F ≥ 5%

The manufacturing method characterized by the above-mentioned.

5. The method according to any one of items 1 to 4, wherein a maximum of from 0.05 A / cm 2 or more, preferably 0.1 A / cm 2 or more when the probe is measured at the same potential at the point where the workpiece surface to be coated is later positioned. And controlling the discharge so that the current density of the furnace discharge current / substrate area is set on the probe surface.

6. The process according to 5, wherein the measured current density is produced primarily by electron incidence.

7. The discharge current I _AK according to any one of items 1 to 6, wherein

5 A ≤ I _AK ≤ 400 A

And preferably

20 A ≤ I _AK ≤ 100 A

The manufacturing method characterized by the above-mentioned.

8. The method according to any one of items 1 to 7, wherein the discharge voltage U _AK is

10 V ≤ U _AK ≤ 80 V

And preferably

20 V ≤ U _AK ≤ 35 V

The manufacturing method characterized by the above-mentioned.

9. The reactive gas partial pressure P _R in the process chamber according to any one of items 1 to 8, wherein

10 ^-5 mbar ≤ P _R ≤ 10 ^-1 mbar

And preferably

10 ^-4 mbar ≤ P _R ≤ 10 ^-2 mbar

The manufacturing method characterized by the above-mentioned.

10. The production method according to any one of items 1 to 9, wherein the discharge is used as an electron source for dissociating reactive gas, among other things.

11. The production method according to any one of items 1 to 10, wherein low pressure discharge, preferably hot cathode low voltage discharge, is used as DC discharge.

12. The method according to any one of items 1 to 11, wherein the voltage P _T is set as follows in the process chamber:

10 ^-4 mbar ≤ P _T ≤ 10 ^-1 mbar, preferably

10 ⁻³ mbar ≦ P _T ≦ 10 ⁻² mbar.

13. The production method according to any one of items 1 to 12, wherein the working gas partial pressure P _A is set in the container as follows:

10 ^-4 mbar ≤ P _A ≤ 10 ^-1 mbar, preferably

10 ⁻³ mbar ≦ P _A ≦ 10 ⁻² mbar.

14. A process according to any of the preceding claims, wherein a discharge voltage is applied between the discharge cathode and the wall of the vacuum vessel, the reference potential, preferably the ground potential.

15. The process of clause 14, wherein the workpiece is to be removed from the process chamber.

Operate at floating potential

A connection bias potential is applied to the workpiece.

16. characterized in that the method according to claim 15 wherein the material to be processed by operating the negative voltage U _s, preferably U _s ≥ -25 V, more preferably from -15 V to -3 V in the voltage U _s for the discharge voltage Manufacturing method.

17. The method according to any one of items 14 to 16, wherein an auxiliary anode is preferably provided along the discharge section in the form of a ring-shaped anode surrounding the discharge, and the auxiliary anode is preferably discharged to the discharge cathode. A production method characterized by operating at a voltage that can be adjusted to be less than or equal to the voltage.

18. The production method according to any one of items 1 to 13, wherein the discharge anode insulated and assembled in the vacuum vessel is preferably provided in the form of a ring-shaped anode.

19. The process of clause 18, wherein the workpiece is

Operate at floating potential

A connection bias potential is applied to the workpiece.

20. The method according to 19, wherein the workpiece is operated at a discharge voltage or less with respect to the discharge cathode.

21. The vacuum container wall of any of paragraphs 18-20, wherein

Operate at floating potential

A manufacturing method characterized by fixing at a reference potential via an impedance element.

22. The process according to any one of items 1 to 13, wherein the workpiece is operated at a voltage of -25 V to +25 V with respect to the discharge anode, and in the case of Ga compound, Si, Ge, or a compound thereof, Makes

-20 V ≤ U _s ≤ +20 V

And a voltage of, in particular, a negative voltage.

23. The workpiece material according to any one of items 1 to 22, which is preferably 600 ° C. or lower, Si, Ge, or a compound thereof, preferably 300 ° C. to 600 ° C., and a Ga compound. Is maintained at 300 ° C to 800 ° C.

24. The process according to any one of items 1 to 23, wherein the coating is at least 7.5 cc / (sccm · min), preferably at least 40 cc / (sccm · min), more preferably at least 75 cc / (sccm Min) min. Or more of the reactive gas plus a coating rate GR _F per unit.

25. The process according to any of the preceding clauses, wherein the desired coating rate change is carried out by adjusting the reactive gas flux in the vacuum vessel approximately proportionally thereto.

26. The method according to any one of items 1 to 25, wherein the desired coating speed change is controlled by adjusting the discharge current density approximately in proportion thereto, preferably by adjusting the discharge current and / or the discharge voltage and / or the discharge. By deflecting and / or changing the focus of the latter, wherein the latter adjustment is preferably performed electrostatically and / or magnetically.

27. The production method according to any one of items 1 to 26, wherein the workpiece is heated separately from the discharge.

28. Use of the PECVD method by DC discharge to produce an epitaxial layer.

29. Use of the method according to any one of items 1 to 17 or 28 to produce a substrate having a semiconductor layer.

30. The use of paragraph 29, wherein the substrate having a semiconductor epitaxial layer or a polycrystalline or amorphous semiconductor layer is used for producing an uncoated substrate, in particular controlled by its surface properties.

31. The process according to any of paragraphs 28 to 30, comprising at least one element from a group III and / or group V of the periodic table, preferably having a silicon layer and / or a germanium layer or a Si / Ge alloy layer. Use to prepare a substrate having such a doped layer.

32. The process of any of paragraphs 28-30, comprising a Ga layer or a Ga compound layer, preferably doped with one or more elements from Group II, III, IV, or VI of the Periodic Table. Use to prepare a substrate having such a layer.

33. The use according to any one of items 28 to 32, characterized in that at least one Si and / or Ge containing gas is used as the reactive gas and preferably further hydrogen gas is introduced into the reaction chamber. .

34. The process according to any one of 28 to 33, wherein the workpiece is at least 7.5 kV / (sccm · min), preferably at least 40 kPa / (sccm · min), more preferably at least 75 kPa / ( for use at a coating rate GR _F per unit of reactive gas plus units of sccm · min) or greater.

35. The substrate of clause 34, wherein the substrate is at a temperature of less than 600 ° C., preferably from 300 ° C. to 600 ° C. for Si, Ge, and compounds thereof, preferably from 300 ° C. to 800 ° C. for Ga compounds. Use for coating.

36. A vacuum vessel, comprising a cathode chamber connected to the vacuum vessel via an outlet and having at least one thermal cathode, a workpiece support disposed in the vessel, and an anode device, wherein the workpiece support is electrically insulated and assembled in the vessel. An installation for carrying out the method according to any one of claims 1 to 27.

37. The workpiece support of clause 36, wherein the workpiece support may be subjected to an adjustable voltage relative to the anode or the potential applied to the workpiece support is floating, in which case the container housing is at the anode potential and the cathode is at the anode potential. Relative to the cathode potential, preferably 10 to 80 V, particularly preferably 20 to 35 V, preferably the workpiece support can be adjusted to ± 25 V or less relative to the anode potential. Featured equipment.

38. The installation according to 36 or 37, wherein the anode device for discharging comprises a vacuum vessel wall or the anode device is assembled insulated in the container.

39. The work piece according to item 38, wherein the workpiece is arranged so that its potential is floating and its voltage is not set to more negative than -25 V for the anode device, preferably set from -3 V to -15 V. Equipment characterized in that.

40. The workpiece according to item 38, wherein the workpiece is preferably a voltage of -25 V to +25 V, preferably negative voltage, especially -15 V to -3, with respect to the anode device by means of adjustable bias sources. Equipment characterized in that it can be placed at a voltage of V.

41. The auxiliary anode according to any one of items 36 to 40, wherein the auxiliary anode is provided in the form of a ring anode arranged concentrically on the axis of the auxiliary anode, preferably the outlet. Equipment characterized in that it can be placed or so placed at the same or different potential.

42. The plant of any of paragraphs 36-41, wherein the vessel wall is floating in potential or fixed at a reference potential via an impedance element, preferably a resistance element.

43. The method according to any one of items 36 to 42, between at least a portion of the thermal cathode and the anode device.

10 V ≤ U _AK ≤ 80 V, preferably

20 V ≤ U _AK ≤ 35 V

The equipment characterized in that the voltage U _AK is set.

44. The method according to any one of items 36 to 43, between the maximum potential in the workpiece and the anode device.

-25 V ≤ U _s ≤ +25 V

The voltage of U _s , preferably the negative voltage, inter alia

-15 V ≤ U _s ≤ -3 V

And the voltage U _s is set.

45. The plant according to any one of items 36 to 44, characterized in that the gas supply line connected to the working gas tank, preferably the argon gas tank, is led to the cathode chamber.

46. The magnet device according to any one of items 35 to 45, wherein a magnet device is generated in the container which is coaxial with or substantially concentric with the outlet axis, wherein the magnet device is permanent. A facility comprising a magnet and / or one or more coil arrangements.

47. The plant according to any one of items 36 to 46, wherein the vessel is connected to a turbo vacuum pump, preferably a turbo molecular pump.

48. The plant of any of paragraphs 36-47, wherein the thermal cathode is supplied with an electron current of 5 to 400 A, preferably 20 to 100 A.

49. The workpiece according to any one of items 36 to 48, wherein the workpiece is disposed at the point with the highest electron density of the discharge in the vessel, and is preferably disposed in the vessel substantially concentrically with the outlet axis. Equipment.

50. The gas tank device according to any one of items 36 to 49, wherein the vessel is connected to a gas tank device containing Si and / or Ge containing gas or Ga containing gas, preferably further containing H _2. Equipment.

51. Use of a facility according to any of paragraphs 36 to 50 in accordance with any of paragraphs 28 to 35.

52. Use of a PECVD coating method by DC discharge to grow an epitaxial layer.

53. The method of any one of paragraphs 36 to 50, wherein the control of which of the polycrystalline layer, the amorphous layer, and the epitaxial layer is to be produced by pre-determining the properties of the workpiece surface, such as the crystal structure. Method of operating the plant according to the paragraph.

54. Use of the method according to any one of items 1 to 27 or the equipment according to any one of items 36 to 50 for producing a solar cell.

Summary

It is proposed to significantly increase the deposition rate by depositing a layer with a quality that meets epitaxy on the workpiece, for example by using a PECVD method under the application of a DC plasma discharge instead of UHV-CVD or ECR-CVD.

drawing

1

2

3

4

5

6

7

Claims (49)

The reactive gas or the reactive gas mixture introduced into the process chamber (PR) causes the ion energy E 0 eV <E ≤ 15 eV 1. A method of manufacturing a component as an electronic device, an optoelectronic device, an optical device, or a precision mechanical device, or as an intermediate material thereof, using at least one plasma accelerated processing step activated by a low energy plasma discharge (PL). A process for producing a component, characterized in that during the processing step the process atmosphere (PR) is isolated (15; 15a; 14; 15b) from the inner wall of the surrounding vacuum vessel (1). The process according to claim 1, wherein the at least one plasma promoting treatment step is at least one of the following: (a) coating of parts (b) alteration of the material composition of the part up to a given depth of penetration; (c) Etching the surface of the part. The process of claim 1 or 2, wherein the plasma accelerated cleaning step before and / or after the one or more plasma accelerated treatment steps is carried out as an additional plasma accelerated treatment step of this type, preferably hydrogen, inert gas, or mixtures thereof. A manufacturing method characterized by performing in a plasma containing. 4. The reactive according to any one of claims 1 to 3, wherein the component in which the precipitate has been locally deposited due to the one or more plasma promoting treatment steps, preferably containing hydrogen introduced into the process chamber (PR). Gas or reactive gas mixtures 0 eV <E ≤ 15 eV Cleaning using one or more partial cleaning steps activated by a low energy plasma discharge (PL) to ensure that the cleaning atmosphere is isolated from the inner wall of the vacuum vessel enclosed by the metal casing 15b during the partial cleaning step. Or, preferably, the cleaning atmosphere is directly bordered on the inner wall of the vacuum vessel (1) placed around it. The method according to claim 3 or 4, for manufacturing a virtual substrate, Iii) the substrate is cleaned according to claim 3 or 4, preferably using hydrogen together as a reactive gas; Ii) growing a hetero epitaxial layer as a plasma promoting treatment step; And iii) growing a semiconductor layer to be used as an additional plasma treatment step as necessary. The process according to any one of claims 1 to 5, wherein the components coming in the sequential time sequence in the process chamber PR are each treated with one or more plasma promoting treatment steps, and after performing a predetermined number of such plasma promoting treatment steps. An additional plasma accelerated treatment step consisting of a plasma accelerated process chamber cleaning step with no introduction of components or accompanying a substrate model is carried out in the process chamber PR, the process chamber cleaning step being an etching step and preferably hydrogen, an inert gas. Or a subsequent cleaning step in the plasma containing the mixture. The manufacturing method according to any one of claims 1 to 6, wherein the parts are processed in two or more plasma processing steps separated into place, and the parts transfer between the processing steps is performed in a vacuum. The process according to claim 7, wherein the transfer in vacuum is at least partially linear, preferably by linear feed movement into the process along the circular path, preferably by a moving component in the radial direction relative to the circular path. The manufacturing method characterized by the above-mentioned. The process according to any of the preceding claims, characterized in that the isolation is carried out by contacting the process chamber with a surface, preferably a dielectric surface or a graphite surface, which is inert to the plasma active reactive gas or gas mixture in the fresh state. Manufacturing method. 10. A method according to claim 9, wherein the surface of the isolation wall spaced from the inner wall of the vacuum vessel along most of the face sections is an inert surface. Method according to claim 10, characterized in that the process chamber (PR) and the intervening space (ZW) between the isolation wall and the inner wall of the vacuum vessel are equally or differently pumped (13a, 13b, 115). The method according to any one of claims 9 to 11, characterized in that a surface is made of one or more of the following materials in the state of a new one: Quartz, graphite, silicon carbide, silicon nitride, aluminum oxide, titanium oxide, tantalum oxide, niobium oxide, zirconium oxide, or a combination of such materials, diamond-like carbon or diamond. 13. The supply opening 123 for the component 120 is provided in the isolation wall, and the supply opening 123 is used for the component and / or the component 120 for processing. The manufacturing method characterized in that the closing by the support (119). 14. The plasma discharge according to any of claims 1 to 13, wherein the plasma discharge is implemented using an electron source 105 having an electron energy of ≤ 100 eV, preferably ≤ 50 eV, particularly preferably by DC discharge. The manufacturing method characterized by the above-mentioned. 15. The method according to claim 14, characterized in that the plasma discharge is implemented by a thermal ion cathode (107), preferably by a direct heating thermal ion cathode. The method according to any one of claims 1 to 15, wherein for plasma discharge two or more anodes which can be dropped on site and are preferably heated respectively, preferably anodes which can be operated separately respectively, are preferred. And a plasma density distribution (V) in the process chamber is set dynamically or statically by controlling the potential and / or the temperature applied to the anode, respectively, in the process chamber. The magnetic field (H) is generated in the process chamber (PR) (133, 135), and the plasma density distribution (V) on the surface of the component is statically generated by the magnetic field. Or dynamically set or controlled, preferably locally swept. 18. The process according to any one of the preceding claims, wherein the reactive gas is processed in an inflow direction, preferably approximately parallel to the part surface 120, and more preferably by injection points equidistantly spaced from the part surface. Distributing in an atmosphere (137), characterized in that the manufacturing method. Claim 1 to claim 18 according to any one of, wherein for at least one plasma promotes treatment step, the process chamber (PR) in the partial pressure of the work other than the inert gas and a reactive gas or gaseous reaction product gas 10 ^-8 mbar Or less, preferably maintained below 10 ⁻⁹ mbar (UHV). 20. The method of any one of claims 1 to 19, wherein the at least one plasma promoting step is to deposit a homo epitaxial layer or a hetero epitaxial layer. The method of claim 20, wherein the silicon / germanium layer is deposited as a homo epitaxial layer or a hetero epitaxial layer. 22. The manufacturing method according to any one of claims 1 to 21, wherein the part is a substantially disc-shaped part (120). 23. The manufacturing method according to any one of claims 1 to 22, wherein the component to be treated is a silicon wafer or a wafer made of a bonded semiconductor made of potassium arsenide, indium phosphide, silicon carbide, or glass, preferably glass. . 24. A process according to any one of the preceding claims, wherein the layer is deposited with one or more of the following materials: Silicon, silicon / germanium compound, silicon / germanium / carbon compound, diamond, diamond compound, silicon carbide, silicon nitride, aluminum oxide, silicon oxide, gallium nitride, gallium arsenide, aluminum, copper, indium phosphide, cubic boron nitride. The manufacturing method according to any one of claims 1 to 24, which is preferably used to manufacture a virtual substrate containing silicon / germanium. 26. The method according to any one of claims 1 to 25, wherein the surfaces of the surfaces to be treated at the same time are used for treating parts having a diameter of at least 150 mm, preferably at least 200 mm, more preferably at least 300 mm. Manufacturing method. 27. The manufacturing method according to any one of claims 1 to 26, wherein the plasma promoting treatment step coats the component at a coating rate of 60 nm / Min. A method of manufacturing a virtual substrate, preferably a silicon / germanium based virtual substrate or a component fabricated thereon, the method comprising: at least one cleaning step, The cleaning step is performed as a plasma accelerated cleaning step, during which the substrate to be cleaned is exposed to the reactive gas or gas mixture introduced into the process chamber, and the reactive gas or gas mixture is subjected to ion energy E at the surface of the part. 0 eV <E ≤ 15 eV A method of manufacturing a virtual substrate or a component based thereon, which is activated by a low energy plasma discharge. At least one vacuum chamber 1, At least one workpiece support 5 in the vacuum chamber, A plasma generating device for generating a plasma in the chamber 1, and A vacuum treatment system having a gas inlet device 7 connected to a gas tank device containing at least one reactive gas or gas mixture and introducing the reactive gas or gas mixture into the chamber 1, in particular claims 1 to 28. A vacuum processing system for carrying out the method according to claim 1, wherein The process chamber PR is provided in the vacuum chamber 1, the workpiece support 5 is exposed to the processing position in the process chamber PR, the plasma PL is generated in the process chamber PR, and the gas The inlet device is operatively associated with the process chamber PR, wherein the material 15, 15a, 113, preferably dielectric material or graphite, is inert to the plasma activated reactive gas or gas mixture with the process chamber inner wall surface fresh. Vacuum processing system, characterized in that further consisting of the material. 30. A vacuum processing system according to the preamble of claim 29, The process chamber PR is provided in the vacuum chamber, the workpiece support 5 is exposed to the processing position in the process chamber PR, the plasma PL is generated in the process chamber PR, and the gas inflow apparatus 7 ) Is operatively associated with the process chamber PR, wherein the process chamber PR is further formed by casings 14 and 15b spaced inward from the vacuum chamber wall along most of the face sections. system. A vacuum processing system incorporating the features of claim 29 or 30. 32. The vacuum treatment system according to any one of claims 29 to 31, wherein the inner surface of the process chamber consists of one or more of the following materials over at least a majority in the state of the new: Quartz, graphite, silicon carbide, silicon nitride, aluminum oxide, titanium oxide, tantalum oxide, niobium oxide, zirconium oxide, or a combination of such materials, diamond-like carbon or diamond. 33. The vacuum processing system according to any of claims 29 to 32, wherein the process chamber walls (14, 15b, 113) are interchangeably fixed with respect to the vacuum chamber walls (1). 34. The plasma generating apparatus according to any one of claims 29 to 33, wherein the plasma generating apparatus is a device for generating a low energy plasma discharge in which the ion energy E in the region of the workpiece support 5 is 0 eV < E &lt; 15 eV. Characterized by a vacuum processing system. 35. The plasma generator according to claim 34 comprises an electron source 105 having an electron energy of ≤ 100 eV, preferably ≤ 50 eV, preferably with a thermal cathode 107, in particular a direct heating cathode. And a DC low voltage plasma generator. 36. The vacuum chamber (1) according to any of claims 29 to 35, wherein the vacuum chamber (1) is preferably equipped with a cathode chamber (109) with electrical insulation therebetween, the cathode chamber (109) having a discharge port (111). A vacuum processing system, characterized in that the communication with the vacuum chamber (1) via. 37. The work piece according to claim 36, characterized in that the axis a of the discharge port 111 intersects with the workpiece receiving surface 119a of the workpiece support 19, preferably approximately perpendicularly from the center. Vacuum processing system. 38. The vacuum treatment system according to any one of claims 32 to 37, wherein the material of the process chamber wall 15b consists of a metal, preferably tantalum or inconel. . 39. The method according to any one of claims 35 to 38, wherein two or more anodes 117a and 117b spaced in place are provided in the process chamber PR, and the anodes 117a and 117b can be placed at different potentials. And preferably each can be heated. 38. The two or more anodes 17a, 117b, longitudinally misaligned along the outlet axis A, are provided coaxially with the axis, preferably in the process chamber, and the anode thereof. 117a, 117b can be placed at different potentials, preferably each can be heated. 41. The vacuum chamber wall (101) according to any one of claims 29 to 40, wherein the vacuum chamber wall (101) is formed as a double wall in most of the face sections, the intervening space being connected to a temperature control medium connection line, preferably for a temperature control liquid Vacuum processing system, characterized in that connected to the line. 42. The magnetic field generating device (133) according to any one of claims 29 to 41, comprising a Helmholtz coil (133) which generates a magnetic field in the process chamber (PR) and is preferably arranged outside the vacuum chamber. 135), preferably a controllable magnetic field generating device is provided. 43. The process chamber (PR) according to any of claims 29 to 42, wherein the process chamber (PR) is spaced apart from the vacuum chamber wall (1) along most of the face sections, and the interior of the process chamber (PR) and the intervening spaces formed thereby A vacuum processing system, characterized in that one or more pumping connection lines are operatively associated with a common pumping connection line via the same or different pumping cross sections, or at least one pumping connection line is provided for the process chamber and the intervening space, respectively. 44. The workpiece support 119 according to any one of claims 29 to 43 is driven linearly 121 with respect to the opening of the process chamber PR and in the normal direction of the opening face to be moved. And preferably closes the process chamber interior space at a position moved up towards the process chamber (PR). 45. The vacuum processing system according to any of claims 29 to 44, wherein the workpiece support (119) is operatively associated with the temperature control device (127). 46. The vacuum processing system according to any of claims 29 to 45, wherein the vacuum chamber (1) has one or more workpiece supply openings (129) which can be hermetically closed. 47. The vacuum chamber (1) according to any one of claims 29 to 46, wherein the vacuum chamber (1) has a workpiece supply opening (129) that can be controlled to be closed, the supply opening being via the vacuum workpiece transport device. And two or more vacuum chambers connected to each other. 48. The vacuum processing system according to claim 47, wherein the vacuum conveying device is a linear conveying device or a rotary conveying device (150), preferably the latter. 49. The plasma generating device and at least one reactive gas according to claim 47 or 48, wherein the process chamber PR provided in the vacuum chamber 1 is bound to the metal inner surface itself of the vacuum chamber 1, and generates plasma. And a gas inlet device connected to the tank device containing the vacuum.