Apparatus, system and method for plasma-enhanced chemical vapor deposition

Abstract

The present invention relates to an apparatus (1), a system (50), and a method (100) for plasma-enhanced chemical vapor deposition. A process chamber (2) is configured to receive at least one workpiece carrier (30). According to the present invention, the apparatus (1) is configured to heat the process chamber (2) using at least one workpiece carrier (30) that can be received by the process chamber (2).

Description

Technical Field

[0001] The present invention relates to an apparatus, a system, and a method for plasma-enhanced chemical vapor deposition.

Background Art

[0002] A method of chemical vapor deposition (CVD) for coating a substrate is known. At least one gas containing the substance to be deposited is supplied. The substance is deposited on the substrate, for example, by performing a chemical reaction that can be promoted by temperature. Using chemical vapor deposition, for example, microelectronic components or optical fibers can be manufactured.

[0003] The deposition rate can be further increased by generating plasma based on the gas. Furthermore, the deposition reaction has thus been made effectively promotable even at lower temperatures. This variation of chemical vapor deposition is usually referred to as plasma-enhanced chemical vapor deposition (PECVD).

[0004] To reach the required process temperature, a work carrier for transporting a substrate, for example, a semiconductor wafer, is usually inserted into a reaction chamber having a heatable wall. This reaction chamber is sometimes also referred to as a hot-wall reactor. Heating is usually performed by resistance heating elements installed on or within the process chamber wall.

Summary of the Invention

[0005] The object of the present invention is to further improve plasma-enhanced chemical vapor deposition, particularly to increase its efficiency.

[0006] This object is achieved by the apparatus, system, and method for plasma-enhanced chemical vapor deposition according to claims 1, 14, and 15.

[0007] An apparatus according to a first aspect of the present invention for plasma-enhanced chemical vapor deposition has a process chamber for receiving at least one work carrier. According to the present invention, the apparatus is configured to heat the process chamber to a process temperature for chemical vapor deposition, preferably using at least one work carrier that can be received by the process chamber.

[0008] Heating in the sense of the present invention is active heating in which at least one component is used specifically for heating. Heating here also includes temporary heating. During heating of a process chamber using at least one accepted work carrier, the work carrier consequently becomes capable of operating as, for example, a heating unit. In contrast, passive heating by, for example, waste heat is not heating in the sense of the present invention. Therefore, warming up of a process chamber resulting from heating of the electrodes of a work carrier as a result of plasma generation is not heating in the sense of the present invention.

[0009] One aspect of the present invention is based on an approach to designing an apparatus for plasma-enhanced chemical vapor deposition such that a process chamber for receiving at least one work carrier can be actively heated exclusively through at least one receptible work carrier. The apparatus may, in particular, be designed such that the process chamber can be heated using the work carrier independently of the process gas introduced into the process chamber and / or the vacuum generated within the process chamber.

[0010] In the sense of this invention, a vacuum is characterized by a pressure below atmospheric pressure acting on the apparatus. In other words, a vacuum in the sense of this invention refers to a negative pressure within the process chamber surrounding the apparatus, for example, a pressure substantially below 1 bar.

[0011] Therefore, the apparatus can be configured, for example, to operate the work carrier as a heating unit. Because the process chamber can be heated using the work carrier housed therein, a separate heating system for the apparatus, such as a heating element installed in the process chamber or heating cartridge area, can be omitted. Thus, the apparatus can be configured more simply and manufactured at a higher cost efficiency. Furthermore, the process chamber can be operated as a so-called "cold-wall reactor," thereby increasing operational safety. Moreover, by omitting a separate heating system, accidental heating of the process chamber when no work carrier is inserted can be avoided, or a corresponding complex safety mechanism that only allows heating when a work carrier is accepted can be omitted.

[0012] Furthermore, by using a device configured to heat the process chamber with a receptive work carrier, installation space within the process chamber can be saved, and therefore the process chamber can be made smaller. Consequently, the volume and mass to be heated can be reduced. This reduces the time required to reach the process temperature with the same heating power. Therefore, not only can the device operate with high energy efficiency, but workpiece processing can also be accelerated, and throughput can be increased accordingly.

[0013] The apparatus may optionally include a control unit configured to control the heating of a process chamber using at least one acceptable work carrier. The control unit may, in particular, be configured to cause at least one acceptable work carrier to act as a heating unit. The control unit may be configured, for example, to establish interconnections of the work carriers by current and / or voltage sources so that a heating current passes through at least a portion of the work carriers. For this purpose, the heating current may be a low-frequency alternating current, e.g., an alternating current with a frequency of less than 1 kHz, preferably about 50 Hz. A portion of the work carrier, e.g., a plurality of electrodes connected in series, can be used here as a heating resistor.

[0014] Preferred embodiments of the present invention and their improvements are described below. Each of them may be optionally combined with others and in the embodiments of the present invention described later, unless expressly excluded.

[0015] In a preferred embodiment, the apparatus includes a switching unit configured to selectively connect at least one work carrier received by a process chamber to at least one heating voltage source or plasma voltage source. The heating voltage source is appropriately configured to supply a low-frequency AC voltage for heating the process chamber, and the plasma voltage source is appropriately configured to supply a high-frequency AC voltage to generate plasma. In this case, the low-frequency AC voltage has a frequency of 1 kHz or less, for example, 50 Hz, and the high-frequency AC voltage has a frequency of 1 kHz or more, for example, 40 kHz. The switching unit is preferably configured to selectively integrate the work carrier received by the process chamber into a plasma circuit for supplying a high-frequency AC current or into at least one heating circuit for supplying a low-frequency AC current. In particular, the switching unit may be configured to selectively integrate the work carrier received by the process chamber for operation as a plasma unit into a single plasma circuit for supplying a high-frequency AC current in at least two, preferably parallel heating circuits, for supplying a low-frequency AC current and for operation as a heating unit. Therefore, various operating modes of at least one accepted work carrier can be implemented using the switching unit.

[0016] The heating voltage source is configured to supply a low-frequency AC voltage with an effective voltage of, for example, 145V and an effective amperage higher than 90A, for example, 120A. The plasma voltage source is configured to supply a high-frequency AC voltage with an effective voltage of, for example, 800V to 1000V and an effective amperage lower than 90A, for example, 75A.

[0017] In a more preferred embodiment, the switching unit has at least two switch assemblies configured to interrupt the conductive connections of at least one heating voltage source and a plasma voltage source to a power supply connection to which a work carrier can be connected. The switch assemblies are configured, in particular, to interrupt the electrical lines from at least one heating voltage source or plasma voltage source to the contact pins of the power supply connection, and are sometimes referred to as current lances. Each of the switch assemblies may have at least one switch integrated into one of the lines. Thus, at least one heating voltage source and a plasma voltage source can be connected independently of each other to at least one receptive work carrier.

[0018] A control unit for controlling the heating of a process chamber using at least one receptive work carrier is preferably part of a switching unit. The control unit is appropriately configured to control at least two switch assemblies. The control unit can be configured, for example, to open and close switch assemblies. In particular, the control unit may be configured to disconnect the heating voltage source from the work carrier and connect the plasma voltage source to the work carrier by appropriate operation of the switch assemblies in response to the presence of a switching signal. The switching signal may be, for example, a switching signal generated by the user and supplied via a user interface. Alternatively or additionally, the switching signal may be generated by the control unit, for example, when the temperature of the work carrier or its surroundings reaches or exceeds the process temperature. For this purpose, the control unit may be connected to a temperature sensor configured to identify or at least estimate the work carrier temperature or ambient temperature.

[0019] In a more preferred embodiment, the apparatus has a power connection section to which a work carrier receivable in the process chamber can be connected. The power connection section preferably includes at least four contact pins for electrically contacting the work carrier receivable in the process chamber. Thus, at least two circuits of the work carrier can be supplied with current and / or voltage independently of each other.

[0020] The contact pin may, for example, protrude from the wall of the process chamber, and may be positioned so that when the work carrier is received by the process chamber, the contact pin contacts a contact provided for electrical connection on the work carrier. In particular, the contact pin may be designed to engage with a corresponding, preferably conical, borehole on the work carrier. Thus, as the work carrier is inserted into the process chamber, the contact pin slides into the borehole, and the contact pin can be guided to a given position. Thus, particularly reliable electrical connection of the work carrier to the apparatus can be achieved. To ensure a minimum contact pressure on the contact pin when at least one work carrier is received into the process chamber, the contact pin may be spring-loaded within the process chamber.

[0021] In a more preferred embodiment, the contact pin is located in the area of ​​the rear wall of the process chamber. The rear wall should be understood here as the wall of the process chamber opposite to the at least one opening for inserting the work carrier into the process chamber. The contact pin is preferably positioned so that it automatically contacts the at least one work carrier when the at least one work carrier is received into the process chamber. The contact pin may be positioned, for example, so that it contacts the corresponding contact of the work carrier at the end of the insertion of the at least one work carrier into the process chamber. Thus, the operation of the apparatus can be facilitated. On the other hand, an additional contact step that would require the at least one work carrier receivable into the process chamber to be actively interconnected with the apparatus can be omitted. On the other hand, the correct interconnection of the work carriers does not have to be explicitly ensured. Rather, this can be achieved solely by the complete insertion of the work carriers into the process chamber.

[0022] In a more preferred embodiment, the process chamber is configured to accommodate two work carriers adjacent to each other. The process chamber is appropriately formed to be sufficiently wide for this purpose, i.e., at least twice as wide as a single work carrier. Accordingly, the process chamber may also have two power connections for separately connecting each work carrier. The dimensions of the process chamber for accommodating two work carriers can increase throughput.

[0023] In a more preferred embodiment, the process chamber has two closable openings arranged adjacent to each other for inserting at least one work carrier into the process chamber. The two openings are preferably separated from each other by a retaining web, where a door or flap for closing the openings can be retained. Thus, the two work carriers can be inserted into or removed from the process chamber independently of each other.

[0024] In a more preferred embodiment, the process chamber is substantially rectangular and configured to accommodate at least one work carrier having a substantially rectangular cross-section. Thus, the volume of the process chamber is optimally suited to the profile of the work carrier. In particular, the dead volume of the process chamber can be minimized. This allows for the optimal design of the gas exhaust system, especially the vacuum pump, for generating a vacuum within the process chamber, and reduces the consumption of process gas supplied into the process chamber.

[0025] In a further preferred embodiment, the process chamber has at least one reflecting unit configured to reflect electromagnetic irradiation emitted by at least one receptive workpiece carrier, particularly thermal irradiation in the infrared region of the electromagnetic spectrum, towards the workpiece carrier. The at least one reflecting unit can have, for example, for this purpose, a plurality of preferably rectangular plates. The at least one reflecting unit enables a more efficient operation of the device. In particular, since the period until the process chamber reaches a predetermined process temperature can be shortened using at least one reflecting unit, the throughput can be increased. Thus, energy can also be saved simultaneously.

[0026] A plurality of plates appropriately form a laminate, and electromagnetic irradiation is reflected particularly effectively using it. The plates can here be manufactured from various materials each particularly suitable for reflecting a specific wavelength. By stacking such plates to form the reflecting unit, electromagnetic irradiation can also be effectively reflected over a wide wavelength range.

[0027] In a further preferred embodiment, the process chamber has at least three reflecting units, which are arranged at substantially right angles to each other such that, with the workpiece carrier received in the process chamber, the reflecting units are positioned above the workpiece carrier and along two opposing longitudinal sides. Thus, at least most of the electromagnetic irradiation emitted by at least one receptive workpiece carrier can be reflected. Thus, in particular, a larger angular range around at least one receptive workpiece carrier is covered using the reflecting units. The above configuration of the reflecting units enables not only an increase in energy efficiency and an acceleration of the heating process but also a reliable limitation of the wall temperature of the process chamber.

[0028] In a further preferred embodiment, the device has a gas supply system for supplying process gas to the process chamber.

[0029] The gas supply system preferably includes a plurality of injectors. The injectors are appropriately arranged in the area of the ceiling of the process chamber so as to supply the process gas onto the work carrier when the work carrier is received, whereby the process gas can be appropriately supplied from above. For this purpose, the injector can be installed, for example, on the ceiling of the process chamber. By providing a plurality of injectors that fluidly connect the process chamber to, for example, at least one row of gas supply lines, a particularly uniform distribution of the process gas supplied to the process chamber becomes possible. Therefore, the work carried by the work carrier can also be processed particularly uniformly.

[0030] The plurality of injectors are preferably, here for example, dispersed along the ceiling of the process chamber in the form of an injector array. The plurality of injectors can be arranged particularly along the insertion direction in which at least one work carrier can be inserted into the process chamber. In particular, rows of injectors arranged front and back in the insertion direction can be provided for each work carrier that can be received in the process chamber. In order to enable the introduction of two different process gases, two parallel rows of such injectors arranged front and back can also be considered in some cases. Each row of injectors is fluidly connected here to one of the two rows of process gas supply lines as appropriate, and / or is arranged adjacent to each other series of injectors in order to enable a uniform dispersion of the two different process gases.

[0031] The injector is preferably designed in a nozzle shape for the directed injection of the process gas. In the area of the opening of the discharge port discharging into the process chamber, each of the injectors can be shaped, for example, such that the process gas can be sprayed into the process chamber substantially linearly in the form of a jet, that is, with only slight diffusion. Therefore, the process gas can be supplied, in particular, to the area where at least one component of the process gas is deposited on the surface of the work carried by the work carrier, for example, between the electrodes of at least one received work carrier. On the other hand, the supplied process gas can be used particularly efficiently as a result, and accordingly, the consumption of the process gas can be reduced.

[0032] In a more preferred embodiment, a nozzle-shaped injector is positioned to blow a process gas between a plurality of parallel electrodes of at least one receptive work carrier. This facilitates the generation of plasma between the electrodes, or enables plasma generation with a small amount of supply gas. Thus, the supply gas can pass particularly between the electrodes of the work carrier and be drawn out at the bottom of at least one receptive work carrier, without being pre-dispersed (unnecessarily) within the process chamber.

[0033] In a more preferred embodiment, the apparatus includes a gas discharge system.

[0034] The gas exhaust system preferably comprises a plurality of gas outlets located in the bottom region of the process chamber to draw gas from beneath the work carrier once the work carrier is received. The gas outlets may be formed, for example, as openings in the bottom of the process chamber. The plurality of gas outlets are preferably dispersed along the bottom of the process chamber, for example, in the form of a gas outlet array. The plurality of gas outlets may be arranged particularly along the insertion direction. One gas outlet is preferably provided here for each injector, particularly for each pair of injectors with two parallel rows of injectors. Thus, the process gas can be drawn homogeneously from the process chamber. This is advantageous, especially in the case of homogeneous gas supply via multiple injectors, as it avoids undesirable concentration differences.

[0035] A system according to a second embodiment of the present invention for plasma-enhanced chemical vapor deposition comprises an apparatus according to a first embodiment of the present invention for plasma-enhanced chemical vapor deposition, and a work carrier, by which the process chamber of the apparatus can be heated. The work carrier is preferably designed to be insertable into the process chamber of the apparatus, and more particularly to be receivable in the process chamber. The work carrier is appropriately designed to be operated by the apparatus as a heating unit. For this purpose, the heating unit may have, for example, a plurality of heating circuits formed by electrodes of the work carrier. The electrodes are preferably used here as heating resistors to which a low-frequency AC voltage can be applied. In a particularly preferred embodiment, the work carrier is also designed to be operated by the apparatus here as a plasma unit, by which plasma can be generated in the process chamber. For this purpose, for example, at least two of the heating circuits may have electrodes that are isolated from each other and adjacent to each other, so that a high-frequency AC voltage can be applied between adjacent electrodes.

[0036] In a third aspect of the present invention for plasma-enhanced chemical vapor deposition, the process chamber is heated by the present invention using at least one workpiece or workpiece carrier that can be accepted into the process chamber. In other words, the process chamber can be actively heated by the workpiece or workpiece carrier.

[0037] A heating current in the form of a low-frequency alternating current is appropriately supplied to the workpiece or workpiece carrier, and in this respect, for example, a corresponding AC voltage is applied to the workpiece or workpiece carrier. For example, the AC voltage can be applied to an electrode assembly, particularly to multiple electrodes of an electrically series-connected electrode assembly, at a frequency of less than 1 kHz, for example, 50 Hz. The electrodes are used here as heating resistances as appropriate. Alternatively, the workpiece may be used as a heating resistance. With the method according to the present invention, a conventional heating system located within the region of the process chamber does not need to be used to heat the process chamber. For example, a separate heating unit can be omitted, and as a result, an apparatus with a smaller process chamber can be used. This also makes it possible to shorten the time required to reach the process temperature to be given for vapor phase deposition. At the same time, the complexity of the method can be reduced by using the method according to the present invention. Higher deposition rates may also be possible in the case of individual applications.

[0038] Before heating the process chamber, the work carrier or workpiece may be inserted into the process chamber, for example, via rollers positioned within the process chamber. The work carrier is interconnected to the device's switching unit, particularly automatically, and preferably electrically. For example, the work carrier may be inserted into the process chamber until contacts on the work carrier contact contact pins of the device's power connection unit located in the rear wall region of the process chamber.

[0039] The workpiece or workpiece carrier is operated as appropriate after heating as a plasma unit. For this purpose, a high-frequency AC voltage with a frequency of 1 kHz or higher, for example 40 kHz, can be applied to the workpiece or workpiece carrier, especially the electrodes. Thus, the workpiece or workpiece carrier can be used particularly efficiently.

[0040] The present invention will be described in more detail below with reference to the drawings. Where appropriate, elements that function identically are given the same reference numerals. The present invention is not limited to the exemplary embodiments shown in the drawings, even in terms of functional features. The foregoing description and the following description of the drawings include a number of features that may be combined as a composite in dependent claims. These features, including all other features disclosed above and in the following description of the drawings, can also be considered individually by those skilled in the art and combined to form reasonable further combinations. In particular, each of all the above features can be combined individually and in any suitable combination with the apparatus according to the first aspect of the present invention, the system according to the second aspect of the present invention, and the method according to the third aspect of the present invention.

[0041] In the drawings, they are at least partially schematic. [Brief explanation of the drawing]

[0042] [Figure 1] Figure 1 shows a side view of an example of a apparatus for plasma-enhanced vapor deposition. [Figure 2] Figure 2 shows an example of a system for plasma-enhanced vapor deposition. [Figure 3] Figure 3 shows an example of a system for plasma-enhanced vapor deposition. [Figure 4] Figure 4 shows an example of a method for plasma-enhanced vapor deposition. [Modes for carrying out the invention]

[0043] Figure 1 shows a side view of an example apparatus 1 for plasma-enhanced vapor deposition. Apparatus 1 comprises a process chamber 2 for receiving at least one work carrier through a closable opening 17, a gas supply system 3 for supplying at least one process gas to the process chamber 2, and a gas exhaust system 4 for creating a vacuum within the process chamber 2. Apparatus 1 is configured to heat the process chamber 2 using at least one work carrier received in the process chamber 2.

[0044] For this purpose, the apparatus 1 includes a power connection unit 5 for electrically connecting the work carrier to the apparatus 1. The power connection unit 5 is preferably located inside the process chamber 2, particularly in the area of ​​the rear wall 6 of the process chamber 2. The power connection unit 5 preferably has a plurality of contact pins 7, which may also be called a power lance. The contact pins 7 are preferably arranged so that the work carrier inserted into the process chamber 2 contacts the contact pins 7 on the rear wall 6.

[0045] The power connection unit 5 is preferably part of the switching unit (see Figure 3) of the apparatus 1, and the switching unit is configured to integrate, via the power connection unit 5, at least one work carrier receivable in the process chamber 2 for heating the process chamber 2 into at least one heating circuit for supplying a low-frequency alternating current. Furthermore, the switching unit may also be configured to integrate, via the power connection unit 5, the receivable work carrier into a plasma circuit for supplying a high-frequency alternating current to generate plasma in the process chamber 2.

[0046] The roller 8 is preferably positioned within the process chamber 2 to insert at least one work carrier into the process chamber 2. The roller 8 may have, for example, a concave running surface (see Figure 2) on which the running rails of the work carrier are guided. Here, the roller 8 is positioned along the insertion direction E, which allows at least one work carrier to be inserted into the process chamber 2. In addition to the easy insertion of at least one work carrier into the process chamber 2, the roller 8 also enables precise alignment of the work carrier within the process chamber 2. Thus, it can be ensured that the contact pin 7 reliably contacts a predetermined contact on the end of the work carrier that is receivable in the process chamber 2, the end facing the power connection 5. For reasons of clarification, only one of the rollers 8 is referenced.

[0047] After at least one work carrier is inserted into the process chamber 2 by rollers 8 and the opening 17 of the process chamber 2 is sealed, for example, with a door or flap (see Figure 2), the gas inside the process chamber 2 becomes available for extraction by a gas extraction system 4. The gas extraction system 4 optionally includes at least one vacuum pump 9 for this purpose, which is connected to the process chamber 2, for example, via a gas exhaust line 10. The gas extraction system 4 preferably further includes a plurality of gas outlets 11, which begin at the bottom 12 of the process chamber 2 and exit into the gas exhaust line 10. The number of gas outlets 11 ensures that the gas inside the process chamber 2 is extracted uniformly. Uniform extraction can be further improved by distributing the gas outlets 11 continuously across the bottom 12 of the process chamber 2, parallel to the insertion direction E, as shown, for example, in Figure 1. For reasons of clarity, only one of the gas outlets 11 is referenced.

[0048] Once the process chamber 2 is heated to a process temperature for gas phase deposition using at least one work carrier receivable by the process chamber 2, at least one gas can be introduced into the process chamber 2 using a gas supply system 3. For this purpose, the gas supply system 3, in the illustrated example, has two gas supply lines 13, each of which can be connected to a process gas source, such as a process gas tank or a process gas source line. The gas supply system 3 preferably further has a plurality of injectors 14, which can inject the process gas guided by the gas supply lines 13 into the process chamber 2. Injectors 14, appropriately positioned inside the process chamber 2, particularly in the area of ​​the ceiling 15 of the process chamber 2, can here be connected to the gas supply lines 13 via, for example, an injector supply line 16. For reasons of clarity, only one of the injectors 14 and only one of the injector supply lines 16 are reference numerals.

[0049] The multiple injectors 14 are preferably designed in a nozzle shape and arranged so that the process gas guided by the two gas supply lines 13 can be blown into the process chamber 2 in a directional manner, particularly in the direction of the work carrier received by the process chamber 2. The injectors 14 may be arranged in the insertion direction E, similar to the gas outlet 11. All the injectors 14 assigned to one gas supply line 13 and consequently one process gas preferably form a row, as in this case.

[0050] As shown in the illustrated example, when the injector 14 on the ceiling 15 of the process chamber 2 and the opening of the gas outlet 11 on the bottom 12 of the process chamber 2 face each other, this can greatly promote the maintenance of a homogeneous concentration of the process gas introduced into the process chamber 2. Therefore, the resulting homogeneous processing conditions can ensure that the workpieces being processed simultaneously have uniform characteristics.

[0051] To enable optimal use of the heat generated in response to the heating of the process chamber, the apparatus 1 preferably has at least one reflective unit 20 for reflecting electromagnetic irradiation, particularly thermal irradiation from the infrared region of the electromagnetic spectrum. The at least one reflective unit 20 is preferably composed of laminated plates. The multiple plates of the laminate may here be manufactured from different materials for reflecting irradiation having different wavelengths, for example, to enable efficient reflection of thermal irradiation over a wide wavelength range.

[0052] In the illustrated example, one reflective unit 20 is positioned on the ceiling 15 of the process chamber 2, particularly parallel to the ceiling 15, so that electromagnetic radiation radiated from the workpiece carrier received in the process chamber 2 toward the ceiling 15 is reflected back to the workpiece carrier. Therefore, the process chamber 2 can be heated more quickly.

[0053] To avoid obstructing the supply of process gas to the process chamber 2, the reflecting unit 20 preferably has a borehole in the form of a passage through which the injector 14 passes. In contrast to the example shown herein, the injector 14 may also terminate flush with the reflecting unit 20.

[0054] Figure 2 shows a system 50 for plasma-enhanced vapor deposition. The system 50 comprises an apparatus 1 for plasma-enhanced vapor deposition having a process chamber 2 capable of receiving at least one work carrier 30, and at least one work carrier 30. Apparatus 1 is shown in a front view in Figure 1 and is configured to heat the process chamber 2 using at least one received work carrier 30.

[0055] The apparatus 1 shown herein is designed similarly to the apparatus 1 shown in Figure 1. However, the gas exhaust system is omitted for clarity. Components or assemblies hidden by other components or assemblies are shown in this case with dashed lines.

[0056] In this example, the process chamber 2 is configured to receive two adjacent work carriers 30, i.e., two work carriers 30 arranged transversely in the insertion direction (see Figure 1). The process chamber 2 has two adjacent openings 17 as appropriate, which can be closed using doors 18 for the insertion of the work carriers 30. In the illustrated example, only the left door 18 is shown in Figure 2, and therefore hides one of the openings 17. The right door 18 in Figure 2 is shown as transparent.

[0057] The two openings 17 are preferably separated from each other by a retaining web 19 for a door 18. The process chamber 2 extends behind the retaining web 19, but also extends appropriately behind both openings 17. That is, there is no gas separation between the two regions in which the work carrier 30 is received by the process chamber 2.

[0058] Apparatus 1 is preferably provided with rollers 8 located within the process chamber 2 to facilitate the insertion of the work carrier 30. The work carrier 30 preferably has corresponding running rails 33 that can be guided by the concave running surface of the rollers 8. Alternatively, other guide systems for guiding the work carrier 30 within the process chamber 2 are also possible. For example, the work carrier 30 may be provided with rollers that can roll on the running rails within the process chamber 2. In other modifications, in relation to modifications having rollers, sliding elements may be provided to save installation space.

[0059] As is very clear in Figure 2, the process chamber 2 is preferably rectangular. Therefore, a rectangular work carrier 30 can be efficiently accommodated, that is, unused space, also known as dead volume, within the process chamber 2 can be avoided or at least reduced. This also promotes the creation of a vacuum in the process chamber 2 and reduces the consumption of process gas.

[0060] The two gas supply lines 13 of the gas supply system 3 extend over the upper part of the process chamber 2 in the illustrated example. The injector supply lines 16 are appropriately started from each gas supply line 13 on two opposing sides, preferably in pairs. This allows for a particularly uniform supply of process gas to each of the two work carriers 30 received by the process chamber 2. The injectors 14 connected to the injector supply lines 16 are preferably located in the area of ​​the ceiling 15 of the process chamber 2 such that two injectors 14 are adjacent to each other for injecting different process gases into one of the received work carriers 30. As a result, for example, trimethylamine (TMA) may be supplied by at least one injector 14, and monosilane (SiH4), ammonia (NH3), nitrous oxide (N2O), or methane (CH4) may be supplied by at least one other injector 14.

[0061] Alternatively, to enable the simultaneous supply of other process gases, three or more gas supply lines 13 are conceivable, each having a corresponding injector supply line to another injector. At least one compound from the group consisting of monophosphine (PH3), diborane (B2H6), and oxygen (O2) can be advantageously supplied as such other process gases.

[0062] Four reflective units 20 arranged in the process chamber 2 are also shown in Figure 2. Two of these reflective units 20 are positioned in the area of ​​the ceiling 15 of the process chamber 2, particularly above the work carrier 30, relative to the received work carrier 30. The other two reflective units 20 are positioned in the area of ​​the side walls 21 of the process chamber 2, particularly along the lateral sides of the work carrier 30, relative to the received work carrier 30. Thus, in response to the heating of the process chamber 2, the electromagnetic irradiation emitted by the work carrier 30 can be reflected back to the work carrier 30.

[0063] The same effect can be achieved even if only one reflective unit 20 extending substantially across the entire width of the process chamber 2 is provided instead of the two reflective units 20 in the area of ​​the ceiling 15. Thus, embodiments having at least three reflective units 20 are also advantageous.

[0064] Figure 3 shows an example of a switching unit 22. Preferably, the switching unit 22 is configured to operate a work carrier 30, which can be accepted into the process chamber of a plasma-enhanced vapor deposition apparatus, in a first operating mode as a heating unit for heating the process chamber, and in a second operating mode as a plasma unit for generating plasma from at least one process gas supplied into the process chamber.

[0065] For this purpose, the switching unit 22 appropriately comprises a plurality of switch assemblies 23a, 23b, a plasma voltage source 24 for supplying a high-frequency AC voltage to generate plasma, and at least one heating voltage source 25 for supplying a low-frequency AC voltage to heat the process chamber.

[0066] The switching unit 22 is preferably designed so that the work carrier 30 makes electrical contact in response to the acceptance of the work carrier 30 by the process chamber. Therefore, the switching unit 22 can selectively establish an electrical connection between the plasma voltage source 24 or at least one heating voltage source 25 and the work carrier 30. For this purpose, the switching unit 22 may have, for example, a power connection section having a plurality of contact pins 7 located within the process chamber. The contact pins 7 allow, for example, corresponding contacts 31 on the work carrier 30 to be made contact. For reasons of clarity, only one of the contacts 31 and only one of the contact pins 7 are referenced.

[0067] The switching unit 22 is preferably configured to first electrically connect at least one heating voltage source 25 to a work carrier 30 that can be accepted into the process chamber, for example, by closing a first switch assembly 23a. The switching unit 22 may be configured to integrate the work carrier 30 into at least one heating circuit by establishing this electrical connection.

[0068] The switching unit 22 may be designed such that, for example, upon closing the first switch assembly 23a, (i) a low-frequency alternating current flows between two poles 25a, 25b of at least one heating voltage source 25 through a first group of electrodes 32a of the electrode assembly of the work carrier 30 receivable in the process chamber, and (ii) a low-frequency alternating current flows between two other poles 25c, 25d of at least one heating voltage source 25 through a second group of electrodes 32b of the electrode assembly. As can be seen from Figure 3, each of the electrodes 32a, 32b of one group is electrically connected in series. In this case, four heating circuits are implemented by providing two poles 54a and 54c using the interconnection shown in the example.

[0069] When the first switch assembly 23a is closed, electrodes 32a and 32b can act as heating resistors, and therefore the work carrier 30 can operate as a heating unit in the first operating mode.

[0070] The switching unit 22 is preferably further configured to disconnect the heating voltage source 25 from the work carrier 30 that can be accepted into the process chamber, for example, by opening the first switch assembly 23a and closing the second switch assembly 23b, and instead electrically connect the plasma voltage source 24 to the work carrier 30. The switching unit 22 may be configured in particular to integrate the work carrier 30 into the plasma circuit by establishing this electrical connection.

[0071] The switching unit 22 may be designed such that, for example, in response to the closing of the second switch assembly 23b, a high-frequency AC voltage is applied between the first group of electrodes 32a and the second group of electrodes 32b. For this purpose, the switching unit 22 may be designed such that, in particular, in response to the closing of the second switch assembly 23b, the first pole 24a of the plasma voltage source 24 becomes connectable to the first group of electrodes 32a and the second pole 24b becomes connectable to the second group of electrodes 32b.

[0072] The electrodes 32a of the first group and electrodes 32b of the second group are preferably arranged alternately as shown in Figure 3, and when the second switch assembly 23b is closed, a high-frequency electric field is generated as a result, which can generate plasma, so that the work carrier 30 can operate as a plasma unit in the second operating mode.

[0073] The corresponding control of switch assemblies 23a and 23b can be performed by a control unit. However, the control unit is not shown in Figure 3 for the sake of clarity.

[0074] Figure 4 shows an example of a method 100 for plasma-enhanced chemical vapor deposition.

[0075] Preferably, in step S1 of the method, at least one work carrier is inserted into the process chamber of the apparatus for plasma-enhanced chemical vapor deposition. For this purpose, the work carrier may be inserted, for example, through an opening in the process chamber by a guide system, such as rollers positioned inside the process chamber. The work carrier is simultaneously electrically interconnected with the apparatus's switching unit in a manner suitable for the process. For example, the work carrier may be inserted into the process chamber until contacts on the work carrier contact contact pins of the apparatus's power supply connection located in the rear wall region of the process chamber.

[0076] When at least one work carrier is received by the process chamber in a further method step S2, i.e., fully inserted, a vacuum is preferably generated within the process chamber. The gas inside the process chamber can be drawn out here using a gas exhaust system, in particular through multiple gas outlets within the process chamber. By providing multiple gas outlets, and in particular by distributing the gas outlets across the bottom of the process chamber, particularly efficient vacuum evacuation of the process chamber is possible.

[0077] In a further step S3, the process chamber is heated using at least one accepted work carrier. For this purpose, the work carrier may be integrated by a switching unit into at least one heating circuit for energizing a low-frequency alternating current. The work carrier is preferably connected here to at least one heating voltage source to supply a low-frequency AC voltage. Thus, the low-frequency alternating current may be energized through at least a portion of the work carrier, for example, through a plurality of electrodes connected in series, so that the work carrier is at least partially heated.

[0078] If the temperature inside the process chamber, particularly the temperature of the work carrier, reaches or exceeds a predetermined process temperature, in a further method step S4, at least one process gas, such as SiH4, a silane such as trimethylsilane, and / or nitrous oxide gas N2O, may be supplied into the process chamber. The at least one process gas may be blown into the process chamber in a homogeneous dispersion, particularly through a plurality of injectors, preferably located in the ceiling region of the process chamber.

[0079] In a further step S5, at least one heating voltage source is preferably disconnected from at least one accepted work carrier. Alternatively, the work carrier may be integrated by a switching unit into a plasma circuit for conducting a high-frequency alternating current. The work carrier is preferably, in this case, connected to a plasma voltage source to supply a high-frequency AC voltage. Thus, two different potentials can be applied to two components or groups of components, particularly two different groups of electrodes, thereby forming a high-frequency alternating electric field between the electrodes and generating plasma from at least one supply process gas.

[0080] The above-described order of method steps S2 to S5 is not required here. Rather, as shown in Figure 4, method steps S2 and S3 are performed at least temporarily simultaneously. Method steps S4 and S5 may also be performed simultaneously. Method step S2 is preferably performed until the desired deposition is achieved on the workpieces transported by the work carrier, i.e., the generated vacuum is maintained. [Explanation of Symbols]

[0081] 1 device 2 process chambers 3. Gas supply system 4. Gas Emission System 5. Power connection section 6 Rear wall 7 Contact pins 8 Laura 9. Vacuum pump 10 Gas exhaust line 11 Gas outlet 12 Bottom 13 Gas supply lines 14 Injector 15 Ceiling 16. Injector supply line 17 Opening 18 doors 19 Stop the Web 20 Reflective Units 21 Side wall 22 Switching Unit 23a, 23b Switch Assembly 24 Plasma voltage source 24a, 24b Pole 25 Heating voltage source 25a~d Pole 30 Work Career 31 Contacts 32a, 32b electrode 50 Systems 100 ways S1-S5 Method Steps

Claims

1. An apparatus (1) for plasma-enhanced chemical vapor deposition having a process chamber (2) for receiving at least one workpiece carrier (30), configured to heat the process chamber (2) using at least one workpiece carrier (30) receivable in the process chamber (2); a switching unit (22) configured to selectively connect the at least one acceptable workpiece carrier (30) to at least one heating voltage source (25) or plasma voltage source (24); The switching unit (22) selectively integrating said at least one acceptable workpiece carrier (30) into a single plasma circuit energized with high frequency alternating current via a power connection (5) so as to operate as a plasma unit; selectively integrating said at least one acceptable workpiece carrier (30) with at least two heating circuits carrying low-frequency alternating current via said power supply connections (5) so as to operate as a heating unit; Device (1).

2. 2. The apparatus (1) according to claim 1, wherein the switching unit (22) comprises at least two switch assemblies (23a, 23b) configured to interrupt the conductive connection of the at least one heating voltage source (25) and the plasma voltage source (24) to the power supply connection (5) to which a workpiece carrier (30) can be connected.

3. The switching unit (22) comprises the power supply connection part (5) to which the at least one acceptable work carrier (30) can be electrically connected; 3. The device (1) according to claim 1 or 2, wherein the power connection (5) has at least four contact pins (7) for making electrical contact with the at least one receptive workpiece carrier (30).

4. 4. The device (1) according to claim 3, wherein the contact pins (7) are arranged in the region of the rear wall (6) of the process chamber (2).

5. 5. The apparatus (1) according to any one of claims 1 to 4, wherein the process chamber (2) is configured to receive two workpiece carriers (30).

6. An apparatus (1) for plasma-enhanced chemical vapor deposition having a process chamber (2) for receiving at least one workpiece carrier (30), comprising: configured to heat the process chamber (2) using at least one workpiece carrier (30) receivable in the process chamber (2); The process chamber (2) has two closable openings (17) arranged adjacent to each other for inserting the at least one workpiece carrier (30) into the process chamber (2).

7. An apparatus (1) for plasma-enhanced chemical vapor deposition having a process chamber (2) for receiving at least one workpiece carrier (30), comprising: configured to heat the process chamber (2) using at least one workpiece carrier (30) receivable in the process chamber (2); The process chamber (2) has at least one reflecting unit (20) configured to reflect electromagnetic radiation emitted from at least one receptive work carrier (30) towards the work carrier (30).

8. 8. The apparatus (1) according to claim 7, wherein the process chamber (2) has three reflective units (20), which are arranged at approximately right angles to each other so that when a work carrier (30) is received in the process chamber (2), the three reflective units (20) are positioned above the work carrier (30) and along two opposing longitudinal sides.

9. An apparatus (1) for plasma-enhanced chemical vapor deposition having a process chamber (2) for receiving at least one workpiece carrier (30), comprising: configured to heat the process chamber (2) using at least one workpiece carrier (30) receivable in the process chamber (2); The apparatus (1) comprises a gas supply system (3) for supplying a process gas to the process chamber (2), the gas supply system (3) having a plurality of injectors (14) arranged in the area of ​​a ceiling (15) of the process chamber (2) so as to supply the process gas to the upper part of the work carrier (30) relative to the received work carrier (30).

10. 10. The apparatus (1) according to any one of claims 1 to 9, comprising a gas supply system (3) for supplying process gas into the process chamber, the gas supply system (3) having a plurality of injectors (14) designed as nozzles for directional injection of process gas.

11. An apparatus (1) for plasma-enhanced chemical vapor deposition having a process chamber (2) for receiving at least one workpiece carrier (30), comprising: configured to heat the process chamber (2) using at least one workpiece carrier (30) receivable in the process chamber (2); a gas supply system (3) for supplying process gas into the process chamber, the gas supply system (3) having a plurality of injectors (14) designed as nozzles for directional injection of the process gas; The injector (14), designed as a nozzle, is arranged so that the process gas can be sprayed between a plurality of parallel-arranged electrodes (32a, 32b) of the at least one receptive workpiece carrier (30).

12. An apparatus (1) for plasma-enhanced chemical vapor deposition having a process chamber (2) for receiving at least one workpiece carrier (30), comprising: configured to heat the process chamber (2) using at least one workpiece carrier (30) receivable in the process chamber (2); The apparatus (1) comprises a gas exhaust system (4) for creating a vacuum in the process chamber (2), the gas exhaust system (4) having a plurality of gas exhaust ports (11) arranged in the region of the bottom (12) of the process chamber (2) below the workpiece carrier (30) for drawing out gas when the workpiece carrier (30) is received.

13. 13. A system (50) for plasma-enhanced chemical vapor deposition, comprising the apparatus (1) according to any one of claims 1 to 12 and a workpiece carrier (30) by means of which a process chamber (2) of the apparatus (1) can be heated.

14. A method (100) for plasma-enhanced chemical vapor deposition, comprising: The workpiece carrier (30) is selectively connected to at least one heating voltage source (25) and is integrated into at least two heating circuits carrying low-frequency alternating current via a power supply connection (5) by a switching unit (22) so as to operate as a heating unit, The process chamber (2) is heated (S3) using at least one workpiece or workpiece carrier (30) receivable in the process chamber (2); the workpiece carrier (30) is selectively connected to a plasma voltage source (24) and integrated into a single plasma circuit carrying high frequency alternating current via the power supply connection (5) by the switching unit (22) so as to operate as a plasma unit; Method (100).

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