Process chamber for gas phase deposition of a semiconductor layer, device for gas phase deposition, method for heating substrates in a process chamber and method for gas phase deposition of a semiconductor layer

Abstract

The invention relates to a process chamber (10) for the gas phase deposition of a semiconductor layer, preferably a silicon layer, on a substrate (2), comprising at least one conductive carrier system (1, 1', 1") for transporting at least one substrate (2), preferably several substrates (2) simultaneously, in a transport direction (9) through the process chamber (10), wherein the carrier system (1, 1', 1") comprises a carrier plate (4) on which the at least one substrate (2) is arranged, a device for introducing process gases into the process chamber (10), and a heating system for resistance heating of the carrier system (1, 1', 1") and / or of the at least one substrate (2) arranged on the carrier system (1), wherein the carrier system (1, 1', 1") comprises at least two contact elements (3, 3') on diametrically opposite sides of the conductive carrier system (1, 1', 1") in order to contact the heating system (11).The process chamber is characterized by the feature that the heating system (11) has two busbars (6), at least one of which is a segmented busbar (6) having at least two segments (7, 7'), wherein at least one contact element (3, 3') is in contact with a busbar (6). Furthermore, the invention relates to a device for the gas phase deposition of a semiconductor material with a process chamber, a method for heating substrates in a process chamber, and a method for the gas phase deposition of a semiconductor layer, in particular a silicon layer, on a substrate.

Description

[0001] The invention relates to a process chamber for the gas-phase deposition of a semiconductor layer, preferably a silicon layer, on a substrate, comprising at least one carrier system for transporting at least one substrate in a transport direction through the process chamber, a device for introducing process gases into the process chamber, and a heating system for resistance heating the carrier system and / or the at least one substrate arranged on the carrier system, wherein the carrier system has at least two contact elements on diametrically opposite sides of the conductive carrier system for contacting the heating system. The invention further relates to a device for the gas-phase deposition of a semiconductor layer, preferably a silicon layer, on a substrate according to claim 21.Furthermore, the invention relates to a method for heating substrates in a process chamber according to claim 22 and a method for the gas phase deposition of a semiconductor layer, in particular a silicon layer, according to claim 23.

[0002] For large-area electronic components, such as large-area lighting elements or photovoltaic cells, but also for mass-produced products like semiconductor diodes, there is a need for cost-effective semiconductor wafers with high crystal quality, since in the case of such components, the material costs of the semiconductor wafer represent a considerable percentage of the total product cost. Methods for manufacturing semiconductor wafers are known in which wafers are produced from silicon blocks ("ingots") using a sawing process. This method makes it possible to produce high-quality, especially monocrystalline, semiconductor wafers. However, the production costs are high, partly due to material loss during the sawing of the silicon blocks.

[0003] Therefore, alternative processes were developed in which a wafer layer is deposited onto a substrate and then detached from the seed substrate. The detached wafer layer thus forms the semiconductor layer for the production of the electronic component. Substrate carriers are used to hold substrates, for example, for depositing semiconductor layers onto a seed substrate. The seed substrates are arranged on the substrate carrier. The substrate carrier is then moved into a process position within a process chamber, for example, by means of a process chamber guide.

[0004] Uniform heating of the substrates is essential for the growth of the semiconductor layer. Heating multiple substrates on a single support, as is currently the case, has the disadvantage that the temperature and heat distribution on the surface of the substrate, where the semiconductor layer is to be deposited, is not as uniform as desired. Furthermore, it is even more difficult to set the correct temperature and / or to maintain the correct temperature during the process, especially during a continuous process. In particular, the heating system itself influences the temperature distribution, as do the support and the elements that hold the substrate in place on the support.

[0005] For example, one method for heating substrates on a substrate carrier involves directly heating the substrate carrier by applying a current to it. However, applying a current to a substrate carrier while it is moving is quite difficult. In generic German patent DE 10 2011 017 566 A1, a substrate holder is disclosed, comprising a flat frame with at least one substrate holder for substrates to be treated, a contact means for electrically contacting the substrate holder, and at least one coupling plate that is attached to the frame by releasable fasteners in such a way that it holds the substrate in the substrate holder and thereby establishes a thermally conductive contact with the substrate and an electrical contact with the frame.

[0006] The present invention is therefore based on the objective of providing a simple and controllable method for heating substrates on a substrate holder by resistance heating. Furthermore, an objective of the present invention is to control the heating of the substrate holder more precisely and, in particular, to achieve a uniform heat distribution.

[0007] These and other tasks are accomplished by a process chamber for the gas-phase deposition of a semiconductor layer, in particular a silicon layer, on a substrate according to claim 1 and by a device for the gas-phase deposition of a semiconductor layer, in particular a silicon layer, on a substrate according to claim 21. Furthermore, these and other tasks are also accomplished by a method for heating substrates in a process chamber according to claim 22 and a method for the gas-phase deposition of a semiconductor layer, in particular a silicon layer, according to claim 23.

[0008] Advantageous embodiments of the process chamber are described in claims 2 to 20.

[0009] The process chamber for the gas-phase deposition of a semiconductor layer, preferably a silicon layer, on a substrate according to the present invention comprises at least one conductive carrier system for transporting at least one substrate, preferably several substrates simultaneously, in a transport direction through the process chamber, wherein the carrier system comprises a carrier plate on which the at least one substrate is arranged. Furthermore, the process chamber comprises a device for introducing process gases into the process chamber and a heating system for resistance heating the carrier system and / or the at least one substrate arranged on the carrier system, wherein the carrier system has at least two contact elements on diametrically opposite sides of the conductive carrier system for contacting the heating system.

[0010] The invention is characterized by the feature that the heating system has two busbars, at least one of which is a segmented busbar having at least two segments, wherein at least one contact element is in contact with a busbar.

[0011] The segmented busbar allows for better control of the current through the contact elements into the support system, and especially the support plate, thus preventing high currents. In particular, the segments of the segmented busbar can be individually controlled, enabling more precise temperature control of the support plate during its movement along the transport direction.

[0012] Preferably, the busbar for a live conductor is segmented, while the busbar for a neutral conductor is not segmented. In a preferred embodiment, both busbars are segmented within the process chamber. In a further preferred embodiment, the length of a segment of the neutral conductor can be twice the length of a segment of the live conductor. In yet another preferred embodiment, the lengths of the segments of the segmented busbar are substantially equal. The complexity of the process chamber is reduced by using substantially identical segments for the busbars.

[0013] In another preferred embodiment, the contact elements are arranged across the entire width of the carrier system. This connection ensures good contact between the carrier system and the contact element, particularly to achieve a uniform current distribution across the carrier system and the carrier plate. The width of the carrier system is essentially aligned along its transport direction.

[0014] In a preferred embodiment, the contact elements have at least one, preferably two, contact members that are in direct contact with the busbar. These contact members can be made of the same material as the contact element or of a different material with high conductivity, in particular a higher conductivity than that of the contact element.

[0015] Preferably, the contact element includes a bearing element. In particular, the bearing element is a plain bearing or a ball bearing. The bearing element, which is in direct contact with the busbar, especially the segmented busbar, enables smooth sliding or rolling on the surface of the busbar with reduced friction. A higher conductivity of the bearing element compared to the support system, and especially the support plate, is preferable. Alternatively, the element for electrical contact can also be separate from the elements for the movement of the support, e.g., as a sliding contact.

[0016] Alternatively, or preferably additionally, the contact element comprises a plate element with high conductivity, in particular with a higher conductivity than the carrier plate and / or the contact element itself. The plate element of the contact element is in direct contact with the busbar, in particular the segmented busbar. Preferably, the plate element has a low coefficient of friction, allowing the carrier system to move smoothly through the process chamber with reduced energy expenditure, thereby ensuring a good and secure connection between the plate element and the busbar. Additionally, the current can flow from the busbar into the carrier plate along the entire length of the plate element, thus preventing excessive heating of the contact element due to high currents flowing through it.

[0017] In a preferred embodiment, the length of a segment of the segmented busbar is comparable to or less than the width of the support system and / or the contact element and / or the contact member. In particular, the length of a segment of the segmented busbar is half the width of the support system and / or the contact element and / or the contact member. The width of the support system is essentially aligned along the transport direction of the support system.

[0018] In a further preferred embodiment, at least two segments of the segmented busbar are connected to the same power supply. In particular, two adjacent segments are connected to the same power supply; preferably, the power supply between the connected segments is switchable. By connecting adjacent segments to the same power source, the segments can be switched on and off depending on the position of the support system, especially the contact elements of the contact element. This allows for better control of the current flow into the support system and therefore better and more controllable heating of the support system.

[0019] In a further preferred embodiment, the segments can be switched depending on a position of the carrier system and / or a position of the contact elements along the transport direction.

[0020] Preferably, the busbars, in particular the segmented busbars, are arranged on diametrically opposite sides of the support system, in particular below and above the support system, if the support system and / or the at least one substrate are arranged vertically or almost vertically.

[0021] Preferably, the busbar is flexible in at least one direction, particularly perpendicular to the direction of transport. This flexibility ensures a good connection between the busbar and the contact element, and especially with the contact member, throughout the entire transport of the carrier system along the direction of transport. In particular, the busbar is flexible perpendicular to the direction of transport and / or in a plane perpendicular to the direction of transport. For example, if the carrier system is arranged substantially vertically, the busbar is flexible in a horizontal plane. Preferably, both busbars are flexible in at least one direction. Even more preferable is flexibility in parallel planes that are spaced apart from each other.

[0022] Alternatively, or preferably additionally, the busbar is cooled by the cooling device. Overheating of the busbar and unintentional heating of the support system by thermal radiation from the busbar can be avoided with a cooled busbar. In particular, the busbar is cooled by water cooling, by another cooling fluid such as oil, or by a gaseous cooling medium such as air.

[0023] Preferably, a contact element has at least two contact members that are spaced apart from each other. Multiple contact members allow for better control of the current flow into the carrier system.

[0024] Preferably, at least one contact element of the contact element is active for applying current, allowing the entire current for heating the carrier system to be transmitted via this at least one contact element. In this way, one contact element can be in contact with a current-carrying segment of the busbar, while another contact element of the same contact element can be in contact with a different segment of the segmented busbar, whose contact with the power supply is interrupted at that time. For this purpose, each contact element distributes the current evenly across the carrier plate.

[0025] Preferably, the process chamber includes means for monitoring the temperature of the substrates and / or the support systems, in particular the support plate. Examples of means for monitoring the temperature of the substrates and / or the support plate are temperature sensors, temperature-sensitive elements such as resistors, thermal imaging cameras, resistance sensors, or sensors for measuring the current flow through the busbars. Preferably, the specific resistance of the respective support system can be measured before or while the support system enters the process chamber.

[0026] Preferably, the at least one carrier system is continuously transported through the process chamber. Even more preferable is the continuous movement of the carrier systems into and out of the process chamber.

[0027] In a preferred embodiment, at least one contact element is arranged on a rear side of the support system, in particular on a rear side of the support plate, wherein the rear side is the surface side of the support system and / or the support plate that is free of substrates or on which the substrates are not arranged. Preferably, both contact elements are arranged on the rear side.

[0028] Alternatively, or preferably additionally, the contact elements are arranged on the side surfaces of the carrier plate facing the busbars. In particular, the contact elements are arranged above and below the carrier plate of the carrier system.

[0029] Preferably, the substrates can be arranged on both surface sides of the carrier plate, thus further increasing the capacity of the process chamber.

[0030] In a further preferred embodiment, the process chamber includes a control device designed to control at least the movement of the carrier system, the device for introducing process gases, and / or the heating system, and in particular the power supply. The control device allows the parts of the process chamber to be controlled in a coordinated manner. In particular, the movement of the carrier system, especially continuous movement, along the transport direction and the power supply to the segments of the busbar can be synchronized for uninterrupted and controlled heating of the carrier system.The means for monitoring the temperature can also be connected to the control device, so that, for example, the power supply to the segments can be adjusted depending on the temperature and / or the temperature distribution on the carrier plate and / or depending on variations in the material, material parameters, and / or the thickness of the individual carrier plates in different carrier systems. In particular, the current flow can be adjusted depending on the specific resistance of the carrier system. Alternatively or additionally, the temperature of the carrier plate can be adjusted by switching the power supply to the busbar, especially to the segments of the busbar, on and off, or by adjusting the current flow to the carrier plate.

[0031] Preferably, the process chamber has several carrier systems that are simultaneously connected in series. Preferably, the multiple carrier systems are moved continuously through the process chamber. The use of multiple carrier systems moving along the transport direction increases the number of substrates that can be processed. In particular, a continuous process can be established. Additionally, the at least one segmented busbar allows each carrier system to be heated individually. Specifically, the current flow through one carrier system can be controlled independently of the current flow through another carrier system, since these carrier systems are simultaneously connected to different segments of the segmented busbar. In this way, the temperature of each carrier system can be precisely controlled.Additionally, the at least one segmented power rail can provide a controllable, uninterrupted power supply during the movement of the support system.

[0032] In a further preferred embodiment, the carrier has a rib. The rib at least partially "frames" the carrier system and, in particular, the carrier plate. Preferably, the rib is arranged along the lateral surface of the carrier system, especially along a longitudinal direction of the carrier plate perpendicular to the transport direction. The rib increases the stability of the carrier system, particularly because the projecting edge can support the carrier plate like a frame, preferably together with the contact elements.

[0033] Preferably, the strip is made of an electrically non-conductive material. By using an electrically non-conductive material, such as quartz or ceramic material like aluminum oxide, short circuits with the environment of the process chamber or other support systems can be avoided, thus improving the safety of the system, especially for high current flows.

[0034] In a further preferred embodiment, the support plate has at least one region of different thickness. In particular, this region of different thickness is located outside the position of the at least one substrate, compared to the other parts of the support plate. Preferably, the region of increased thickness of the support plate is located towards the contact elements of the support system. These regions of increased thickness reduce the internal resistance, thus preventing rapid and significant heating of the support plate by applying high currents to the contact elements. In particular, the contact elements are attached directly to the regions of increased thickness of the support plate of the support system.

[0035] Preferably, the support plate has at least one recess for receiving the at least one substrate. In particular, the area for the at least one substrate within the support plate has the smallest thickness compared to other parts of the support plate. Heating of the at least one substrate can be enhanced in this embodiment. Preferably, each substrate is arranged in a recess of the support plate.

[0036] In another preferred embodiment, the support plate has a gradual decrease in thickness from one side to the other, particularly from top to bottom. Heat loss effects along the thickness gradient of the support plate can be compensated for, especially if the support plate is inclined towards a vertical plane.

[0037] Alternatively, or preferably additionally, the carrier plate is segmented into a plurality of parts. In particular, each part of the carrier plate can provide space for a substrate.

[0038] Preferably, the support system and / or the support plate is arranged vertically or horizontally in the process chamber. Alternatively, the support system and / or the support plate is inclined at an angle between 0° and 90°, preferably at an angle between 0° and 15°, relative to a vertical plane.

[0039] In a preferred embodiment, the carrier plate has a thickness between 1 mm and 30 mm, preferably between 5 mm and 20 mm. The thickness of the conductive carrier plate enables good resistance heating of the carrier plate.

[0040] Alternatively, or preferably additionally, the substrate has a coating, the coating preferably having a thickness between 10 µm and 200 µm, more preferably between 20 µm and 150 µm, and most preferably approximately 100 µm. Preferably, the thickness tolerance for the coating is approximately + / - 50 µm for a thickness of approximately 100 µm. Preferably, the coating consists of a semiconductor material, in particular silicon carbide (SiC). The coating increases the chemical stability and durability of the substrate and also prevents reactions between the substrate material, in particular graphite, and the surrounding area in the process chamber.

[0041] In a further preferred embodiment, the at least one contact element on one side of the carrier plate forms a fixed, detachable connection with the busbar, while the at least one contact element on the other side of the carrier plate forms a floating or sliding connection. The fixed, detachable connection of one contact element allows the carrier system to be easily replaced, particularly for maintenance or repair. Furthermore, a defective carrier system, especially one that does not ensure uniform heating of the substrate on the carrier system, can be removed and replaced with another.

[0042] Preferably, the contact members of the contact element have a hook-like structure for a firm, detachable connection.

[0043] Alternatively, or preferably additionally, the contact elements are made of a highly electrically conductive material, preferably a metal, in particular tungsten or tungsten carbide. Preferably, the contact elements have a higher conductivity than the carrier plate.

[0044] Preferably, the support plate is made of graphite or a graphite-containing material. Alternatively, or preferably additionally, the support plate can have a shape that differs from a flat, particularly plate-like, form. Preferably, both surface sides of the support plate can have different shapes, with one side of the support plate, preferably the side that receives the substrates, having a flat-like shape, and the other side having a texture, such as a meandering shape. The shape of the support plate can influence the heat distribution across the entire support plate for more uniform heating of the substrates on the support plate of the support system.

[0045] The object of the invention is also achieved by a device for the gas-phase deposition of a semiconductor layer, preferably a silicon layer, on a substrate, which comprises a process chamber or a preferred embodiment of the process chamber as mentioned above. The device for gas-phase deposition further comprises one or more sources for the required process gases, preferably a pumping system and preferably a means for monitoring the deposition process.

[0046] The object of the invention is also achieved by a method for heating substrates in a process chamber, as previously described, or by a preferred embodiment thereof, wherein at least one substrate is arranged on a carrier system and wherein several carrier systems are moved simultaneously along a transport direction through the process chamber. The method is characterized by the feature that a power supply for a segment of a segmented busbar is controlled depending on the position of the carrier system in the process chamber and / or depending on the temperature of the carrier plate of the carrier system and / or on the temperature of the at least one substrate on the carrier plate.

[0047] In particular, controlling the power supply for a segment of a segmented busbar involves switching the current on and off and / or adjusting the current flow for a specific segment. The temperature of the respective carrier system and the current flow into it can be controlled individually, allowing homogeneous conditions to be created for different carrier systems.

[0048] The object of the invention is also achieved by a method for the gas-phase deposition of a semiconductor layer, in particular a silicon layer, on a substrate, wherein the method is carried out in a gas-phase deposition apparatus as described above, wherein process gases are introduced into a process chamber of the apparatus to react on a surface of the substrate in order to build up the semiconductor layer on the at least one substrate, and wherein this method comprises a method for heating substrates in a process chamber as previously described. Due to the controlled heating of the at least one substrate on a support system, homogeneous conditions can be created for the substrates on different supports, so that the semiconductor layers are more uniform and of higher quality.

[0049] The advantages of the invention are explained by way of example with reference to embodiments and the figures. It shows: Fig. 1. A process chamber in a schematic side view with several support systems; and Fig. 2 a sectional view of a part of the support system around the contact element.

[0050] In Fig. Figure 1 schematically depicts a process chamber 10 for the gas-phase deposition of a silicon layer. Three carrier systems 1, 1', 1" are moved through the process chamber 10 along the transport direction 9. Several substrates 2 are mounted and housed on a carrier plate 4 on each carrier system 1, 1', 1". The carrier plate 4 is made of graphite and has a thickness of approximately 5 mm to 20 mm. Furthermore, the carrier plate 4 has a coating, preferably on all sides, at least on the surface where the substrates 2 are arranged. This coating is made of silicon carbide with a thickness of approximately 100 µm ± 50 µm. The coating prevents aging and degradation of the graphite carrier plate 4 due to chemical reactions in the atmosphere of the process chamber 10.To accommodate the substrates 2 on the carrier plate 4, the carrier plate 4 can have recesses where the thickness of the carrier plate 4 is reduced compared to other parts of the carrier plate 4. During the continuous transport of the carrier system 1, 1', 1" through the process chamber 10, the carrier plate 4 and the carrier systems 1, 1', 1" are arranged essentially perpendicularly.

[0051] During the transport of the substrates 2 on the carrier system 1, 1', 1" along the transport direction 9 through the process chamber 10, a silicon layer is deposited onto the substrates by means of vapor deposition. For the growth of the silicon layer on the substrates 2, the process chamber 10 also includes a device for introducing process gases into the process chamber 10, wherein the process gases are preferably directed towards the surface of the substrates (not shown). The process gases react on the surface of the substrates 2, resulting in a single-crystal silicon layer. The substrates 2 are also made of silicon and furthermore have a separating layer on their surface to facilitate the removal of the grown silicon layers from the substrates 2 at the end of the deposition process.

[0052] For the deposition of a silicon layer by vapor deposition onto a substrate 2 in a process chamber 10, heating the substrates 2 on the support system 1, 1', 1" is essential. To heat the substrates 2 on the support system 1, 1', 1" the process chamber 10 further comprises a heating system 11 for resistance heating the support system 1, 1', 1", in particular the support plate 4 or the substrates 2 on the support system 1, 1', 1". The heating system 11 has several power supplies 8, 8' and two busbars 6, which in the present embodiment are arranged above and below the support system 1, 1', 1" . The busbars 6 are segmented into several segments 7, 7', which are arranged side by side along the transport direction 9.The segments 7, 7' of both busbars 6, the main conductor which is arranged above the support systems 1, 1', 1" and the neutral conductor which is arranged below the support systems 1, 1', 1" are essentially identical, in particular essentially identical in their length.

[0053] To contact the busbar 6, the support system 1, 1', 1" has contact elements 3, 3' on diametrically opposite sides of the support system 1, 1', 1". The diametrically opposite sides of the support system 1, 1', 1" refer to sides of the support system 1, 1', 1" that are spaced apart from each other in the longitudinal direction of the support system 1, 1', 1", which is perpendicular to the transport direction 9. The contact elements 3, 3' are made of metal and are arranged substantially across the entire width of the support system 1, 1', 1" or the support plate 4. The width of the support system 1, 1', 1" extends substantially along the transport direction 9 of the support system 1, 1', 1". Due to the contact elements 3, 3' over the entire width of the carrier plate 4, a good and stable contact is achieved between the contact elements 3, 3' and the carrier plate 4.This results in an even distribution of the current flow through the carrier plate 4 and consequently in good heating of the carrier plate 4.

[0054] For the connection between the busbar 6 and the contact element 3, 3', each contact element 3, 3' further comprises two contact members 3a. In the present embodiment, the contact members 3a, which are spaced apart from one another, are formed by bearing elements in the form of rolling bearings. The use of rolling bearings as contact members 3a ensures smooth and, in particular, friction-reduced movement of the carrier system 1, 1', 1" in the process chamber 10 along the transport direction 9. Furthermore, the rolling bearings are made of a metal with high conductivity, so that the current flow is effectively directed into the carrier system 1, 1', 1". For a good conductive connection between the busbar 6 and the contact elements 3, 3' or contact members 3a, the busbar 6 is flexible in a direction perpendicular to the transport direction 9.In the present embodiment, the busbars 6 are flexible both in a direction into and out of the plane of the drawing, as well as along the longitudinal extension direction of the support plate 4 along the length of the support plate 4.

[0055] In the present embodiment of Fig. In this embodiment, two adjacent segments 7, 7' of the segmented busbar 6 are connected to the same power supply 8, 8', with the power being switched back and forth between the two adjacent segments 7, 7'. Switching the power supply from one segment 7, 7' to another segment 7, 7' depends on the position of the carrier system 1, 1', 1" and, in particular, on the position of the contact element 3a of the contact element 3, 3' along the transport direction 9. In this embodiment, current is supplied to one segment 7, 7' and flows only through one contact element 3a into the contact elements 3, 3' and the carrier plate 4 of the carrier system 1, 1', 1". In this way, only one contact element 3a is active for applying the current, and the entire current for heating the carrier system 1, 1', 1" is transmitted only through this one contact element 3a.The other contact element 3a is still in contact with the other segment 7, 7' of the busbar 6, with this segment being disconnected from the power supply 8, 8'. To prevent overheating of the segments 7, 7' of the busbar 6, these segments 7, 7', and in particular the entire busbar 6, can be cooled with a cooling device.

[0056] To prevent a short circuit between adjacent support systems 1, 1', 1", the support system 1, 1', 1" further comprises, at least partially, a strip 5 on its lateral surfaces, which is made of an electrically non-conductive material, such as aluminum oxide. The strip 5 is aligned along the longitudinal direction of the support plate 4 along the lateral surfaces. In the present embodiment, the lateral surfaces of the support system 1, 1', 1" are completely surrounded by the strip 5, with the exception of the lateral surfaces adjacent to the busbars 6, in order to prevent electrical contact between adjacent support systems 1, 1', 1". Furthermore, the strip 5 increases the stability of the support system 1, 1', 1", in particular because the strip 5 frames the support plate 4 together with the contact elements 3, 3'.

[0057] As mentioned above, the power supply 8, 8' for specific segments 7, 7' of the busbar 6 depends on the position of the carrier system 1, 1', 1" and, in particular, the contact element 3a. To control these processes, the process chamber 10 also includes a control device for controlling the movement of the carrier system 1, 1', 1", the heating system 11, and the device for introducing the necessary process gases. Depending on the position of the carrier system 1, 1', 1" along the transport direction 9, the segments 7, 7' of the segmented busbar 6 are connected to the power supply 8, 8' to achieve and maintain a specific temperature and temperature distribution of the carrier plate 4. Therefore, the power supply for the segments 7, 7' of the busbar can be switched on and off depending on the position of the carrier system 1, 1', 1" and / or the temperature and / or temperature distribution of the carrier plate 4 and / or the substrates 2.

[0058] To monitor the temperature of the carrier plate 4 and / or the substrates 2 on the carrier plate 4, the process chamber 10 is equipped with means for monitoring the temperature of the carrier plate 4 and / or the substrates 2, such as thermal imaging cameras. Depending on the temperature of the carrier plate 4 and / or the substrates 2 on the carrier plate 4, the current flow into the respective carrier system 1, 1', 1" is activated or deactivated and can be adjusted. Furthermore, the current flow itself can also be controlled depending on the temperature of the carrier plate 4 and / or the substrates 2 on the carrier plate 4 in order to achieve a previously set temperature of the carrier plate 4 and / or the substrates 2. The switching of the segments 7, 7' of the busbar 6 and, in particular, the current flow into the segments 7, 7' of the busbar 6 is also controlled by the control device.

[0059] Even when multiple carrier systems 1, 1', 1" are moved simultaneously in the process chamber 10 along the transport direction 9, the power supply for each carrier system 1, 1', 1" can be individually adjusted by increasing or decreasing the power of the power supply 8, 8' for segments 7, 7' of the segmented busbar 6. This enables an uninterrupted, yet controllable, power supply for each carrier system 1, 1', 1" during its movement along the transport direction 9. By controlling the power supply and current flow to the carrier system 1, 1', 1" the temperature of each carrier system 1, 1', 1" and, in particular, of each carrier plate 4 of the carrier systems 1, 1', 1" can also be controlled more precisely. The overall result is a better, more uniform, and higher-quality silicon layer deposited on the substrates 2.

[0060] In Fig. Figure 2 shows a more detailed view of the area around the contact element 3. In this embodiment, the contact element 3a is a rolling bearing that rolls in the busbar 6. The rolling bearing, as contact element 3a, is mounted in and surrounded by the contact element 3. The entire current flow directed into the contact element 3 and the carrier plate 4 passes through the rolling bearing. Alternatively, the contact element 3a can also be a sliding contact that is movable in the base of the busbar 6.

[0061] The contact element 3 is directly connected to the carrier plate 4. Since the contact element 3 has a thicker structure and is made of a material with higher conductivity than the carrier plate 4, on which the substrates 2 are arranged (e.g., metal), there is a transition zone in the carrier plate 4 where the thickness increases. This increased thickness of the carrier plate 4, compared to the main area on which the substrates 2 are arranged, prevents excessive heating of the carrier plate 4 due to the high currents flowing into it through the contact element 3.

[0062] An area around the further contact element 3' can be constructed in the same way or can differ from the one in Fig. The embodiment shown in Figure 2 differs. In particular, the further contact element 3' can only have a plate-like element as a contact member 3a for contacting the busbar 6, so that there is only a sliding or floating contact with the busbar 6.

[0063] In a further embodiment of the process chamber 10, which is not shown in detail, both contact elements 3, 3' comprise a plate element with high conductivity, for example made of tungsten carbide, as a contact member 3a. In particular, the contact element 3, 3' and the contact member 3a have a higher conductivity compared to the material of the carrier plate 4. The plate element as contact member 3a is arranged essentially in the middle of the width of the carrier system 1, 1', 1" and has a length that is essentially identical to the length of a segment 7, 7' of the segmented busbar 6.

[0064] Due to the elongated shape of the contact element 3a as a plate element, the current flows from the segmented busbar 6 into the carrier plate 4 along the entire length of the plate element, thus preventing excessive heating of the contact element 3a due to the high currents flowing through it. This is in contrast to the rolling bearing as contact element 3a, which in Fig. As shown in Figure 1, the plate element as contact member 3a remains cooler during the transport of the carrier systems 1, 1', 1" through the process chamber 10, since this plate element as contact member has a larger contact area with the busbar 6. Reference symbol list 1, 1', 1" carrier system 2 Substrat 3, 3' Contact element 3a Contact member 4 Carrier plate 5 bar 6 busbar 7.7' segments 8.8' Power supply 9. Transport direction 10th Trial Chamber 11 Heating system

Claims

[1] Process chamber (10) for the gas phase deposition of a semiconductor layer on a substrate (2), comprising at least one conductive carrier system (1, 1', 1") for transporting at least one substrate (2) in a transport direction (9) through the process chamber (10), wherein the carrier system (1, 1', 1") comprises a carrier plate (4) on which the at least one substrate (2) is arranged, a device for introducing process gases into the process chamber (10), and a heating system for resistance heating of the carrier system (1, 1', 1") and / or of the at least one substrate (2) arranged on the carrier system (1), wherein the carrier system (1, 1', 1") comprises at least two contact elements (3, 3') on diametrically opposite sides of the conductive carrier system (1, 1', 1") to contact the heating system (11), characterized by, that the heating system (11) has two busbars (6), at least one of which is a segmented busbar (6) having at least two segments (7, 7'), wherein at least one contact element (3, 3') is in contact with a busbar (6). [2] Process chamber (10) according to any of the preceding claims, characterized by , that the contact elements (3, 3') have at least one, preferably two contact members (3a) which are in direct contact with the busbar (6) and / or that the conductive carrier system (1, 1', 1") is designed to transport several substrates (2) simultaneously. [3] Process chamber (10) according to claim 2, characterized by that the contact member (3a) has a bearing element or a plate element with high conductivity, in particular with a conductivity that is higher compared to the carrier plate (4), wherein the plate element preferably has a low coefficient of friction. [4] Process chamber (10) according to one of the preceding claims, characterized by , that the length of a segment (7, 7') of the segmented busbar (6) has a length comparable to or less than the width of the support system (1, 1', 1"), in particular that the length of a segment (7, 7') of the segmented busbar (6) is half the width of the support system (1, 1', 1"). [5] Process chamber (10) according to any of the preceding claims, characterized by , that at least two segments (7', 7") are connected to the same power supply (8, 8'), in particular two adjacent segments (7', 7") are connected to the same power supply (8, 8'), preferably that the power supply (8, 8') between the connected segments (7', 7") is switchable. [6] Process chamber (10) according to any of the preceding claims, characterized bythat the conductor rail (6) is flexible in at least one direction, in particular perpendicular to the transport direction (9) and / or that the conductor rail (6) is cooled by a cooling device. [7] Process chamber (10) according to any of the preceding claims, characterized by , that the segments (7, 7') can be switched depending on a position of the carrier system (1, 1', 1"). [8] Trial chamber at least according to claim 2, characterized by , that the segments (7, 7') can be switched depending on a position of the contact elements (3a) along the transport direction (9) and / or that the at least one contact element (3a) of the contact element (3, 3') is active for applying a current, whereby the entire current for heating the carrier system (1, 1', 1") is transmitted via at least one contact element (3a). [9] Process chamber (10) according to any of the preceding claims, characterized by, that the process chamber (10) has a control device which is configured to control at least the movement of the carrier system (1, 1', 1"), the device for introducing process gases and / or the heating system (11) and in particular the power supply (8, 8'). [10] Process chamber (10) according to any of the preceding claims, characterized by , that the process chamber (10) has several support systems (1, 1', 1") which are used simultaneously in series. [11] Process chamber (10) according to any of the preceding claims, characterized by , that the support system (1, 1', 1") has a strip (5) which is made in particular of an electrically non-conductive material. [12] Process chamber (10) according to any of the preceding claims, characterized by, that the support plate (4) has at least one area of ​​a different thickness, in particular that an area outside the arrangement of the at least one substrate has an increased thickness, preferably that the area of ​​increased thickness of the support plate (4) is arranged towards the contact elements (3, 3') of the support system (1, 1', 1"). [13] Process chamber (10) according to any of the preceding claims, characterized by , that the support plate (4) has recesses for receiving the at least one substrate (2), in particular that the area for the at least one substrate (2) has the smallest thickness in the support plate (4). [14] Process chamber (10) according to any of the preceding claims, characterized by, that the support plate (4) has a gradual decrease in thickness from one side to the other, in particular from top to bottom when the support plate (4) is oriented vertically in the process chamber (10), and / or that the support plate (4) is segmented into several parts. [15] Process chamber (10) according to any of the preceding claims, characterized by , that the support system (1, 1', 1") and / or the at least one support plate (4) is arranged vertically or horizontally in the process chamber (10) or is inclined at an angle between 0° and 90°, preferably at an angle between 0° and 15°, relative to a vertical plane. [16] Process chamber (10) according to any of the preceding claims, characterized by, that the carrier plate (4) has a thickness between 1 mm and 30 mm, preferably between 5 mm and 20 mm and / or that the carrier plate (4) has a coating, wherein the coating preferably has a thickness between 10 µm and 200 µm, more preferably between 20 µm and 150 µm, and even more preferably approximately 100 µm. [17] Process chamber (10) according to claim 16, characterized by that the coating consists of a semiconductor material, in particular SiC. [18] Process chamber (10) according to any of the preceding claims, characterized by , that the at least one contact element (3, 3') on one side of the carrier plate (4) forms a fixed, detachable connection with the busbar (6), wherein the at least one contact element (3, 3') on another side of the carrier plate (4) forms a floating or sliding connection. [19] Process chamber (10) according to any of the preceding claims, characterized by, that the contact members (3a) of the contact element (3, 3') have a hook-like structure for a fixed, detachable connection and / or that the contact elements (3, 3') are made of a highly electrically conductive material, preferably a metal. [20] Process chamber (10) according to any of the preceding claims, characterized by that the support plate (4) is made of graphite or a graphite-containing material. [21] Device for gas phase deposition of a semiconductor material, in particular a silicon layer, on a substrate (2), comprising a process chamber (10) according to one of the preceding claims. [22] Method for heating substrates (2) in a process chamber (10) according to any one of claims 1 to 20, wherein at least one substrate (2) is arranged on the carrier system (1, 1', 1") and several carrier systems (1, 1', 1") are moved simultaneously along a transport direction (9) through the process chamber (10), characterized by , that a power supply (8, 8') for a segment (7, 7') of the at least one segmented busbar (6) is controlled depending on the position of the carrier system (1, 1', 1") in the process chamber (10) and / or depending on a temperature of the carrier plate (4) of the carrier system (1, 1', 1") and / or on a temperature of the substrates (2) on the carrier plate (4). [23] Method for gas-phase deposition of a semiconductor layer, in particular a silicon layer, on a substrate (2), wherein the method is carried out in an apparatus according to claim 21, and wherein process gases are introduced into the process chamber (10) of the apparatus to react on a surface of the substrate (2) in order to build up the semiconductor layer on the substrate, characterized by , that the method comprises a method for heating substrates (2) in a process chamber (10) according to claim 22.

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