AIXTRON SE

In the thermal treatment of substrates, a susceptor is used to hold at least one substrate. The susceptor can be heated with a heater and driven in rotation about a rotation axis by a rotary drive. Means are provided to influence the heat transfer to or from the susceptor in a locally limited manner, synchronized with the rotary movement of the susceptor, to equalize local temperature differences on the rotating susceptor. In particular, a temperature control gas with changing heat conduction properties is periodically fed in a pulsed manner through a feed opening into a gap between the susceptor and a cooling unit.

In the thermal treatment of substrates, a susceptor is used to hold at least one substrate. The susceptor can be heated with a heater and driven in rotation about a rotation axis by a rotary drive. Means are provided to influence the heat transfer to or from the susceptor in a locally limited manner, synchronized with the rotary movement of the susceptor, to equalize local temperature differences on the rotating susceptor. In particular, a temperature control gas with changing heat conduction properties is periodically fed in a pulsed manner through a feed opening into a gap between the susceptor and a cooling unit.

An assembly for providing a process gas for use in a CVD reactor includes an inlet mass flow controller for providing a carrier gas flow which flows into an evaporation device. The carrier gas flow conveys the vapor of a starting material from a container of the evaporation device through a process gas feed line to the CVD reactor. The total pressure in the process gas feed line can be held at a predefined value by a pressure controller. In order to hold the mass flow of the starting material, which mass flow is to be fed into the CVD reactor, sufficiently constant over time, the gas stream flowing through the process gas feed line is controlled by a mass flow controller, and the concentration of the starting material in the process gas feed line at a predefined total pressure is measured.

In a CVD reactor and a method for the open-loop/closed-loop control of the surface temperature of substrates arranged therein, the substrates lie on substrate-retaining elements, which are each supported by a gas cushion. Actual values of the surface temperatures associated with a respective substrate-retaining element are successively measured and the surface temperatures are controlled in a closed-loop manner to a common value by varying the gas cushion height. After measuring each actual value of the surface temperature associated with a substrate-retaining element and using only the respective last-measured actual value of the surface temperatures of each substrate-retaining element, a first average value is calculated, a difference value associated with the substrate-retaining element is calculated, and an approximate actual value is calculated for each of the other substrate-retaining elements by adding the associated difference value to the first average value, said approximate actual value being used for the open-loop/closed-loop control.

A susceptor for a CVD reactor includes a bearing surface for supporting a substrate holder. A carrier gas is fed into an inner radial zone, in order to floatingly cushion a substrate holder supported above the bearing surface. The gas fed into the inner radial zone leaves a second radial zone through discharge channels and to a slight extent through a gap surrounding the second radial zone and assigned to a third radial zone. The cross-sectional area of the discharge channels and the radial length of the gap are dimensioned such that the volumetric flow of the gas through the discharge channels is greater than through the gap if the latter has a gap height of 200 μm.

Information is communicated to a process control device by performing a process that includes the step of heating a component, the component having structured volumetric regions. When the component is heated, structures present in the volumetric regions radiate in the infrared spectrum, allowing the structures to be distinguished by an infrared sensor. The structures, formed by elevations or depressions, form a machine-readable identifier, which can be used as an originality identification means for the component. Since the identifier can be determined in situ during a heating process, the process control device can recognize whether correction values are to be used for the thermal treatment of a substrate.

A component made of a quartz blank is used as a component part of a CVD reactor. At least one cavity of the component is created by selective laser etching, wherein a fluid flows through the at least one cavity. When in use, the component is heated to temperatures in excess of 500° C., and comes into contact with hydrides of the main groups IV, V or VI and/or with organometallic compounds or halogenides of elements of the main groups II, III or V.

A CVD reactor includes a gas inlet member having a circular outline, and a susceptor that can be heated by a heating device. The gas inlet member has a cooled ceiling panel with outlet openings. The CVD reactor further comprises a shield plate, which adjoins the ceiling panel and has a circular outline. The shield plate has a central zone, an annular zone surrounding the central zone, having a rear side that points toward the ceiling panel, and a flat gas outlet surface pointing toward the process chamber, in which gas outlet openings terminate. The rear side in the central zone defines a rear plane running parallel to the gas outlet surface. The shield plate has a material thickness between 3 to 12 mm, and that the shield plate is spaced apart from the ceiling plate by a gap having a height between 0.3 to 1 mm.

A gas outlet surface of a gas inlet element for a CVD reactor or a gas outlet surface of a shielding plate for a gas inlet element has a multiplicity of gas outlet openings arranged around a center of the gas outlet surface. The central points of the gas outlet openings lie at the corner points of polygonal, identically formed cells, each having a geometrical central point. The position and the length of the edges of the cells are defined by intersecting reference lines, the reference lines being assigned to at least two families of lines, and the reference lines of a respective family extending linearly and parallel to one another over an entirety of the gas outlet surface. The center of the gas outlet surface is separated from one of the corner points by one-third±10 percent of the length of one of the edges.

A gas-inlet element for a CVD reactor includes a gas distribution volume arranged rearward of a gas outlet plate, from which volume pipes having end portions protruding from the gas outlet plate on the front side emerge. The pipes extend into through openings in a shield plate assembly extending parallel to the gas outlet plate. The through openings have a first portion facing the gas outlet plate with a large diameter which is larger than the outer diameter of the respective end portions, and a second portion facing away from the gas outlet plate with a smaller diameter. In order to prevent temperature non-uniformities in the region of the through openings, the diameter of the second portion is smaller than the outer diameter of the respective end portions. The shield plate arrangement additionally consists of two shield plates with different thermal conductivities arranged one above another.