Abstract: An apparatus for depositing a material layer originating from process gas on a substrate wafer, contains: a reactor chamber delimited by an upper dome, a lower dome, and a side wall; a susceptor for holding the substrate wafer during the deposition of the material layer; a preheating ring surrounding the susceptor; a liner, on which the preheating ring is supported in a centered position wherein a gap having a uniform width is present between the preheating ring and the susceptor; and a spacer acting between the liner and the preheating ring, the spacer keeping the preheating ring in the centered position and providing a distance ? between the preheating ring and the liner.

Abstract: Granular silicon which is especially useful in reducing dislocations and gas inclusions of single crystals prepared therefrom is produced by a heat treatment in which a process gas flowing through a plasma chamber heats granular silicon, and the heated granular silicon is transported counter-currently through the plasma chamber, melting an outer periphery of the granular silicon, which then recrystallizes, producing an exterior with a lower concentration of crystal grains than the interior of the granules.

Abstract: An apparatus for producing a single crystal of silicon comprises a plate with a top side, an outer edge, and an inner edge, a central opening adjoining the inner edge, and a tube extending from the central opening to beneath the bottom side of the plate; a device for metering granular silicon onto the plate; a first induction heating coil above the plate, provided for melting of the granular silicon deposited; a second induction heating coil positioned beneath the plate, provided for stabilization of a melt of silicon, the melt being present upon a growing single crystal of silicon. The top side of the plate consists of ceramic material and has elevations, the distance between the elevations in a radial direction being not less than 2 mm and not more than 15 mm.

Abstract: A crystal of semiconductor material is produced in an apparatus having a crucible with a crucible bottom and a crucible wall, the crucible bottom having a top surface, an underside, and a multitude of openings disposed between the crucible wall and a center of the crucible bottom, and elevations disposed on the top surface and the underside of the crucible bottom; and an induction heating coil disposed below the crucible for melting semiconductor material and stabilizing a melt of semiconductor material covering a growing crystal of semiconductor material. The growth process comprises generating a bed of a semiconductor material feed on the top surface of the crucible bottom and melting semiconductor material on the bed using the induction heating coil.

Abstract: A silicon single crystal is produced by a method wherein a silicon plate is inductively heated; granular silicon is melted on the silicon plate; and the molten silicon thus produced flows through a flow conduit in the center of the plate to a phase boundary at which a silicon single crystal crystallizes, wherein a silicon ring having a lower resistivity than the plate, and lying on the plate, is inductively heated prior to inductively heating the plate, and melting the ring.

Abstract: A crystal of semiconductor material is produced in an apparatus having a crucible with a crucible bottom and a crucible wall, the crucible bottom having a top surface, an underside, and a multitude of openings disposed between the crucible wall and a center of the crucible bottom, and elevations disposed on the top surface and the underside of the crucible bottom; and an induction heating coil disposed below the crucible for melting semiconductor material and stabilizing a melt of semiconductor material covering a growing crystal of semiconductor material. The growth process comprises generating a bed of a semiconductor material feed on the top surface of the crucible bottom and melting semiconductor material on the bed using the induction heating coil.

Abstract: An apparatus for producing a single crystal of silicon comprises a plate with a top side, an outer edge, and an inner edge, a central opening adjoining the inner edge, and a tube extending from the central opening to beneath the bottom side of the plate; a device for metering granular silicon onto the plate; a first induction heating coil above the plate, provided for melting of the granular silicon deposited; a second induction heating coil positioned beneath the plate, provided for stabilization of a melt of silicon, the melt being present upon a growing single crystal of silicon. The top side of the plate consists of ceramic material and has elevations, the distance between the elevations in a radial direction being not less than 2 mm and not more than 15 mm.

Abstract: Uniformity of vapor deposited coatings on semiconductor wafers is improved by employing an apparatus having a gas distributor head below a susceptor onto which the wafer is placed, the gas distributor head directing a fan of cooling gas at the rear side of the susceptor. The ratio of the diameter of the cooled section of the susceptor to the diameter D of the wafer is preferably from 0.1 to 0.4.

Abstract: A layer is deposited onto a semiconductor wafer by CVD in a process chamber having upper and lower covers, wherein the wafer front side temperature is measured; the wafer is heated to deposition temperature; the temperature of the upper process chamber cover is controlled to a target temperature by measuring the temperature of the center of the outer surface of the upper cover as the value of a controlled variable of an upper cover temperature control loop; a gas flow rate of process gas for depositing the layer is set; and a layer is deposited on the heated wafer front side during control of the upper cover temperature to the target temperature. A process chamber suitable therefor has a sensor for measuring the upper cover outer surface center temperature and a controller for controlling this temperature to a predetermined value.

Abstract: Uniformity of vapor deposited coatings on semiconductor wafers is improved by employing an apparatus having a gas distributor head below a susceptor onto which the wafer is placed, the gas distributor head directing a fan of cooling gas at the rear side of the susceptor. The ratio of the diameter of the cooled section of the susceptor to the diameter D of the wafer is preferably from 0.1 to 0.4.

Abstract: A silicon single crystal is produced by a method wherein a silicon plate is inductively heated; granular silicon is melted on the silicon plate; and the molten silicon thus produced flows through a flow conduit in the center of the plate to a phase boundary at which a silicon single crystal crystallizes, wherein a silicon ring having a lower resistivity than the plate, and lying on the plate, is inductively heated prior to inductively heating the plate, and melting the ring.

Abstract: A layer is deposited onto a semiconductor wafer by CVD in a process chamber having upper and lower covers, wherein the wafer front side temperature is measured; the wafer is heated to deposition temperature; the temperature of the upper process chamber cover is controlled to a target temperature by measuring the temperature of the center of the outer surface of the upper cover as the value of a controlled variable of an upper cover temperature control loop; a gas flow rate of process gas for depositing the layer is set; and a layer is deposited on the heated wafer front side during control of the upper cover temperature to the target temperature. A process chamber suitable therefor has a sensor for measuring the upper cover outer surface center temperature and a controller for controlling this temperature to a predetermined value.

Abstract: An incorrect position of a semiconductor wafer during thermal treatment in a process chamber heated by means of infrared emitters and transmissive to infrared radiation is identified, wherein the semiconductor wafer lies in a circular pocket of a rotating susceptor and is held at a predetermined temperature with the aid of the infrared emitters and a control system, and wherein thermal radiation is measured by a pyrometer, an amplitude of the fluctuations of the measurement signal is determined and an incorrect position of the semiconductor wafer is assumed if the amplitude exceeds a predetermined maximum value. The pyrometer is oriented such that the measurement spot detected by the pyrometer lies partly on the semiconductor wafer and partly outside the semiconductor wafer on the susceptor so that it is possible to identify an eccentric position of the semiconductor wafer within the pocket of the susceptor.

Abstract: An apparatus for depositing a material layer originating from process gas on a substrate wafer, contains: a reactor chamber delimited by an upper dome, a lower dome, and a side wall; a susceptor for holding the substrate wafer during the deposition of the material layer; a preheating ring surrounding the susceptor; a liner, on which the preheating ring is supported in a centered position wherein a gap having a uniform width is present between the preheating ring and the susceptor; and a spacer acting between the liner and the preheating ring, the spacer keeping the preheating ring in the centered position and providing a distance ? between the preheating ring and the liner.

Abstract: A method for depositing a layer on a semiconductor wafer using chemical vapor deposition (CVD). The method includes providing a chamber having an inlet opening and an outlet opening and a channel joining the inlet opening and the outlet opening, wherein the channel is bounded at the bottom by a plane and at the top by a window transmissive to thermal radiation. A semiconductor wafer is disposed so that a surface of the semiconductor lies in the plane, wherein the window has a center region disposed over the semiconductor wafer and an edge region surrounding the center region and not disposed over the semiconductor wafer. A distance between the plane and the window varies across the chamber, the distance being greater at the edge region than at the center region. A tangent applied to a radial profile of the distance at a boundary between the center region and the edge region forms an angle with the plane of not less than 15° and not more than 25°.

Abstract: Silicon wafers polished on their front sides are individually placed on a susceptor in an epitaxy reactor and firstly pretreated under a hydrogen atmosphere, and secondly with addition of an etching medium with a flow rate of 1.5-5 slm to the hydrogen atmosphere, the hydrogen flow rate being 1-100 slm in both steps, and subsequently epitaxially coated on the polished front side, and then removed from the reactor. In a second method, gas flows introduced into the reactor by injectors are distributed into outer and inner zones of the chamber, such that the inner zone gas flow acts on a wafer central region and the outer zone gas flow acts on a wafer edge region, the inner/outer distribution of the etching medium I/O=0-0.75. Silicon wafers having an epitaxial layer having global flatness value GBIR of 0.02-0.06 ?m, relative to an edge exclusion of 2 mm are produced.

Abstract: An incorrect position of a semiconductor wafer during thermal treatment in a process chamber heated by means of infrared emitters and transmissive to infrared radiation is identified, wherein the semiconductor wafer lies in a circular pocket of a rotating susceptor and is held at a predetermined temperature with the aid of the infrared emitters and a control system, and wherein thermal radiation is measured by a pyrometer, an amplitude of the fluctuations of the measurement signal is determined and an incorrect position of the semiconductor wafer is assumed if the amplitude exceeds a predetermined maximum value. The pyrometer is oriented such that the measurement spot detected by the pyrometer lies partly on the semiconductor wafer and partly outside the semiconductor wafer on the susceptor so that it is possible to identify an eccentric position of the semiconductor wafer within the pocket of the susceptor.

Abstract: Silicon wafers polished on their front sides are individually placed on a susceptor in an epitaxy reactor and firstly pretreated under a hydrogen atmosphere, and secondly with addition of an etching medium with a flow rate of 1.5-5 slm to the hydrogen atmosphere, the hydrogen flow rate being 1-100 slm in both steps, and subsequently epitaxially coated on the polished front side, and then removed from the reactor. In a second method, gas flows introduced into the reactor by injectors are distributed into outer and inner zones of the chamber, such that the inner zone gas flow acts on a wafer central region and the outer zone gas flow acts on a wafer edge region, the inner/outer distribution of the etching medium I/O=0-0.75. Silicon wafers having an epitaxial layer having global flatness value GBIR of 0.02-0.06 ?m, relative to an edge exclusion of 2 mm are produced.

Abstract: A method for depositing a layer on a semiconductor wafer using chemical vapor deposition (CVD). The method includes providing a chamber having an inlet opening and an outlet opening and a channel joining the inlet opening and the outlet opening, wherein the channel is bounded at the bottom by a plane and at the top by a window transmissive to thermal radiation. A semiconductor wafer is disposed so that a surface of the semiconductor lies in the plane, wherein the window has a center region disposed over the semiconductor wafer and an edge region surrounding the center region and not disposed over the semiconductor wafer. A distance between the plane and the window varies across the chamber, the distance being greater at the edge region than at the center region. A tangent applied to a radial profile of the distance at a boundary between the center region and the edge region forms an angle with the plane of not less than 15° and not more than 25°.

Abstract: A method and a device for regulating a pressure in an epitaxy reactor, wherein the epitaxy reactor has a wafer handling chamber WHC, a process chamber PC, and a gate valve GV connecting the two chambers. The wafer handling chamber is continuously purged with inert gas. The pressure difference between the wafer handling chamber and the process chamber is measured, and the resulting measurement signal is used in a control circuit to regulate the pressure in the wafer handling chamber. In this case the pressure in the wafer handling chamber is reduced if the pressure difference is above a predetermined value and the pressure in the wafer handling chamber is increased if the pressure difference is below a predetermined value. The predetermined pressure difference is defined as a pressure being between 5 and 500 PA. The WHC and the PC each have a gas discharge line and a gas input line.