Abstract: An infrared ray lamp having a structure wherein a groove is formed in the vicinity of each of both end portions of a substantially plate heating element formed of a carbon-based substance, a carbon-based adhesive is applied to a region including the groove, and the end portion of the heating element is inserted into a slit formed at the end portion of a heat-emitting block having high conductivity so as to be sandwiched; by forming a reflection film on the glass tube of the infrared ray lamp, an infrared ray lamp having a desired emission intensity distribution is provided; a heating apparatus using this infrared ray lamp and method of producing the infrared ray lamp are also provided.

Abstract: An apparatus for processing a semiconductor substrate is provided. The apparatus comprises a process chamber having a plurality of walls and a substrate support to support the substrate within the process chamber. A radiative heat source is positioned outside the process chamber to heat the substrate through the walls when the substrate is positioned on the substrate support. In some embodiments, lenses are provided between the heat source and the substrate to focus or diffuse radiation from the heat source and thereby selectively alter the radiation intensity incident on certain portions of the substrate. In other embodiments, diffusing surfaces are provided between the heat source and the substrate to diffuse radiation from the heat source and thereby selectively reduce the radiation intensity incident on certain portions of the substrate.

Abstract: A heating device of the light irradiation type in which uniform illuminance can be obtained without placing a single end lamp in the middle of the light source part is achieved providing a light source part in which circular lamps are arranged concentrically to one another with a mirror in the center of the circular lamps. The mirror is convex toward the workpiece and reflects the light emitted from the innermost circular lamp located closest to the center area so that, without placing a single end lamp in the middle area, the reduction of illuminance in the middle area of the irradiated surface is reduced. Furthermore, the reflector can be made conical, and in this way, the light from the lamps can be emitted with high efficiency onto the workpiece surface.

Abstract: A heating lamp bracket for reaction chambers of evaporation coating machines. The heating lamp bracket uses paired and insulation devices to mount heating lamps to a chamber wall of a reaction chamber. The bracket includes a mounting frame that has an insulation outer surface and a mounting outer face opposing to the insulation outer surface. The insulation outer surface has at least one insulation member located thereon for fastening the mounting frame to the chamber wall. The mounting outer surface has at least two independent mounting spots for connecting respectively a connection end of the corresponding heating lamp. The independent mounting spots and non-encased type insulation members of the present invention allows for the replacement of the heating lamps and defective insulation.

Abstract: A wafer support system comprising a segmented susceptor having top and bottom sections and gas flow passages therethrough. A plurality of spacers projecting from a recess formed in the top section of the susceptor support a wafer in spaced relationship with respect to the recess. A sweep gas is introduced to the bottom section of the segmented susceptor and travels through the gas flow passages to exit in at least one circular array of outlets in the recess and underneath the spaced wafer. The sweep gas travels radially outward between the susceptor and wafer to prevent back-side contamination of the wafer. The gas is delivered through a hollow drive shaft and into a multi-armed susceptor support underneath the susceptor. The support arms conduct the sweep gas from the drive shaft to the gas passages in the segmented susceptor. The gas passages are arranged to heat the sweep gas prior to delivery underneath the wafer.

Abstract: A thermal processing system performs predetermined thermal processing on an approximately circular to-be-processed object, by applying radiant heat to the to-be-processed object by means of a heating lamp system. The heating lamp system comprises a plurality of lamps disposed concentrically so as to correspond to the to-be-processed object. The plurality of lamps are controlled individually for respective zones of the to-be-processed object.

Abstract: Disclosed is a heat treating method for heating a target substrate by means of light irradiation, in which a light irradiation treatment is applied to the target substrate a plurality of times such that adjacent light irradiated regions on the target substrate partially overlap with each other and that the adjacent light irradiated regions do not overlap with each other in the light irradiating periods.

Abstract: The present invention relates to an oven that includes both radiant cooking elements and a microwave cooking element. The cooking elements are controlled to provide reduced cooking time as compared to known radiant ovens, yet a wide variety of foods can be cooked in the oven. The oven is operable in a speed cooking mode wherein both radiant and microwave cooking elements are utilized, a microwave only cooking mode wherein only the magnetron is utilized, and a radiant only cooking mode wherein only the lamps are utilized.

Abstract: A radiant energy device for shrinking a thin film onto an open top of a container, the radiant energy device comprising: a source of power, to provide power to the radiant energy device; a plurality of fixed energy-emitting units, each of the units when energized being configured to emit radiant energy towards the shrinking film on said open top of the container; and a switching means, operatively connected between the source of power and each of the energy-emitting units, to independently activate at least two groups of the energy-emitting units; wherein, a first group of the energy-emitting units partially shrinks the thin film onto the container, and a second group finishes the shrinking.

Abstract: An apparatus for processing a substrate comprises a susceptor for supporting the substrate, an upper heat source spaced above the susceptor, a lower heat source spaced below the susceptor, and a controller. The controller provides power to the heat sources at a selected ratio between the sources. The controller is configured to vary the ratio during a high temperature processing cycle of a substrate to thereby vary the ratio of the heat provided by the heat sources during the cycle.

Abstract: A reactor chamber is positioned between a top array of heat lamps and a bottom array of heat lamps. At least one of the heat lamps forming the top and bottom arrays features a segmented filament such that power output along the length of the heat lamp differs. In one configuration, the heat lamp has a pair of high energy output regions spaced from each other by a lower energy output region. In some configurations, at least one of the heat lamps forming the top and bottom arrays is non-linear, such as U-shaped. In further configurations, a non-linear heat lamp has a segmented filament with segments or areas of different winding density.

Abstract: Disclosed is a heat treating method for heating a target substrate by means of light irradiation, in which a light irradiation treatment is applied to the target substrate a plurality of times such that adjacent light irradiated regions on the target substrate partially overlap with each other and that the adjacent light irradiated regions do not overlap with each other in the light irradiating periods.

Abstract: The apparatus provides a temperature controlled environment for processing semiconductor wafers at elevated temperatures. A hot wall process chamber is used for the process steps. The process chamber includes three zones with independent temperature control capabilities. The apparatus is capable of rotating the wafer in addition to providing a gas flow velocity gradient above the wafer for improved temperature and processing uniformity results.

Abstract: An apparatus for heat treating semiconductor wafers is disclosed. In accordance with the present invention, the apparatus includes a temperature measuring system for determining the temperature of semiconductor wafers being heated within the apparatus. The temperature measurement system includes a shield member made from, for instance, ceramic which is placed adjacent to the semiconductor wafer being heated. A temperature measuring device, such as a thermocouple, is placed in association with the shield member. As the wafer is heated, the temperature of the shield member is monitored. Based on a predetermined calibration curve, by knowing the temperature of the shield member, the temperature of the semiconductor wafer can be estimated with reasonable accuracy.

Abstract: The invention provides a system for providing a flow of a short-lived, reactive process gas species into an RTP chamber without creating ionic species. An RTP chamber includes a transparent quartz window assembly. The window assembly has a first pane facing a wafer inside the RTP chamber. A second pane is positioned adjacent a heat lamp array on the outside of the RTP chamber. A window side wall joins the first and second panes at their peripheral edges to provide an internal chamber therebetween. A plurality of channels extend through the first pane from the internal chamber to the inside of the RTP chamber. A port communicates between the internal chamber and a process gas source. The window assembly also includes a reflective surface facing the internal chamber. An ultraviolet light source is positioned to illuminate process gas flowing through the window assembly with ultraviolet light such that the ultraviolet light alters the chemistry of the process gas.

Abstract: An apparatus and method is disclosed for sealing a filter element to a support member. An array of bonding fibers is interposed between the filter element and the support member. Infrared energy is applied for a period of time sufficient to at least partially melt the array of bonding fibers to sinter bond the filter element to the support member.

Abstract: A short-wave infrared surface radiator, with at least one infrared radiator, is equipped with a cladding tube. The cladding tube encloses, in a vacuum-tight manner, a heating element, which has an electric connection that is guided out of the cladding tube on a connection-side end via a pinch on a face of the cladding tube. A molybdenum foil is sealed into the cladding tube. Several infrared radiators that are connected to each other are arranged in an adjacent and parallel design while forming a joint radiating plane, with the connection-side end of the cladding tubes each being angled with regard to the radiating plane. The cladding tubes are fused together in an area of their front side that is opposite an angled section.

Abstract: A novel rapid thermal process (RTP) barrel reactor processes a larger batch of semiconductor substrates than was previously possible. The RTP barrel reactor is characterized by a short process cycle time in comparison to the same process cycle time in a conventional CVD barrel reactor. A rapid heat-up of the substrates is one of the keys to the shorter process cycle times of the RTP barrel reactor. The RTP barrel reactor utilizes a radiant heat source in combination with a heat controller that includes an open-loop controller for heat-up and a closed-loop controller for deposition as well as a new energy stabilizer to achieve heating a larger energy stabilizer and volume to a uniform processing temperature in times characteristic of RTP reactors.

Abstract: A dual surfaced mid-reflector employs two independently shaped faceted faces to direct radiant energy from separate heater lamp arrays to a substrate or substrate support to be heated. A dual surfaced mid-reflector can also be employed in conjunction with a peripheral cylindical reflect or and a central cylindrical reflector to further direct radiation to specific regions on a substrate or substrate support. In addition, a dual surfaced mid-reflector can also be employed in conjunction with heater lamps where the radiation of individual lamps is further directed by focusing reflectors or dispersive reflectors.

Abstract: A thermal processor for at least one semiconductor wafer includes a reactor chamber having a material substantially transparent to light including a wavelength within the range of about 200 nanometers to about 800 nanometers for holding the at least one semiconductor wafer. A coating including a material substantially reflective of infrared radiation can be present on at least a portion of the reactor chamber. A light source provides radiant energy to the at least one semiconductor wafer through the coating and the reactor chamber. The light source can include an ultraviolet discharge lamp, a halogen infrared incandescent lamp, or a metal halide visible discharge lamp. The coating can be situated on an inner or outer surface of the reactor chamber. If the reactor chamber has inner and outer walls, the coating can be situated on either the inner wall or the outer wall.

Abstract: A method of conveying moieties through an infrared conveyor furnace with controllable point source radiation elements incorporating a clean room internal environment. The method comprises the steps of transporting moieties in an indexed manner through multiple heating zones heated by arrays of lamps; and dividing the lamps of each array into a plurality of groups which are separately controlled to maintain a constant temperature across the surface of the moiety. The method further comprises controlling the lamp groups through the use of a controller utilizing data from FTIR sensors mounted in a fused quartz barrier which is permeable by infrared radiation but which seals the lamp arrays from the heating zones.

Abstract: An lightwave oven and method of cooking therewith for cooking food with radiant energy in the visible, near-visible and infrared ranges of the electromagnetic spectrum from a first plurality of high power lamps positioned above the food and a second plurality of high power lamps positioned below the food. The first plurality of lamps are sequentially operated at a first average power level by applying power thereto in a staggered manner so that not all of the first plurality of lamps are on at the same time, and the second plurality of lamps are sequentially operated at a second average power level by applying power thereto in a staggered manner so that not all of the second plurality of lamps are on at the same time. The stagger can be varied to change the time average power level of the first and/or second pluralities of lamps without adversely affecting the spectral outputs thereof. The first and second pluralities of lamps can be operated in one of several different modes.

Abstract: An apparatus for heat treating semiconductor wafers is disclosed. The apparatus includes a heating device which contains an assembly of light energy sources for emitting light energy onto a wafer. In particular, the light energy sources are positioned such that many different radial heating zones are created on a wafer being heated. The light energy sources form concentric rings. Tuning light sources are then placed in between the concentric rings of light.

Abstract: A heating assembly for heating semiconductor substrates includes a plurality of heating devices, with each heating device including an energy emitting filament adapted for electrically coupling to an external power supply and housed in a first enclosure. The first enclosure comprises energy transmitting material so that energy generated by the filament will be transmitted through the enclosure. A second enclosure houses the first enclosure, which also comprises energy transmitting material. The second enclosure is coated with a reflective layer and is housed in a third enclosure of transmitting material, which encapsulates the reflective coating so that when the energy emitting filament is energized, the reflective coating is contained in the heating device. A heating assembly includes a frame having a plurality of supports for supporting a plurality of the heating devices.

Abstract: An apparatus for heat treating semiconductor wafers is disclosed. The apparatus includes a heating device which contains an assembly of light energy sources for emitting light energy onto a wafer. In particular, the light energy sources are positioned such that many different radial heating zones are created on a wafer being heated. For instance, in one embodiment, the light energy sources form a spiral configuration. In an alternative embodiment, the light energy sources appear to be randomly dispersed with respect to each other so that no discernable pattern is present. In a third alternative embodiment of the present invention, the light energy sources form concentric rings. Tuning light sources are then placed in between the concentric rings of light.

Abstract: A preform (3) for use in making a container such as a bottle from a thermoplastic material is selectively heated prior to at least one step of blow molding or stretch-blow molding the heated preform. For this purpose, at least most (7A) of the radiation (4) transmitted generally towards the preform by a source (1A) is focused (8) onto a preferred area (A) thereof, the source is located substantially opposite the preferred area of the preform, whereby said the preferred area (A) receives most (7A) of the radiation (4) while the areas adjacent to the preferred area (A) do not receive the radiation fraction initially transmitted towards them by the source.

Abstract: An apparatus for producing a three-dimensional object by successive solidification of layers of a solidifiable material (7) at places corresponding to the respective cross-section of the object by means of radiation is provided whereby the apparatus comprises a support (4) for supporting the object (6) to be formed, a coating device (12) for applying layers of the solidifiable material (7) onto the support (4) or a previously solidified layer, a solidifying device (14) for solidifying the layers of the material (7) at places corresponding to the respective cross-section of the object and a heating apparatus (8) disposed above the support (4) in operational position for heating the solidifiable material (7), the heating apparatus (8) comprising at least one straight radiant heater (81) with a varying heating power along its length.

Abstract: A method and device for heating silicon carrier bodies in a deposition reactor are by means of radiated heat. In this method, the carrier bodies are irradiated by means of a heat radiation device which emits radiation having a color temperature of at least 2000.degree. C.

Abstract: An infrared conveyor furnace with controllable point source radiation elements incorporating a clean room internal environment. The conveyor transports moieties in an indexed manner through multiple heating zones heated by arrays of lamps. The lamps of each array are divided into a plurality of groups which are separately controlled to maintain a constant temperature across the surface of the moiety. The control of the lamp groups is accomplished through the use of a controller utilizing data from FTIR sensors mounted in a fused quartz barrier which is permeable by infrared radiation but which seals the lamp arrays from the heating zones.

Abstract: A heat-controlling device is provided with a transporting carriage for supporting and transporting a semiconductor substrate and a heating device having a plurality of heaters which apply heat in the width-wise direction of the heat-receiving member that is perpendicular to the transporting direction thereof and which are individually controlled by a controller. The controller only operates a set of the heaters that are adjacent the semiconductor substrate. Among the heaters being operated, those heaters, which are located at at least the leading end and the rear end in the transporting direction, have their outputs successively varied in accordance with the movement of the semiconductor substrate. Thus, it becomes possible to easily narrow the temperature distribution of the semiconductor substrate merely by controlling the output of the heaters.

Abstract: A secondary measurement of rapid thermal annealer temperature is provided. The secondary measurement allows a primary temperature measuring device to be monitored for proper operation in real time. A rapid thermal annealer system is provided having a heating chamber configured to receive and anneal a silicon wafer. Several halogen light sources are provided for heating the silicon wafer. An optical pyrometer measures temperature of the silicon wafer as it is heated by the halogen lamps. A thin silicon ring is provided with an s-type thermalcouple attached thereto. The silicon ring is positioned so that its inner edge is aligned closely with an outer edge of the silicon wafer. An s-type amplifier is connected to the s-type thermalcouple wherein the combination generates a signal indicative of the ring temperature. The ring temperature is compared against the wafer temperature as a measured by the pyrometer.

Abstract: A horizontal reactor for depositing an epitaxial layer on a semiconductor wafer. The reactor includes a reaction chamber sized and shaped for receiving the semiconductor wafer and a susceptor having an outer edge and a generally planar wafer receiving surface positioned in the reaction chamber for supporting the semiconductor wafer. In addition, the reactor includes a heating array positioned outside the reaction chamber including a plurality of heat lamps and a primary reflector for directing thermal radiation emitted by the heat lamps toward the susceptor to heat the semiconductor wafer and susceptor. Further, the reactor includes a secondary edge reflector having a specular surface positioned beside the heating array for recovering misdirected thermal radiation directed generally to a side of the heating array and away from the susceptor.

Abstract: A heater assembly for a vapor deposition apparatus is able to achieve extended operating life in the Oxygen rich low pressure high temperature atmosphere even though employing commercially available quartz lamps to generate heat. Multiple quartz lamps (1) are individually held in a socket-less support (3). The rigid lamp terminals (22 & 24) are connected to respective lengths of flexible stranded wire (30 & 28) by an INCONEL crimp insert (32 & 34), forming cables through which the lamp is connected in electrical circuit and that effectively isolate the lamp terminals from the physical effects of relative thermal expansion between heater assembly elements.

Abstract: A RTP system and method. A first lamp zone (108) is located around a periphery of a wafer (102) for heating the center of the wafer (102) and a second lamp zone (114) is located around the periphery of the wafer (102) for heating the edge of the wafer (102). The chamber (104) includes highly reflective surfaces (106). Light from the first and second lamp zones (108, 114) is reflected off of the highly reflective surfaces (106) at least three time before reaching the wafer (102). Thus, the wafer (102) is isotropically heated and uniform wafer heating is achieved.

Abstract: A heater assembly for supporting and energizing a plurality of heating lamps which includes a socket assembly which supports each of the lamps at a base portion thereof, provides power to effect energization of the lamps, and provides a directional flow of cooling fluid which is forced into close proximity to the base portions of the lamps to effect cooling of the base portions of each of the lamps. The cooling fluid is directed into a manifold disposed in the socket assembly in which each of the base portions of the lamps are disposed and is forced from the manifold through exit passageways disposed contiguous to the base portions of the lamps to force the cooling fluid into close proximity with the base portions of the lamps to efficiently cool the base portion of the lamp and assure long lamp life.

Abstract: A module for use in a heating appliance has a frame with first, second, third, and fourth sides. A first heating lamp is mounted substantially along the first side of the frame, a second heating lamp is mounted substantially along the second side of the frame, a third heating lamp mounted substantially along the third side of the frame, and an fourth heating lamp is mounted substantially along the fourth side of the frame. Fifth, sixth, seventh, and eighth heating lamps are mounted substantially diagonally to the frame. A first reflector reflects radiant energy from the first heating lamp, a second reflector reflects radiant energy from the second heating lamp, a third reflector reflects radiant energy from the third heating lamp, and a fourth reflector reflects radiant energy from the fourth heating lamp. A fifth reflector reflects radiant energy from the fifth, sixth, seventh, and eighth heating lamps.

Abstract: A CVD reactor includes a vacuum chamber having first and second thermal plates disposed therein and two independently-controlled multiple-zone heat sources disposed around the exterior thereof. The first heat source has three zones and the second heat source has two zones. A wafer to be processed is positioned below the first thermal plate and immediately above the second thermal plate, thereby being indirectly heated from above by the first heat source via the first thermal plate and indirectly heated from below by the first zone of the second heat source via the second thermal plate. A thermal ring plate which laterally surrounds the edge of the wafer absorbs heat energy emitted from the second zone of the second heat source and heats the outer edge of the wafer.

Abstract: A drying apparatus for use in a photosensitive material processing system, which is designed so that nonuniformity of drying in a direction intersecting a belt-shaped photosensitive material, e.g., a photographic negative film, photographic paper, etc., is eliminated, and the overall electric power capacity of the system is minimized. A plurality of electric current heaters (44.sub.1 and 44.sub.2) are disposed in parallel in a direction intersecting belt-shaped photosensitive materials (F.sub.1 and F.sub.2) transported, and each electric current heater is individually current-controlled to change the temperature distribution of the heated air, thereby compensating for the nonuniformity of drying of the belt-shaped photosensitive materials (F.sub.1 and F.sub.2) in the lateral direction, for example. The electric current heaters (44.sub.1 and 44.sub.2) are individually current-controlled by making the current input time different for each electric current heater.

Abstract: A method for compensating against wafer edge heat loss during rapid thermal processing includes a semiconductor wafer that is exposed to uniform radiant energy across the entire wafer surface. The wafer is exposed by projecting a radiant energy image onto the edge of said semiconductor wafer while providing radiant energy rays directly to the wafer's surface. The radiant energy image comprises reflecting radiant energy rays that pass through a positionally adjustable object onto the edge of the wafer. The positionally adjustable object is optional and is mounted between an optical lens and a radiant energy source or is mounted between a reflector and each radiant energy source (A second optical lens is optional). The energy rays absorbed at the edge of the wafer contain more heat intensity than do the rays which are absorbed by the inner portion of the wafer, thus producing uniform heat across the entire wafer.

Abstract: A method of selectively directing concentrated infrared energy onto thermoplastic articles to be welded to one another includes providing contoured elongated openings formed on energy reflecting shields. These shields directly conform to specific opposing surface areas on the thermoplastic articles to be joined by thermal welding to one another.

Abstract: A three zone rapid thermal processing system includes three arrays of radiant heating lamps for heating a semiconductor wafer. The arrays are positioned along the axis of the wafer such that one array is adjacent one face of the wafer, the second array is adjacent the second face of the wafer and the third array is adjacent the edge of the wafer. A wafer holder holds the wafer face transverse to the common axis of the radiant heating lamps. Reflectors at each array reflect radiant heat onto the wafer. The arrays are independently connected to power sources and a controller to provide efficient coupling of the heat sources and a uniform temperature distribution across a wafer.

Abstract: A system for controlling the temperature of a lamp annealer which system comprises a group of lamps for heating an article to be heated, a radiation thermometer for measuring the temperature of the article, and a lamp output conroller for controlling the output of the lamps based on the output of the thermometer, the controller having stored therein a target temperature control pattern.

Abstract: A core 6 is disposed inside of and spaced from a hollow plastic preform 1 subjected to external infrared radiation 4 including a first wavelength B.sub.1 that is absorbed by and heats the plastic, and a second wavelength B.sub.2 that propagates through the wall 2 of the preform. The propagated radiation 12 is converted into the first wavelength by the surface 7 of the core, and reemitted at 13 back towards the preform to heat its internal surface 8 to a higher temperature than its external surface 10. The preform may be axially rotated with the core stationary to implement uniform angular heating. Alternatively, the core may be irregularly configured and/or surface treated, with both the core and preform rotated in synchronism.

Abstract: A reflector array employs a number of linear, tubular heater lamps arranged in a circle concentric with the substrate to be heated. Some of the lamps have focusing reflectors and the remainder have dispersive reflectors. A peripheral cylindrical reflector surrounds the lamps and their associated reflectors. The combined reflectors permit balancing the thermal radiation intensity across the surface of the substrate.

Abstract: An apparatus for drying a moving web includes an elongate support frame, disposed transverse the web, and a number of heater modules releasably attached thereto. The heater modules each include a housing and an inner panel assembly releasably captured therein. An openable cover, in the housing, provides for ready insertion or removal of the inner panel assembly, which rests on two mutually perpendicular support members and is clamped against one of them by the closed cover. A number of heating elements are operatively supported on the inner panel assembly by means which include a locking member displaceable between a first position, whereat all of the heater elements are locked in position, and a second position, whereat the heater elements may be removed.

Abstract: A quartz infra-red radiator comprises a housing (1) and has disposed therein at least one heating element (2), electrical connections (3), plug connections (4, 5) on the back of the housing and with a heat-resistant insulating holder (6) for the heating element. In order to produce such a plug-in quartz infra-red radiator more easily and at a more competitive price, the heat-resistant insulating holder (6) comprises a space (7) to hold at least a part of a plug-in connection (5) and at least an aperture through which it is possible to pass a part of a plug connection (5) which is housed in the space (7) and which protrudes from the housing (1).

Abstract: A radiant heating device including a pair of concave surfaces for directing radiant energy toward an object positioned through an access opening in a receiving space therebetween with these concave surfaces extending to either side of this opening.

Abstract: The batch capacity of a barrel epitaxial reactor is improved by increasing the reaction chamber size and increasing the length of the radiant heat source so that a uniform temperature is maintained over a larger flat zone in the reaction chamber. Also, forced air flow from the blower of the reactor is distributed so that a positive air flow is maintained along the exterior wall of the reaction chamber and consequently the wall is maintained at a uniform cold temperature relative to the temperature of the reaction chamber.

Abstract: An apparatus for heat treating the surface of a body includes at least one infrared lamp carried on a stand. A circuit is provided for controlling the energization of the lamp. The circuit includes a parameter input mechanism for permitting an operator to input at least one operating parameter to the circuit. The circuit also includes a proportional control software responsive to a temperature of the body being heat treated and responsive to a parameter inputted by the input mechanism.

Abstract: A CVD reactor includes a vacuum chamber having first and second thermal plates disposed therein and two independently-controlled multiple-zone heat sources disposed around the exterior thereof. The first heat source has three zones and the second heat source has two zones. A wafer to be processed is positioned below the first thermal plate and immediately above the second thermal plate, thereby being indirectly heated from above by the first heat source via the first thermal plate and indirectly heated from below by the first zone of the second heat source via the second thermal plate. A thermal ring plate which laterally surrounds the edge of the wafer absorbs heat energy emitted from the second zone of the second heat source and heats the outer edge of the wafer.