Abstract: An optical fiber preform suspending and supporting apparatus able to prevent deformation of a pin placed in a high temperature environment and able to support a porous optical fiber preform without adversely influencing supports of the pin and without causing inclination relative to the vertical line of a main shaft, wherein a movable connector is fitted into an enlarged-diameter portion of the lower end of a main shaft, this enlarged-diameter portion is connected with the movable connector by a pin so that the movable connector is able to swing around the pin, a holding portion including a supporting portion is formed integrally at the bottom of the movable connector to hold an enlarged-diameter portion of the upper end of a starting preform, and the diameter of the pin is in the range of 20% to 50% of the outside diameter of the enlarged-diameter portion of the lower end of the main shaft, and an optical fiber processing apparatus including the same.

Abstract: An assembly of heating furnace and semiconductor wafer-holding jig. This assembly includes a furnace body made of refractory or heat insulting material; a heater disposed around the inner side surface of the furnace body; a reaction chamber which forms a uniform heating zone; and a wafer-holding jig. The wafer-holding jig is capable of holding the wafer and advancing and retracting the wafer in the uniform heating region along the longitudinal direction of the furnace body. The front surface of the semiconductor wafer to be heat-treated is substantially in parallel with the surface of the heater. The assembly of the invention can be used in rapid thermal processing and the footprint of the heating furnace can be reduced.

Abstract: A vertical ceramic wafer boat for supporting a silicon wafer having a predetermined radius R. The wafer boat comprises a base and a pair of column racks. The column racks extend generally vertically upwards from the base. Each column rack includes at least one arm having an arcuate section. Each arcuate section is sized to provide substantial support for a 0.7 R boundary region of the wafer and spans an arc of less than 180 degrees.

Abstract: An apparatus for baking a wafer includes a heating plate for supporting the wafer to be baked, a lifting device for loading and unloading the wafer onto and from the upper surface of the heating plate, and a detector for detecting whether the wafer loaded by the lifting device onto the upper surface of the heating plate extends parallel to the upper surface, i.e., is situated correctly on the heating plate. The detector includes proximity sensors and a controller. The proximity sensors are disposed in or on the heating plate for sensing respective distances from the positions thereof to the wafer and generating signals indicative of whether the wafer is disposed more than a predetermined distance away from the sensors. The controller determines, on the basis of the signals generated by the proximity sensors, whether the baking process should be carried out and controls the baking process once it is initiated.

Abstract: A wafer (22) is placed on an upper surface of a holder body (23), and the holder body is inserted into a plurality of holder-aimed concave recesses (14) formed on supporters (12) accommodated in a heat treatment furnace such that the holder body is held horizontally. The holder body is formed into a disk shape free of recessed cut portions, and the holder body is formed with an upwardly projecting ring-like projection (24) extending in the circumferential direction of the holder body around the axis of the holder body. The wafer holder is constituted such that the wafer is placed on the holder body while contacting with the upper surface of the projection, and such that the outer diameter of the projection is formed to be in a range of 0.5D to 0.98D wherein D is the diameter of the wafer, so that the outer periphery of the wafer is kept from contacting with the projection. Occurrence of slips in the wafer is restricted by preventing warpage of the holder body upon fabricating the holder body.

Abstract: A firing setter, which is useful for a heat treatment or firing step upon production of ceramic-based electronic device components or production of metal-based components obtained by injection molding, is provided with plural trough-holes and has an alumina content of at least 70 wt. %. Each of the through-holes is linear with substantially the same inner diameter along a length thereof and has an inner diameter of from 0.3 to 1 mm. A process for producing the firing setter is also disclosed.

Abstract: A wafer treatment apparatus includes a wafer heating device having a wafer-load region at an upper portion, a shower head opposing the wafer-load region for ejecting/directing a source gas toward the wafer surface, and a reflecting apparatus positioned between the shower head and the heating device for reflecting thermal energy radiated from the heating device back toward the wafer-load region. The reflecting apparatus includes a reflector positioned above and opposing the wafer-load region, and a supporter for supporting the reflector. The reflector may have a flattened reflecting surface facing toward the wafer-load region, or may be a semi-spherical type reflector having a concave mirror facing toward the wafer-load region. The reflector can be controlled to move vertically relative to the wafer.

Abstract: A silicon tower or boat for removably supporting a plurality of silicon wafers during thermal processing. A preferred embodiment of the tower includes four legs secured on their ends to two bases. A plurality of slots are cut in the legs allowing slidable insertion of the wafers and support for them. The legs preferably have a rounded wedge shape with a curved front surface of small radius cut with the slots and a back surface that is either flat or curved with a substantially larger radius. Preferably, the legs are machined from virgin polysilicon formed by chemical vapor deposition from silane. The bases may be either virgin poly or monocrystalline silicon and be either integral or composed of multiple parts. Virgin polysilicon is preferably annealed to above 1025° C. before machining. Silicon parts may be joined by applying a spin-on glass between the parts and annealing the assembly. After assembly, the surface of a tower is subjected to sub-surface working.

Abstract: An apparatus is provided wherein a substrate is mechanically clamped to a heater block of a die bonder to hold down the heated substrate before and during the die bonding operation, thereby preventing warpage of the substrate. Embodiments include a clamp comprising a plurality of spring-loaded rollers which push down opposing outer edges of the substrate onto the heater block while the substrate is being heated and die bonded. The clamp minimizes warpage of the substrate by pushing the substrate flat onto the heater block, and allows the substrate to be moved into and away from the die bonding area.

Abstract: A ceramic heater (1) includes a ceramic substrate (2) having a heating surface (2a) for supporting and heating an object to be processed, a heating element (6) provided in the substrate (2), and embossed portions (4) on the heating surface (2a) which are to contacted with the objects. The number of the embossed portions (4) per unit area on the heat spot (3) is less than that on the rest of the heating surface (2a). When the average temperature of the heating surface (2a) is raised to reach a target temperature, the heat spot (3) having relatively high surface temperatures exist on the heating surface (2a).

Abstract: An apparatus for baking a wafer includes a heating plate for supporting the wafer to be baked, a lifting device for loading and unloading the wafer onto and from the upper surface of the heating plate, and a detector for detecting whether the wafer loaded by the lifting device onto the upper surface of the heating plate extends parallel to the upper surface, i.e., is situated correctly on the heating plate. The detector includes proximity sensors and a controller. The proximity sensors are disposed in or on the heating plate for sensing respective distances from the positions thereof to the wafer and generating signals indicative of whether the wafer is disposed more than a predetermined distance away from the sensors. The controller determines, on the basis of the signals generated by the proximity sensors, whether the baking process should be carried out and controls the baking process once it is initiated.

Abstract: A semiconductor wafer boat has a plurality of discrete boat parts stacked one atop the other. Each of the of the boat parts includes a wafer support in the form of a plurality of columns each having a plurality of vertically spaced apart grooves for use in supporting semiconductor wafers as vertically spaced from one another. Corresponding ones of the grooves in the columns of a boat part can receive the outer peripheral edge of the wafer directly, or a ring plate to which the wafer is mounted. Each adjacent pair of boat parts has confronting end portions forming a joint at which the boat parts of the pair are freely coupled to one another such that each of the boat parts may be replaced independently of the other boat parts. Thus, when any of the boat parts experiences thermal deformation after long periods of use, the boat part may be readily replaced without damaging any part of the boat and without the costs associated with replacing the boat entirely.

Abstract: A wafer treatment apparatus includes a wafer heating device having a wafer-load region at an upper portion, a shower head opposing the wafer-load region for ejecting/directing a source gas toward the wafer surface, and a reflecting apparatus positioned between the shower head and the heating device for reflecting thermal energy radiated from the heating device back toward the wafer-load region. The reflecting apparatus includes a reflector positioned above and opposing the wafer-load region, and a supporter for supporting the reflector. The reflector may have a flattened reflecting surface facing toward the wafer-load region, or may be a semi-spherical type reflector having a concave mirror facing toward the wafer-load region. The reflector can be controlled to move vertically relative to the wafer.

Abstract: An apparatus for semiconductor processing includes: a) at least one support member comprising an upper surface for supporting a semiconductor wafer; b) a component through which the support member extends, the component comprising a front surface and a back surface, at least one of the support member and the component being movable relative to the other of the support member and the component such that the support member can support a wafer in an elevated position above the front surface and can be withdrawn into the component to lower the wafer relative to the front surface of the component; and c) a block joined to the support member below the component back surface, the block engaging the component back surface when the support member upper surface extends above the component to a predetermined distance, the block preventing the support member upper surface from extending beyond the front surface by more than the predetermined distance.

Abstract: Boat comprising a number of vertically extending rods for the accepting therein of shield rings. Each shield ring is provided with a number of projections or other carrying means for accepting a wafer. The ‘thickness’ of the shield rings in the radial direction is not constant according to the invention and is smaller close to one of the rods than in the area between two rods.

Abstract: A substrate support, such as an edge ring, includes an inner portion, and an outer portion contiguous with the inner portion and extending radially outward therefrom. The inner portion has a raised annular extension forming a ridge for supporting a substrate.

Abstract: A novel apparatus and method of making the apparatus for supporting a substrate during processing. A base defining grooves at a substrate support location is described. Grooves are provided to catch wear particles from the substrate caused by friction during relative movement between the substrate and the support. A plurality of substrate support locations can be provided on the base surface. The base surface preferably comprises an annulus with substrate support locations spaced circumferentially around the annulus. Protrusions may be provided at substrate support locations. The protrusions define contact surfaces on which grooves can be formed.

Abstract: A furnace is provided generally including an upper heating chamber and a lower work base or firing platform. The upper chamber provides the main source of heat to the materials to be heat-treated. The upper chamber contains a muffle within which is located a heater ring assembly. The heater ring assembly is located in the middle to upper half of the muffle and includes an annular heating element that is located between an outer insulation ring and an inner quartz sleeve. A cavity or channel extends through the muffle into which insulation materials and the heater ring assembly is located. The channel area in the muffle below the heater ring assembly allows for the placement of the firing platform therein. The firing platform includes insulation material and a heating element located in the upper portion thereof.

Abstract: A substrate heater having a chamber, a heating element located in the chamber, and an elevator having a substrate holder. The holder can hold a plurality of planar substrates in a general spaced stacked configuration. The holder can be moved to allow substrates to be inserted and removed from various locations on the holder. In one embodiment the substrates are located very close to each other to accelerate the rate of heat transfer to newly inserted substrates. In another embodiment, the holder has an individual horizontal heater on the elevator for each substrate.

Abstract: A clamp holds a semiconductor wafer during an Al reflow process. The clamp is made of a ceramic material, and thereby clamp surface roughening which damages semiconductor wafers and other damaging of the wafer caused by the deformation of the clamp are avoided. A sloped surface of the clamp pad can also reduce the damage on the wafer by reducing the contact area between the clamp pad and the wafer. In addition, the clamp has several features that can reduce heat dissipation from the wafer to outside during the Al reflow. Slots formed on the pad reduce the amount of heat conduction through the clamp, and the polished inner surface of the clamp cap reflects the heat radiated from the wafer back to the wafer.

Abstract: A kiln tool uses a fiber-composite material comprising a yarn aggregate in which yarn including at least a bundle of carbon fibers and a carbon component other than carbon fibers is three-dimensionally combined and integrally formed so as not to separate from each other; and a matrix made of Si--SiC-based fiber filled between the yarn adjacent to each other within the yarn aggregate. The kiln tool has good workability and working accuracy, and excellent durability.

Abstract: A boat for semiconductor wafers has reduced contact surface area with the wafer, thereby preventing distortion of the wafer during heating. The boat has an upper member; a lower member, a plurality of wafers being loaded between the upper member and the lower member; and a plurality of support members vertically extended between and connecting the upper member to the lower member for supporting the wafers. A plurality of slots are successively and horizontally formed in each of the support members, and the peripheral edge of the wafer is inserted therein, wherein a hemisphere-shaped protrusion is formed inside the slot, and the bottom surface of the wafer contacts and is supported by each hemisphere-shaped protrusion at a single contact point.

Abstract: A boat for semiconductor wafers includes first, second and third support rods arranged between and connected to top and bottom plates. The first, second and third support rods include a plurality of first racks, a plurality of second racks, and a plurality of third racks, respectively, such that the racks of each rods are vertically arrayed with gaps therebetween. The first, second and third racks serving to define a plurality of horizontal wafer supporting levels. Each wafer supporting level is defined by only combination of the first, second and third racks of the corresponding height. In each wafer supporting level, the first and second racks are arranged substantially in symmetry with respect to an axis passing through the center of a wafer transfer port, and the third rack is arranged deviant from the axis by a certain distance corresponding to 5% to 48% of the diameter of the wafer.

Abstract: An heat-treating ring boat (20) for semiconductor wafers (W) has a top plate (21), a bottom plate (22), six columns (23-28), and 63 ring trays (31). The trays (31) are mounted in grooves (20a) of the columns (23-28). To fix the trays (31), a fixing rod (33) is detachably mounted between the top plate (21) and bottom plate (22). A through hole (21a) and a recessed portion (22a) to mount the fixing rod (33) therein are formed in the top plate (21) and bottom plate (22). Notches (34) to engage with the fixing rod (33) are formed in the trays (31). A notch (32) to engage with the fixing rod (33) is formed in the column (23). A projection (41) is formed on each tray (31) to abut against the side surface of the column (24).

Abstract: A substrate heat-treating apparatus includes a heat-treating plate, and support pins extending through the heat-treating plate to be vertically movable relative thereto. The support pins support each substrate at a lower surface thereof such that edges of the substrate are at a higher level than a central region of the substrate. This construction facilitates air flows into and out of a space between the lower surface of the substrate and the upper surface of the heat-treating plate when the substrate is vertically moved.

Abstract: A heat treatment boat houses a plurality of semiconductor wafers in a manner separated at intervals for heat-treating the wafers in a heat treatment furnace. The heat treatment boat includes a bottom plate, a first support rod erected on the outer peripheral edge of the bottom plate, a second support rod and a third support rod both erected on the bottom plate so as to make an central angle of 105.degree. to 120.degree. with the first support rod with respect to the center of the respective wafer supported by the rods, and a top plate provided opposed to the bottom plate for holding the rods. The stresses applied to the wafers housed in the heat treatment boat are distributed equivalently to three contacting points with the rods and become the minimum.

Abstract: A support for firing articles for a dental laboratory as described, in which a tensioning plate (14) is provided between two carrier plates (10, 12), the carrier plates (10, 12) and the tensioning plate (14) exhibiting a corresponding pattern of boreholes (16). In these boreholes (16) carrier pins (32) are introduced, which by displacement of the tensioning plate (14) with respect to the carrier plates (10, 12) are clamped in place and fixed in their position.

Abstract: The present invention is designed to provide an annealing method for silicon single crystal wafers, which makes it possible to increase the number of silicon single crystal wafers processed during a single annealing process under a variety of annealing performed on silicon single crystal wafers, such as oxygen outer diffusion annealing for forming a DZ layer, annealing that generates and controls BMD for providing IG functions, and annealing that endeavors to improve and enhance GOI characteristics by eliminating wafer surface layer COP, and internal grown-in defects, and also enables the suppression of dislocation and slip in elevated temperature annealing environments. It calls for annealing to be performed by stacking up around 10 wafers, treating this group as a unit, placing this group, either horizontally or slightly inclined at an angle of roughly 0.5.about.5.degree.

Abstract: The invention relates to a vertical rack for semiconductor wafer processing having strictly horizontally disposed arms wherein each arms has a rounded tip.

Abstract: An improved wafer boat for a vertical furnace has inner upper and lower corners formed as sloped surfaces, and has outer upper and lower corners formed as sloped surfaces. This prevents the formation and collection of particles off of the wafer boat that can generate a protrusion on the wafer boat. By preventing the formation of a protrusion, this improved wafer boat prevents damage to the wafers processed in the wafer boat and improves the reliability of semiconductor devices formed from those wafers. Also, holes are provided for locking pins on both the upper and lower plates of the wafer boat. This means that the wafer boat can be loaded into the furnace in both a rightside-up and upside-down orientation, thus increasing the lifespan of the boat and reducing boat maintenance costs.

Abstract: A vertical furnace for use in a semiconductor manufacturing apparatus, which comprises a heater, an outer tube, an inner tube, all being disposed concentrically in a multi-layered fashion, a boat adapted to be introduced into the inner tube with a wafer loaded thereon, and a boat cover disposed internally of the inner tube concentrically therewith. The boat cover is comprised of a boat cover body and an auxiliary cover plate connected to said boat cover body with a given gap therebetween, the boat cover body having a predetermined number of slit apertures extending in a generator direction thereof, the auxiliary cover plate being disposed to cover the slit apertures. The introduced reactive gas flows in branched streams, one flowing through the inside of the boat cover and the other flowing in past the boat cover, whereby the film deposited on the wafer is improved in uniformity and homogeneity.

Abstract: Vertical rack for supporting semiconductor wafers, the rack having either continuously upward angled arms or horizontal arms for providing near center support of the wafers.

Abstract: An annular-shaped edge ring support for a semiconductor wafer has an innermost radial portion for supporting the semiconductor wafer and an outermost radial portion contiguous with the inner portion. The inner portion has a graded thermal mass that generally increases with increasing radius.

Abstract: A rectangular spalling-resistant refractory setter for use in heating furnace, which is made of a material having a bending strength of 1,000 kgf/cm.sup.2 or higher at 1,000-1,300.degree. C. and which has slits extending from each of at least one pair of the parallel sides of the setter toward the opposite side in a length of 15-35% based on the length of each side which is parallel to the slit.A creep-resistant setter which is made of a Si--SiC sintered material containing controlled amounts of impurities and having a controlled porosity.An oxidation-resistant setter which is made of a Si--SiC sintered material containing controlled amounts of impurities and having a controlled porosity.These setters are superior in spalling resistance, creep resistance and oxidation resistance, can mount thereon an increased amount of materials to be fired, and give a higher firing efficiency.

Abstract: There is provided an improved kiln furniture assembly:wherein the improvement comprises vertical posts comprising:i) a vertically disposed channel, andii) a spacer block (13a) vertically separating the upper and lower horizontal beams which extend from the same post,wherein at least a portion of the spacer block or the horizontal beam is positioned within the vertically disposed channel.

Abstract: A vertical heat treating apparatus includes a first boat elevator for carrying a first wafer boat between a wafer transfer region and a predetermined position in a heat treating furnace, and a second boat elevator for carrying a second wafer boat between the wafer transfer region and the predetermined position in the heat treating furnace. With this construction, it is possible to eliminate the problems of causing the position shift of the wafer boat, so that and it is possible to prevent the wafer boat from overturning. The apparatus also has cutouts formed in the lower end portion of the wafer boat, and guide members formed on the upper surface of a wafer transfer stage so as to be engageable with the cutouts. With this construction, if the positioning is forcibly carried out when the wafer boat is loaded on the wafer transfer stage, it is possible to correct the position shift to prevent the shift from accumulating, so that it is possible to prevent the wafer boat from overturning.

Abstract: An apparatus for thermal treatment of a thin plate wafer having a peripheral edge, having a vacuum chamber, a heater block for heating the thin film wafer rigidly mounted and operatively positioned inside said vacuum chamber, a holding clamp positioned in said vacuum chamber and defining an open-ended cylinder having a bottom and a top, said bottom for receiving said heater block, said holding clamp for pressing against said wafer supported by said heater block; a device for holding the wafer in said open-ended cylinder to enable said holding clamp to hold the wafer prior to and subsequent to thermal treatment of the wafer, an elevator device for positioning said holding clamp relative to said heater block such that in use only said weight of said holding clamp presses against the wafer, and a mechanical device co-operating with the elevator device for supplying and removing wafers into and out of the apparatus.

Abstract: The invention relates to a structure for a firing table to accept ceramic items to be fired.

Abstract: A single furnace loading cycle technique and a ventable sintering box therefor are disclosed for the sintering of products, such as, ceramic substrates. The sintering box includes a closeable cover which is held open by collapsible or deformable or sensitive spacers in a first furnace temperature range. The sensitive spacers collapse or deform in a higher temperature range to seal closed the box and the substrates therein. Thus, volatile agents within the substrates are permitted to escape in the first temperature range but are prevented from escaping in the higher temperature range.Provision also is made using additional sensitive spacers for applying a weight upon the substrates when in the higher temperature range due to the collapse or deformation of the sensitive spacers.

Abstract: A tray for heat treatment furnace including a tray base which comprises a plate and a lattice part being fixed on the plate, said lattice part having a plurality of cylindrical reinforcements formed at cross portions thereof; a fixing device having a plurality of paired barrels being connected to each other by a plurality of connecting members, each of said paired barrels being provided with a plurality of cutting grooves on an upper surface thereof, one of the connecting members having a pair of coupling jaws for engagement with a portion of the lattice part; a plurality of spacers each being engageable with one of a respective said plurality of cutting grooves.

Abstract: A support assembly for supporting a glass panel during thermal processing. In one embodiment, a support assembly includes a base member, and a mechanism secured to the base member. The mechanism includes a support plate adapted for contact with a panel, wherein the mechanism is operative to distribute the weight of the panel and support plate about a bottom surface of the support plate. In a further embodiment a support assembly includes a base assembly and a leveling assembly having a plurality of plates defining a support surface. An alternative embodiment of a support assembly is adapted for supporting panels in a vertical position and includes a base assembly and a levelling assembly.

Abstract: A stacking system includes a frame having recesses therein used to partially define openings that permit gas generated during firing of a substrate within the space defined by the frame to escape without adversely affecting the substrate. A relatively thin tile placed on the frame provides the system with an additional level for substrates.

Abstract: A substrate holding assembly for horizontally holding a substrate to be treated is provided in a heat treatment chamber of a heat treatment apparatus. The substrate holding assembly has an annular base, and a plurality of fixed support projections provided on the annular base, for holding the underside of the substrate to be treated. A flexible beam portion is fixed to the annular base, or to a vertical support rod, and a flexible support projection is provided on the beam portion, for flexibly supporting a portion of the substrate to be treated which tends to flex downward under its own weight. Flexure caused by the own weight of the substrate to be treated held in the substrate holding assembly is thus corrected by the flexible holding portions. Accordingly, stresses caused in the substrates to be treated can be decreased or removed, and occurrence of slips in the substrate to be treated can be precluded in a high-temperature heat treatment. Accordingly, high yields can be obtained.

Abstract: A boat carrier for accommodating multiple width integrated circuit (IC) boats is provided. The boat carrier comprises a base member and opposed guide faces which abut side surfaces of IC boats of multiple widths. In a first embodiment, the boat carrier includes a first guide having a first guide face affixed to the base member, and a movable guide having a movable guide face releasably affixed to the base member. The movable guide face has a first position and a second position, whereby a narrower IC boat is receivable in the first position and a wider IC boat is receivable in the second position. In a further embodiment, the boat carrier comprises a base member, a fixed guide assembly having a fixed guide face, and an opposed guide assembly having an inner and outer guide face, whereby a boat having a first or second width is receivable.

Abstract: A thermal treatment boat having a plurality of annular, coaxial, spaced apart bands having substantially the same inner diameters. The bands are separated by a band spacing distance of from about 3.8 to 12.7 mm, each of the bands having a height, Height.sub.Band, in mm according to the equation: ##EQU1## wherein Height.sub.Band is always.gtoreq.wafer thickness; ColumnHeight is the total height of the treatment boat, mm; BandSpacing is the band spacing distance between adjacent bands, mm; and NumberBands is the total number of bands in the treatment boat. Preferably the NumberBands is from about 12 to about 100. Each band includes wafer support means for supporting a wafer therein at a position which is substantially centered between the upper edge surface and said lower edge surface thereof, the wafer support means in one embodiment including at least three inwardly extending projections.

Abstract: The invention pertains to a charging rack for firing objects composed of ceramic or glass ceramic materials in kiln, in particular a continuous kiln. The charging rack takes the form of a grate and comprises a frame and a number of bearing parts. The frame is made from a dispersion-hardened iron- or nickel-based alloy and bearing parts are made of the same dispersion-strengthened iron- or nickel-based alloy or from silicon carbide, an oxide ceramic material, a superalloy or a steel.

Abstract: Thermal treatment boat comprising a cylinder having a central axis and a plurality of band slots having opposed upper and lower surfaces in planes perpendicular to said central axis and spaced at predetermined locations along said central axis. At least one slot in each set extends around at least 180.degree. and less than of the full circumference of said cylinder. Pairs of adjacent band slots define an annular band therebetween. The height of each slot being from about 3.8 to 12.7 mm. Each of the bands having a height, Height.sub.Band, in mm, according to the equation: ##EQU1## wherein Height.sub.Band is always .ltoreq. wafer thickness; ColumnHeight is the total height of the cylinder, mm; BandSlotHeight is the height of the slot, mm; and NumberBands is the total number of bands in the treatment boat. The cylinder can include a wafer loading effector slot therethrough in a plane of the central axis extending along the length of the cylinder.

Abstract: A method of heat treating ceramic-based electronic components by providing a furnace fixture adapted to support the ceramic-based electronic components which is made from a substrate selected from the group consisting of silicon carbide (SiC), cordierite (2MgO.2Al2O.sub.3.5SiO.sub.2), mullite (3Al.sub.2 O.sub.3.2SiO.sub.2), stabilized zirconia, magnesium oxide (MgO) and alumina (Al.sub.2 O.sub.3) containing a glassy bond phase. A cladding layer of zirconia or magnesia is then deposited on the furnace fixture substrate by plasma deposition. The ceramic-based electronic component to be fired is placed on the zirconia-coated substrate; and heated to a desired temperature to heat treat the component.

Abstract: A heat treatment boat houses a plurality of semiconductor wafers in a manner separated at intervals for heat-treating the wafers in a heat treatment furnace. The heat treatment boat includes a bottom plate, a first support rod erected on the outer peripheral edge of the bottom plate, a second support rod and a third support rod both erected on the bottom plate so as to make an central angle of 105.degree. to 120.degree. with the first support rod with respect to the center of the respective wafer supported by the rods, and a top plate provided opposed to the bottom plate for holding the rods. The stresses applied to the wafers housed in the heat treatment boat are distributed equivalently to three contacting points with the rods and become the minimum.

Abstract: A firing underlying board having a long use life free from thermal expansion and which does not cause twisting of ribs, deformation of an end face, color change or cracking in a honeycomb structural body fired on the underlying board. The firing underlying board is composed mainly of 55-85 wt % of cordierite and 15-45 wt % of mullite. The firing underlying board is used to fire green ceramic honeycomb structural bodies placed thereon.