Abstract:
Chemical vapor deposition processes utilize chemical precursors that allow for the deposition of thin films to be conducted at or near the mass transport limited regime. The processes have high deposition rates yet produce more uniform films, both compositionally and in thickness, than films prepared using conventional chemical precursors. In preferred embodiments, trisilane is employed to deposit thin films containing silicon useful in the semiconductor industry in various applications such as transistor gate electrodes.
Abstract:
One or more of three different measures are taken to preheat a wafer (44) before it is loaded into direct contact with a wafer holder (42), in order to provide optimal throughput while reducing the risk of thermal shock to the wafer (44). The first measure is to move the wafer holder (42) to a raised position prior to inserting the wafer (44) into the reaction chamber (20) and holding the wafer (44) above the wafer holder (42). The second measure is to provide an increased flow rate of a heat-conductive gas (such as Hs purge gas) through the chamber (20) prior to inserting the wafer (44) therein. The third measure is to provide a power bias to radiative heat elements (e.g., heat lamps) (51) above the reaction chamber (20).
Abstract:
One or more of three different measures are taken to preheat a wafer (44) before it is loaded into direct contact with a wafer holder (42), in order to provide optimal throughput while reducing the risk of thermal shock to the wafer (44). The first measure is to move the wafer holder (42) to a raised position prior to inserting the wafer (44) into the reaction chamber (20) and holding the wafer (44) above the wafer holder (42). The second measure is to provide an increased flow rate of a heat-conductive gas (such as Hs purge gas) through the chamber (20) prior to inserting the wafer (44) therein. The third measure is to provide a power bias to radiative heat elements (e.g., heat lamps) (51) above the reaction chamber (20).
Abstract:
Chemical vapor deposition processes utilize chemical precursors that allow for the deposition of thin films to be conducted at or near the mass transport limited regime. The processes have high deposition rates yet produce more uniform films, both compositionally and in thickness, than films prepared using conventional chemical precursors. In preferred embodiments, trisilane is employed to deposit thin films containing silicon useful in the semiconductor industry in various applications such as transistor gate electrodes.
Abstract:
An improved chemical vapor deposition reaction chamber having an internal support plate (40) to enable reduced pressure processing. The chamber has a vertical-lateral lenticular cross section with a wide horizontal dimension and a shorter vertical dimension between bi-convex upper and lower walls (12, 14). A central horizontal support plate (40) is provided between two lateral side rails (16, 18) of the chamber. A large rounded rectangular aperture is formed in the support plate for positioning a rotatable susceptor on which a wafer is placed. The shaft of the susceptor extends downward through the aperture and through a lower tube depending from the chamber. The support plate segregates the reaction chamber into an upper region and a lower region (66, 68), with purge gas being introduced through the lower tube into the lower region to prevent unwanted deposition therein. A temperature compensation ring is provided surrounding the susceptor and supported by fingers connected to the support plate. The temperature compensation ring may be circular or may be built out to conform to the rounded rectangular shape of the support plate aperture. The ring may extend farther downstream from the susceptor than upstream. A separate sacrificial quartz plate may be provided between the circular temperature compensation ring and the rounded rectangular aperture. The quartz plate may have a horizontal portion and a vertical lip in close abutment with the aperture to prevent devitrification of the support plate. A gas injector abuts an inlet flange of the chamber and injects process gas into the upper region and purge gas into the lower region. The gas injector includes a plurality of independently controlled channels disposed laterally across the chamber, the channels merging at an outlet of the injector to allow mixing of the adjacent longitudinal edges of the separate flows well before reaching the wafer.
Abstract:
One or more of three different measures are taken to preheat a wafer (44) before it is loaded into direct contact with a wafer holder (42), in order to provide optimal throughput while reducing the risk of thermal shock to the wafer (44). The first measure is to move the wafer holder (42) to a raised position prior to inserting the wafer (44) into the reaction chamber (20) and holding the wafer (44) above the wafer holder (42). The second measure is to provide an increased flow rate of a heat-conductive gas (such as Hs purge gas) through the chamber (20) prior to inserting the wafer (44) therein. The third measure is to provide a power bias to radiative heat elements (e.g., heat lamps) (51) above the reaction chamber (20).
Abstract:
A wafer support system comprising a segmented susceptor (602) having top and bottom sections and gas flow passages therethrough. A plurality of spacers or a spacer (615) projecting from a recess (604) formed in the top section (608) of the susceptor support a wafer (648) in spaced relationship with respect to the recess. A sweep gas is introduced to the bottom section (618) 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. Short purge channels may be provided to deliver some of the sweep gas to regions surrounding the spacers to cause a continuous flow of protective purge gas around the spacers. A common bottom section may cooperate with a plurality of different top sections to form segmented susceptors suitable for supporting various sized wafers.
Abstract:
A wafer support system comprising a segmented susceptor (602) having top and bottom sections and gas flow passages therethrough. A plurality of spacers or a spacer (615) projecting from a recess (604) formed in the top section (608) of the susceptor support a wafer (648) in spaced relationship with respect to the recess. A sweep gas is introduced to the bottom section (618) 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. Short purge channels may be provided to deliver some of the sweep gas to regions surrounding the spacers to cause a continuous flow of protective purge gas around the spacers. A common bottom section may cooperate with a plurality of different top sections to form segmented susceptors suitable for supporting various sized wafers.