Abstract: A vertical diffusion furnace and a cap therefor are provided to minimize diffusion non-uniformity in a diffusion furnace caused by the positioning of a reaction gas outlet. In the vertical diffusion furnace, a reaction gas outlet is formed in the lower portion of a cap and adapted to extend downward through a flange. Thus, is provided a means to maintain diffusion uniformity in the diffusion furnace to comply with the necessity of processing large diameter wafers needed for highly integrated semiconductor devices. Thereby, a decrease in the rate of productivity for operating such equipment due to its positioning of a reaction gas outlet is prevented.

Abstract: A leakage gas detector for a semiconductor device includes a plurality of inflow apertures into which leakage gas flows. A detector sequentially detects the leakage gas in each of the inflow apertures via a plurality of valves, so as to leak test each of the plurality of inflow apertures for presence of possible leakage gas. Each of the plurality of valves are connected to corresponding of the plurality of inflow apertures to control the suction of the leakage gas into the detector. A controller selectively opens and closes each of the plurality of valves.

Abstract: A boat for a vertical diffusion furnace has an upper disk and a lower disk spaced parallel from each other by a predetermined distance. A pair of first bars, having a plurality of wafer holding slots, face each other along a first center plane extending along a diameter of the upper and lower disks, and connect the upper and lower disks. A pair of second bars also connect the upper and lower disks, and are positioned at a predetermined angle with respect to a second center plane orthogonal to the first center plane. The second bars have a plurality of slots corresponding to the slots of the first bars. A pair of first auxiliary bars are installed adjacent to the pair of first bars to also connect the upper and lower disks. The boat may further have a pair of second auxiliary bars for connecting the upper and lower disks at positions adjacent to the pair of second bars. Also, a pair of horizontal supporting bars connect the first auxiliary bars to the second auxiliary bars.