Patent ID: 6095806
Filing Date: 2000-08-01
Classification: C23C,C30B,Y10S

Abstract:
A boat for holding a plurality of semiconductor wafers to be vertically stacked with gaps therebetween, said wafers having circular contours of substantially the same size, comprising:upper and lower frames arranged at upper and lower end portions, respectively, of said boat; andfirst, second and third support rods arranged between and connected to said upper and lower frames, said first, second and third support rods being arranged such that a port through which the wafers are transferred into and taken out of said boat is defined between said first and second support rods,wherein said first, second and third support rods are provided with a plurality of first racks vertically arrayed with gaps therebetween, a plurality of second racks vertically arrayed with gaps therebetween, and a plurality of third racks vertically arrayed with gaps therebetween, respectively, such that a plurality of horizontal wafer supporting levels are defined between said upper and lower frames by said racks, each wafer supporting level being defined by combination of first, second and third racks having corresponding height, andwherein said first and second racks are arranged substantially in symmetry with respect to an axis which is parallel to a transfer direction, in which the wafers are transferred into and out of said boat through said port, and passes through a center of said port, and said third rack is shifted from said axis by a certain distance.