CERAMIC BASE HAVING DIVISION GROOVES AND RESISTOR USING THE SAME

摘要

PROBLEM TO BE SOLVED: To prevent occurrence of a crack from a corner part by a method wherein a through hole is formed in a rectangular shape in plane and the radius of curvature of the corner part shaped like a curved surface or the width thereof shaped like a C surface is made to be in a specified range. SOLUTION: A ceramic base 10 has a plurality of longitudinal and lateral division grooves 11 in the surface and a plurality of through holes 12 are formed in these division grooves 11. The shape of the through hole 12 is rectangular in plane and the four corners 14 thereof are shaped like curved surfaces having the radius R of curvature. Therefore occurrence of a crack from the corner part can be prevented. This radius R of curvature is made to be in the range of 1/10-1/3 to a length A of a short side of the through hole 12. The corner part 14 is shaped like a C surface in another way, and therefore the wear of a pin for forming the through hole 12 can be prevented, while the occurrence of the crack from the corner part 14 can be prevented. The width of the part shaped like the C surface is made to be in the range of 1/8-1/3 to the length A of the short side of the through hole 12.