| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem that burrs, chips, etc., are formed and an outward appearance defect is generated when a ceramic substrate is parted into individual wiring boards. SOLUTION: When one ceramic substrate 7 are cut and parted along parting grooves 6 to form many wiring boards 9, plural cavities 5 are formed vertically side by side in areas of the ceramic substrate 7 right below the parting grooves 6, within a range defined by 0.24×(t-c1-c2)<=nd<=0.38×(t-c1-c2) and d<=0.62×1+log(c1/w)} (t: thickness (mm) of insulating base body, c1: depth (mm) of parting groove on cutting start point side, c2: depth (mm) of parting groove on cutting end-point side, w: maximum opening width (mm) of parting groove, n: number of cavities, d: vertical internal diameter (mm) of each cavity part). |
