A Comparison of the Strength of Alumina Substrates for Different Separation Techniques

Carbon dioxide lasers arc widely used to separate alumina sheet into individual substrates for hybrid microcircuits. Laser separation offers several advantages over other conventional techniques; however, the effects on the flexural strength of the alumina have not previously been investigated. The flexural strength of alumina substratas separated by CO
2
, Q-switched YAG, and pulsed YAG lasers and diamond sewing are compared. The Q-switched YAG laser technique produced substrates 45 percent stronger than the CO
2
and pulsed YAG laser techniques, and 13 percent stronger than the diamond saw method.