Chip-on-CAPS (cable-patterned suspension)

A write frequency has been increasing by improvement of a write driver and a write head for higher transfer rate in hard disk drives. A certain method for high write frequency operation is to put a write driver chip on the suspension. We designed a chip-on-cable-patterned suspension (C-CAPS) that is an integrated wireless suspension with a write driver chip on. This paper describes the first observation of the effect on the chip-on-suspension in the write frequency and what type of the C-CAPS is suitable, especially relating to the location of a chip, for high performance hard disk drives. Next, we clarify characteristics of the C-CAPS, such as write current transition time, interface between the chip and disk, shock resistance, frequency response, thermal deformation due to temperature increase of the chip, and static attitude change due to bonding the chip. We conclude the C-CAPS contributes to increase a write frequency and the best location of a chip is on the tip of the load beam for high performance hard disk drives.