Hi Z;
<<I understand that the testing of heads has become far more complex and that they are now graded by arial density capability similar to processors where the best go into the leading edge density drives. Is this a new development? If so, then a one time increase leading edge arial density has taken place which may mean the recent increase has been overstated. >>
I am not sure I catch the gist of the above statement. But the question you asked leading up to this one suggests an assumption that GMR is one homogenous specification and that makers sort out through testing which of these go where which isn't the case. However, if you are making heads for internal SEG use, and the designers have managed to tailor several products based on one platform, then it is possible to sort heads according to some (or several) attributes, mostly electrical, such as signal-to-noise ratio, for different programs. In general, this likely is not as easy for independent suppliers such as SAE and Read-Rite where qualification is by program(product) and strict adherence to specifications is required. The idea there would be to get qualified on a family or products where sorting might open the yield window. But keep in mind that in both cases, volumes have to match requirements.
Technical requirements on suspensions, like the attributes of all components, have been steadily more difficult. Geometry specs (especially related to pitch & roll) get tighter and tighter. Now of course, in the case of circuit-on-suspension types, there are electrical tests to perform, and a new emerging requirement is related to resonance (or rather the suspensions resilience to being excited into a resonant state by an outside inducement). It isn't the same old product as in the days when the suspension was not much more then a load beam for the head and the wires. In some ways you could argue that technology has been migrating to the suspension. This is an especially accurate observation when you consider microactuation.
Best,
Stitch |
