It's that time of the month to re-examine the KM+MR road map.
Somebody on the QNTM board posted the most recent road map that QNTM is providing re: their heads biz which is parallel to Read Rite's MR biz:
techstocks.com
"...ú heads will shows signs of turnaround soon
ú QNTM is very confident in their heads business - they should be able to keep pace with the areal density numbers that RDRT estimates
ú Mid '97 2.1Gb/platter MR
ú Mid '98 2.8Gb/platter MR
ú Mid '99 4.2Gb/platter Spin Valve
ú Mid '00 7.0Gb/platter Giant MR
ú anticipate never more than 1/3 internal supply
ú QNTM believes that the technological advantage is still the best reason to continue in heads business...."
Note that 5.0 Gbits/in2 is roughly equal to 7.0 Gbytes/platter.
Now, we know that KM works with the older inductive heads and at least 2 kinds of proximity recording heads (see 1996 2nd quarter 10Q). We also know that U of Minn. MINT, Velocidata, Maxtor, WDC, HMTT and probably Read Rite, among others, have publicly indicated that they have done work with KM.
As far as MR is concerned, AXC has publicly stated that it is working on KM+MR in the lab. The most recent job postings related to KM R&D positions provide a clue, I suppose, to the ramp-up in the effort. A head manufacturer and another drive maker are also working on KM+MR in their respective labs.
Within this context, I think it is signifcant that Dr. Judy and his crew at the Univ. of Minn. MINT have proposed a research project to investigate the use of a variation of KM in 5 Gbit/in2 and beyond recording, or 7 Gbytes/platter and beyond...
ee.umn.edu
6.Soft Keeper to Prevent Thermally-Activated Decay of Recording in Longitudinal Thin Film Media (Jack Judy, John Sivertsen, MINT, TEL: 612-625-7381)
As areal storage densities of longitudinal magnetic recording media is increased beyond 5 Gigabit/in2, it is proposed to use a multilayer overlayer of a magnetic sendust keeper to prevent decay of the remanent magnetizations of UHDR recorded bits through thermally-activated magnetic after-effect-induced switching of magnetic domains clusters. Keepered longitudinal media exhibits increased signal output, decreased isolated pulse widths, pulse shape and amplitude asymmetry, and increased bit-shift margins.
In assessing the above project, some of you may find it useful to refer back to J.Chen's description of his work on KM and MR/GMR in his resume at...
ee.umn.edu:80/users/jchen/research/projects.html
As for FC heads. We only have the skimpiest of information in this area. The Velocidata paper did mention that its Toroidal TFI Heads would work best with variable reluctance recording, or KM, but the paper was also theoretical in nature. It is entirely possible that Ampex has their own complementary FC head program that exploits the similar magnetic confinement field phenomenon that I'm guessing that Velocidata is using. Or Velocidata and Ampex may indeed be working
together. We should know more in the days and weeks to come. I am actually hoping that Terastor's unabashed grab for mind share with their magneto-optical device will prod Ampex to release some more facts from its tightly shut purse.
That's it for now. Remember that if you come across a MR magnetics expert who tells you that KM is off-tangent to MR Recording you can
now point out the following facts:
1) A specialized inductive head is used to provide the write functions in MR Recording. The Toroheads or the FC heads MAY represent a low-cost advance of inductive head technology. When used with KM, Toroheads or FC heads MAY represent a low-cost way of extending inductive recording.
2) KM does provide benefits other than just low-cost extra-capacity.
There are at least 4 groups of magnetic pros working along similar if not different paths to investigate the applicability of those benefits to future versions of MR.
Let me end on this note. Western Digital was the only drive maker to gain market share last year. Everybody else lost a few points, including beleaguered Maxtor. Last week, Seagate indicated that it was prepared to regain the market share it lost last year. Quantum's head biz is, I think, showing better yields and they may also be in a position to regain market share. Western Digital is obviously ready to meet those challenges as well as stake out new territory in the enterprise and laptop segment. Given all those atmospherics and setting aside whatever technical issues may be remaining re: KM, can Maxtor really afford not to have that price/capacity advantage that KM provides during the crucial 4th quarter? |
