>I can't help thinking that if SiGe got to the point of being fast, cheap, AND easier to fab that AMCC could benefit significantly.
naturally, but do keep in mind that GaAs has had about twentysomething years of R&D; as i indicated, in comparison to GaAs, SiGe's still in grade school.
i'm no chip engineer and don't follow SiGe developments as often as i should (shall we invoke Gilder?), but at its core, i believe SiGe involves speeding circuit frequencies by adding small amounts of germanium to bipolar junction transistors. that's done during ultra-high-speed vacuum chemical vapor deposition about two-thirds of the way through the manufacturing process. and a critical issue is the amount of Ge added in the junction area, because as the amount increases, it becomes necessary to stay below a certain threshold (what's called the "Matthews and Blakely limit") or the device will become unstable.
IBM Microelectronics (http://www.research.ibm.com/sigetech), AMCC's foundry for SiGe, is doing lots of work in this area and might be a good resource for you. similarly, on the RF side, there's also a small ottawa-based fabless start-up called SiGe Microsystems (http://www.sige.com) that may intrigue you.
re: "fast, cheap AND easier to fab," i would most definitely add reliable as a criterion. i have yet to see any reliability data on SiGe; however, as i indicated, germanium is a problematic material in silicon and even more so as the basis for a heterojunction (e.g., subtle drift mechanisms that can occur in such devices). this is obviously a crucial requirement and many of these devices will require thousands of hours of high-temp accelerated testing to prove the stability of the materials.
western virginia, eh? well, technically, i'm not a dc resident, but a B&Mer (bridge & metro-er) just across the key bridge in arlington.
are you a united fan? i'll be there tomorrow.
a sweet & tender hooligan,
-chris. |
