Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!uunet!aplcen!samsung!usc!rutgers!rochester!pt.cs.cmu.edu!MATHOM.GANDALF.CS.CMU.EDU!lindsay From: lindsay@MATHOM.GANDALF.CS.CMU.EDU (Donald Lindsay) Newsgroups: comp.arch Subject: Re: What's wrong with CRT storage? Message-ID: <10104@pt.cs.cmu.edu> Date: 3 Aug 90 21:01:37 GMT References: Organization: Carnegie-Mellon University, CS/RI Lines: 30 In article jsp@milton.u.washington.edu (Jeff Prothero) writes: >Why not use electron beams to >read/write nonrotating electric mass storage? >Has any work been done >on this since the 50s? Yes, there has been work on this in the last decade or so. >o Potential storage density higher than optical. > (We use scanning electron microscopes to see > features too small for optical microscopes.) Electron beams can indeed be small. However, the charge has to be stored. The last proposal I remember was going to fabricate capacitors onto a wafer. This differs from a DRAM in that the beam replaces some or all of the wiring pattern. Also, this is wafer- scale, of course. I'm not sure what happened. Perhaps the fabrication people refused to stop improving DRAM. Perhaps it was the bulk of the tube. Maybe it was the lack of parallelism - one beam means one bit wide, no? Or maybe the projects are still going on. I know that some things, like CCD memory, died in spite of being viable. ( CCD was intrinsically about twice as dense as DRAM, but a factor of two is just a one-year phase angle in this business.) -- Don D.C.Lindsay