Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.csd.uwm.edu!cs.utexas.edu!rutgers!aramis.rutgers.edu!athos.rutgers.edu!nanotech From: doom@portia.stanford.edu (Joseph Brenner) Newsgroups: sci.nanotech Subject: Re: Simple nanomachines Keywords: nanotechnology Message-ID: Date: 31 Aug 89 21:34:00 GMT Sender: nanotech@athos.rutgers.edu Organization: Stanford University Lines: 34 Approved: nanotech@aramis.rutgers.edu >I suggest that some thought be devoted to the design of >simpler nanomachines, far simpler than an assembler. Good idea. >One such is a smart etchant. [...] >The result is a means of producing ICs with a simple, one-pass >process. Not so good, I think. As I remember it, the atomic density of Silicon is on the order of 10^22 atoms per square centimeter. Let's say we're going to make a chip that's about one square centimeter, and assume we need to do at least one operation on every atomic site in this area. How fast can we perform an operation? Does 10,000 times a second sound like a reasonable upper bound? Then, even if you allow 100,000 seconds to make the chip (that's over a day), we'd need 10^13 nanomanipulators to do the job. Now all you need to do is to figure out how we're going to manufacture over a trillion nanomanipulators without something like Drexler's self-replicating assemblers. It has been suggested that a Scanning Tunneling Microscope could be used to perform repairs on photolitho IC masks: maybe you could use some form of your dumb nanomanipulators to write very fine traces on some kind of template, which is then duplicated by some other means. -- Joe Brenner (J.JBRENNER@MACBETH.STANFORD.EDU Materials Science Dept/Stanford, CA 94305)