Archived posting to the Leica Users Group, 2001/03/26
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]> Almost all the production CCDs have defective "dead" > pixels, and - sort of like cutting a diamond - Kodak > would cut up the wafer to produce the most efficient > mix of usable chips. I don't believe that's quite right. Wafers have a number of the 'dies' on a single wafer, typically in an XY grid pattern, like a checker board. Some of these individual dies typically do have defects. Each of the individual dies has what's called 'bond out pads', which are used to connect the wires between the die and the chip carrier (typically ceramic or plastic mounting holder that has the larger pins on it that goes into the ciruit board). The size of the individual die, is the size of the individual die...you do not get a larger usable array by, say, cutting the wafer such that four of the dies are together...they would have gaps bewteen the dies, and bonding to the pads between the dies would be most impossible, especially for an imaging sensor...you would have to cross over the image path. Also, you can't cut into the middle of a die, there is no place to bond out to then... I know it's quite technical, but I believe you relayed the story a little off kilter. - -------------------------------------------------------------------- Mail2Web - Check your email from the web at http://www.mail2web.com/ .