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benny16
Joined: 01 Mar 2004
Posts: 36
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 13 Jul 2004 5:39 Metal Mask ROM |
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Hi, do anyone know where i can find more information of "metal mask rom cell arrary" ?
Thanks
Benny
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jaxshai
Joined: 22 Jun 2004
Posts: 49
Helped: 1
Location: Shanghai
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| 23 Jul 2004 4:25 Metal Mask ROM |
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metal mask rom is very different from the conventional mask rom concept.
It is formed by the selectable vias,not the VT imp to the mos transistors in conventinal mask rom
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benny16
Joined: 01 Mar 2004
Posts: 36
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| 23 Jul 2004 7:39 Re: Metal Mask ROM |
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Hi, where i can find more related information ?
Thanks
Benny
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sunny656
Joined: 25 May 2004
Posts: 34
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| 29 Jul 2004 4:01 Re: Metal Mask ROM |
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| The 2nd edition of Berkeley ICbook: Digital Integrated Circuit.
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laneliu332
Joined: 31 Jul 2004
Posts: 3
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| 31 Jul 2004 15:18 Re: Metal Mask ROM |
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| use this kind of rom,it is very easy to reverse it,and its area is larger because of contact via
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sunny656
Joined: 25 May 2004
Posts: 34
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| 03 Aug 2004 5:17 Re: Metal Mask ROM |
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Hi,
What are the main physical features of MMR ?
sunny656
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sunny656
Joined: 25 May 2004
Posts: 34
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| 03 Aug 2004 6:00 Re: Metal Mask ROM |
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Hi,
I've an ambiguity about MMR. Some IC book says that MMR is programmed using contact mask layer only. Some other IC book says that MMR is programmed using metal-1 layer only. Which programming methodology is true to MMR ?
sunny656
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kaven
Joined: 11 Jul 2002
Posts: 13
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| 01 Sep 2004 6:55 Re: Metal Mask ROM |
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For serial rom ( implant code ), all the non-selected gates are active ( on ) and the selected gate is off, once the gate is coded, it will be on, no matter the gate voltage.
In same condition but replace the ion-implantation by a metal which short the source and Drain of selected gate can also get same result and the code could be metal, via or contact depends on design, basically we will use the last mask layer to reduce the production lead time
Anyway, compare to implant code, the area of metal code is much larger ( source / drain contact rule )
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kaven
Joined: 11 Jul 2002
Posts: 13
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| 01 Sep 2004 6:55 Re: Metal Mask ROM |
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For serial rom ( implant code ), all the non-selected gates are active ( on ) and the selected gate is off, once the gate is coded, it will be on, no matter the gate voltage.
In same condition but replace the ion-implantation by a metal which short the source and Drain of selected gate can also get same result and the code could be metal, via or contact depends on design, basically we will use the last mask layer to reduce the production lead time
Anyway, compare to implant code, the area of metal code is much larger ( source / drain contact rule )
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