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Why DRAM is so incompatible with general CMOS process?

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BarsMonster

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Could you please help me understand why you can't just create DRAM cells on CMOS chip?

Both capacitors & transistors are doable in general CMOS process, so DRAM should be doable too. Yes, there will be no fancy things like 'vertical' capacitors, but still should work.

Any ideas/links?
 

dhaval4987

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Let mme know if someone answers this question or you find out the answer.
 

dick_freebird

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You can do a DRAM in a standard MOS (or CMOS) process.
What you cannot do, is be cost competitive when you are
the only guy left not doing deep trench capacitors on a
same-sized wafer as your competition.

You "can" build a functioning DRAM using any kind of cap
you want. Whether you "should"....
 

BarsMonster

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But I guess it should be still smaller than SRAM cell, and hence I don't see why all these ARM's still use SRAM for internal memory...
 

ninju

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i'm not too familiar with mos fabrication process. i think all of the latest graphics cards come built in with around 2GB (minimum) of memory. Wouldn't DRAM be preferred for it?
 

BarsMonster

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i'm not too familiar with mos fabrication process. i think all of the latest graphics cards come built in with around 2GB (minimum) of memory. Wouldn't DRAM be preferred for it?
They all have external DRAM chips. Internally they have mere megabytes of SRAM.
 
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    ninju

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