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The earliest forms of DRAM mentioned above used [[bipolar transistors]]. While it offered improved performance over [[magnetic-core memory]], bipolar DRAM could not compete with the lower price of the then-dominant magnetic-core memory.<ref>{{cite web |title=1966: Semiconductor RAMs Serve High-speed Storage Needs |url=https://www.computerhistory.org/siliconengine/semiconductor-rams-serve-high-speed-storage-needs/ |website=Computer History Museum}}</ref> Capacitors had also been used for earlier memory schemes, such as the drum of the [[Atanasoff–Berry Computer]], the [[Williams tube]] and the [[Selectron tube]].
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In 1948, Bardeen and Brattain patented the progenitor of MOSFET, an insulated-gate FET (IGFET) with an inversion layer. The concept an inversion layer, forms the basis of DRAM technology today.<ref>{{cite book |author=Howard R. Duff |title=AIP Conference Proceedings |date=2001 |volume=550 |pages=3–32 |chapter=John Bardeen and transistor physics |doi=10.1063/1.1354371 |doi-access=free}}</ref>
In 1966, Dr. [[Robert Dennard]] invented modern DRAM architecture in which there's a single MOS transistor per capacitor,<ref name="ibm100">{{cite web |date=9 August 2017 |title=DRAM |url=https://www.ibm.com/ibm/history/ibm100/us/en/icons/dram/ |access-date=20 September 2019 |website=IBM100 |publisher=[[IBM]]}}</ref> at the [[IBM Thomas J. Watson Research Center]], while he was working on MOS memory and was trying to create an alternative to SRAM which required six MOS transistors for each [[bit]] of data. While examining the characteristics of MOS technology, he found it was capable of building capacitors, and that storing a charge or no charge on the MOS capacitor could represent the 1 and 0 of a bit, while the MOS transistor could control writing the charge to the capacitor. This led to his development of the single-transistor MOS DRAM memory cell.<ref>{{cite web |title=IBM100 — DRAM |url=https://www.ibm.com/ibm/history/ibm100/us/en/icons/dram/ |website=IBM |date=9 August 2017}}</ref> He filed a patent in 1967, and was granted U.S. patent number [https://web.archive.org/web/20151231134927/http://patft1.uspto.gov/netacgi/nph-Parser?patentnumber=3387286 3,387,286] in 1968.<ref>{{cite web |title=Robert Dennard |url=https://www.britannica.com/biography/Robert-Dennard |website=Encyclopedia Britannica|date=September 2023 }}</ref> MOS memory offered higher performance, was cheaper, and consumed less power, than magnetic-core memory.<ref name="computerhistory1970">{{cite web |title=1970: Semiconductors compete with magnetic cores |url=https://www.computerhistory.org/storageengine/semiconductors-compete-with-magnetic-cores/ |website=[[Computer History Museum]]}}</ref> The patent describes the invention: "Each cell is formed, in one embodiment, using a single field-efiiect transistor and a single capacitor."<ref>{{Cite patent|number=US3387286A|title=Field-effect transistor memory|gdate=1968-06-04|invent1=Dennard|inventor1-first=Robert H.|url=https://patents.google.com/patent/US3387286A}}</ref>
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