Editing Dynamic random-access memory (section)

=== Single MOS DRAM ===
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-effect 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> 

MOS DRAM chips were commercialized in 1969 by Advanced Memory Systems, Inc of [[Sunnyvale, California|Sunnyvale, CA]]. This 1024 bit chip was sold to [[Honeywell]], [[Raytheon]], [[Wang Laboratories]], and others.
The same year, Honeywell asked [[Intel]] to make a DRAM using a three-transistor cell that they had developed. This became the Intel 1102 in early 1970.<ref>{{cite web|url=http://inventors.about.com/library/weekly/aa100898.htm|archive-url=https://archive.today/20130306105823/http://inventors.about.com/library/weekly/aa100898.htm|url-status=dead|archive-date=March 6, 2013|title=Who Invented the Intel 1103 DRAM Chip?|publisher=ThoughtCo|author=Mary Bellis|date=23 Feb 2018|access-date=27 Feb 2018}}</ref> However, the 1102 had many problems, prompting Intel to begin work on their own improved design, in secrecy to avoid conflict with Honeywell. This became the first commercially available DRAM, the [[Intel 1103]], in October 1970, despite initial problems with low yield until the fifth revision of the [[photomask|mask]]s. The 1103 was designed by Joel Karp and laid out by Pat Earhart. The masks were cut by Barbara Maness and Judy Garcia.<ref>{{cite web |url=http://archive.computerhistory.org/resources/still-image/PENDING/X3665.2007/Semi_SIG/Notes%20from%20interview%20with%20John%20Reed.pdf |title=Archived copy |access-date=2014-01-15 |url-status=dead |archive-url=https://web.archive.org/web/20140116124021/http://archive.computerhistory.org/resources/still-image/PENDING/X3665.2007/Semi_SIG/Notes%20from%20interview%20with%20John%20Reed.pdf |archive-date=2014-01-16 }}</ref>{{original research inline|date=December 2016}} MOS memory overtook magnetic-core memory as the dominant memory technology in the early 1970s.<ref name="computerhistory1970"/>

The first DRAM with multiplexed row and column [[address bus|address lines]] was the [[Mostek]] MK4096 4&nbsp;Kbit DRAM designed by Robert Proebsting and introduced in 1973. This addressing scheme uses the same address pins to receive the low half and the high half of the address of the memory cell being referenced, switching between the two halves on alternating bus cycles. This was a radical advance, effectively halving the number of address lines required, which enabled it to fit into packages with fewer pins, a cost advantage that grew with every jump in memory size. The MK4096 proved to be a very robust design for customer applications. At the 16&nbsp;Kbit density, the cost advantage increased; the 16&nbsp;Kbit Mostek MK4116 DRAM,<ref>{{cite web |first=Ken |last=Shirriff |title=Reverse-engineering the classic MK4116 16-kilobit DRAM chip  |date=November 2020 |url=http://www.righto.com/2020/11/reverse-engineering-classic-mk4116-16.html}}</ref><ref>{{cite web |first=Robert |last=Proebsting |interviewer=Hendrie, Gardner |title=Oral History of Robert Proebsting |date=14 September 2005 |publisher=Computer History Museum |id=X3274.2006 |url=https://www.cs.utexas.edu/~hunt/class/2016-spring/cs350c/documents/Robert-Proebsting.pdf}}</ref> introduced in 1976, achieved greater than 75% worldwide DRAM market share. However, as density increased to 64&nbsp;Kbit in the early 1980s, Mostek and other US manufacturers were overtaken by Japanese DRAM manufacturers, which dominated the US and worldwide markets during the 1980s and 1990s.

Early in 1985, [[Gordon Moore]] decided to withdraw Intel from producing DRAM.<ref>{{cite web |url=http://www.shmj.or.jp/makimoto/en/pdf/makimoto_E_01_12.pdf |title=Outbreak of Japan-US Semiconductor War |archive-url=https://web.archive.org/web/20200229223250/http://www.shmj.or.jp/makimoto/en/pdf/makimoto_E_01_12.pdf |archive-date=2020-02-29 }}</ref>
By 1986, many, but not all, United States chip makers had stopped making DRAMs.<ref>{{cite book |first1=William R. |last1=Nester |title=American Industrial Policy: Free or Managed Markets? |url=https://books.google.com/books?id=hCi_DAAAQBAJ |date=2016 |publisher=Springer |isbn=978-1-349-25568-9 |page=115}}
</ref>  Micron Technology and Texas Instruments continued to produce them commercially, and IBM produced them for internal use. 

In 1985, when 64K DRAM memory chips were the most common memory chips used in computers, and when more than 60 percent of those chips were produced by Japanese companies, semiconductor makers in the United States accused Japanese companies of [[export dumping]] for the purpose of driving makers in the United States out of the commodity memory chip business. Prices for the 64K product plummeted to as low as 35 cents apiece from $3.50 within 18 months, with disastrous financial consequences for some U.S. firms.  On 4 December 1985 the US Commerce Department's International Trade Administration ruled in favor of the complaint.<ref>
{{cite news |first1=David E. |last1=Sanger
|url=https://www.nytimes.com/1985/08/03/business/japan-chip-dumping-is-found.html |title=Japan chip 'dumping' is found 
|newspaper=New York Times
|date=3 August 1985}}
</ref><ref>
{{cite news |first1=Donald |last1=Woutat.
|url=https://www.latimes.com/archives/la-xpm-1985-12-04-fi-625-story.html |title=6 Japan Chip Makers Cited for Dumping
|newspaper=Los Angeles Times
|date=4 November 1985}}
</ref><ref>
{{cite news |url=https://www.latimes.com/archives/la-xpm-1986-03-14-fi-20761-story.html |title=More Japan Firms Accused: U.S. Contends 5 Companies Dumped Chips
|newspaper=Los Angeles Times
|date=1986}}
</ref><ref>
{{cite news |first1=David E. |last1=Sanger
|url=https://www.nytimes.com/1987/11/03/business/japanese-chip-dumping-has-ended-us-finds.html |title=Japanese Chip Dumping Has Ended, U.S. Finds
|newspaper=New York Times
|date=3 November 1987}}
</ref>

[[Synchronous dynamic random-access memory]] (SDRAM) was developed by [[Samsung]]. The first commercial SDRAM chip was the Samsung KM48SL2000, which had a capacity of 16{{nbsp}}[[Mebibit|Mb]],<ref name="electronic-design">{{cite journal |title=Electronic Design |journal=[[Electronic Design]] |date=1993 |volume=41 |issue=15–21 |url=https://books.google.com/books?id=QmpJAQAAIAAJ |publisher=Hayden Publishing Company |quote=The first commercial synchronous DRAM, the Samsung 16-Mbit KM48SL2000, employs a single-bank architecture that lets system designers easily transition from asynchronous to synchronous systems.}}</ref> and was introduced in 1992.<ref>{{cite web |title=KM48SL2000-7 Datasheet |url=https://www.datasheetarchive.com/KM48SL2000-7-datasheet.html |publisher=[[Samsung]] |access-date=19 June 2019 |date=August 1992}}</ref> The first commercial [[DDR SDRAM]] ([[double data rate]] SDRAM) memory chip was Samsung's 64{{nbsp}}Mb DDR SDRAM chip, released in 1998.<ref>{{cite news |title=Samsung Electronics Develops First 128Mb SDRAM with DDR/SDR Manufacturing Option |url=https://www.samsung.com/semiconductor/insights/news-events/samsung-electronics-develops-first-128mb-sdram-with-ddr-sdr-manufacturing-option/ |access-date=23 June 2019 |work=[[Samsung Electronics]] |publisher=[[Samsung]] |date=10 February 1999}}</ref>

Later, in 2001, Japanese DRAM makers accused Korean DRAM manufacturers of dumping.<ref>
{{cite web |author1=Kuriko Miyake
|url=http://edition.cnn.com/2001/TECH/industry/10/25/chip.dumping.idg/ |title=Japanese chip makers say they suspect dumping by Korean firms |publisher=CNN
|date=2001}}
</ref><ref>
{{cite news |url=https://www.itworld.com/article/2794396/japanese-chip-makers-suspect-dumping-by-korean-firms.html |title=Japanese chip makers suspect dumping by Korean firms |newspaper=ITWorld
|date=2001}}
</ref><ref>
{{cite web |url=https://www.eetimes.com/dram-pricing-investigation-in-japan-targets-hynix-samsung/ |title=DRAM pricing investigation in Japan targets Hynix, Samsung
|date=2001 |publisher=EETimes }}
</ref><ref>
{{cite web |url=https://phys.org/news/2006-01-korean-dram-japan.html |title=Korean DRAM finds itself shut out of Japan |publisher=Phys.org
|date=2006 }}
</ref>

In 2002, US computer makers made claims of [[DRAM price fixing]].