Editing Wafer (electronics) (section)

==== Silicon substrate ====
Silicon wafers are available in a variety of diameters from 25.4&nbsp;mm (1&nbsp;inch) to 300&nbsp;mm (11.8&nbsp;inches).<ref name=f450c>{{cite web|title = Evolution Of Silicon Wafer {{!}} F450C|url = http://www.f450c.org/infographic/|archive-url = https://archive.today/20160105165200/http://www.f450c.org/infographic/|url-status = usurped|archive-date = January 5, 2016|website = F450C|access-date = 2015-12-17|language = en-US}}</ref><ref>{{cite web |title=Silicon Wafer |url=http://www.semiwafer.com/products/silicon.htm |access-date=2008-02-23  |archive-url=https://web.archive.org/web/20080220102757/http://www.semiwafer.com/products/silicon.htm |archive-date=2008-02-20 }}</ref> [[Semiconductor fabrication plant]]s, colloquially known as ''fabs'', are defined by the diameter of wafers that they are tooled to produce. The diameter has gradually increased to improve throughput and reduce cost with the current state-of-the-art fab using {{nowrap|300 mm}}, with a proposal to adopt {{nowrap|450 mm}}.<ref>{{cite web|url=http://www.intel.com/pressroom/archive/releases/20080505corp.htm|title=Intel, Samsung, TSMC reach agreement about 450mm tech|website=intel.com}}</ref><ref>[http://www.itrs.net/Links/2008Summer/Public Presentations/PDF/FEP.pdf ITRS Presentation (PDF)]{{Dead link|date=August 2018 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> [[Intel]], [[TSMC]], and [[Samsung]] were separately conducting research to the advent of {{nowrap|450 mm}} "[[prototype]]" (research) [[fab (semiconductors)|fab]]s, though serious hurdles remain.<ref>{{cite web |url=https://www.eetimes.com/450-mm-fab-debate-surfaces/ |title=450-mm fab debate surfaces |last=LaPedus |first=Mark |date=January 14, 2009 |website=EE Times |publisher=Aspencore |access-date=2021-05-09 |quote=As reported, Intel, TSMC and Samsung are separately pushing for the advent of 450-mm ''prototype'' fabs by 2012}}</ref>

[[File:Wafer 2 Zoll bis 8 Zoll 2.jpg|thumb|275px|{{convert|2|in|mm|adj=on}}, {{convert|4|in|mm|adj=on}}, {{convert|6|in|mm|adj=on}}, and {{convert|8|in|mm|adj=on}} wafers]]
{| class="wikitable sortable mw-collapsible" style="text-align:center"
|-
! Wafer size
! Typical thickness
! Year introduced <ref name=f450c />
! Weight per wafer
! 100&nbsp;mm<sup>2</sup> die per wafer
|-
| {{convert|1|in|mm|adj=on}}
|
| 1960
|
|
|-
| {{convert|2|in|mm|adj=on}}
| 275 [[μm]]
| 1969
|
|9
|-
| {{convert|3|in|mm|adj=on}}
| 375&nbsp;μm
| 1972
|
|29
|-
| {{convert|4|in|mm|adj=on}}
| 525&nbsp;μm
| 1976
| 10 grams <ref name="auto">{{cite web|url=http://wafercare.com/Page.aspx?id=1012|archive-url=https://web.archive.org/web/20131207002716/http://wafercare.com/Page.aspx?id=1012|archive-date=December 7, 2013|title=450 mm Wafer Handling Systems|date=December 7, 2013}}</ref>
| 56
|-
| 4.9&nbsp;inch (125&nbsp;mm)
| 625&nbsp;μm
| 1981
|
|95
|-
| 150&nbsp;mm (5.9&nbsp;inch, usually referred to as "6 inch")
| 675&nbsp;μm
| 1983
|
|144
|-
| 200&nbsp;mm (7.9&nbsp;inch, usually referred to as "8 inch")
| 725&nbsp;μm.
| 1992
| 53 grams <ref name="auto"/>
| 269
|-
| 300&nbsp;mm (11.8&nbsp;inch, usually referred to as "12 inch")
| 775&nbsp;μm
| 1999
| 125 grams<ref name="auto"/>
| 640
|-
| {{nowrap|450 mm}} (17.7&nbsp;inch) (proposed)<ref>{{cite web|url=https://www.eetimes.com/document.asp?doc_id=1169573|title=Industry agrees on first 450-mm wafer standard|first=Mark|last=LaPedus|website=EETimes}}</ref> 
| 925&nbsp;μm
| –
| 342 grams <ref name="auto"/>
| 1490
|-
| {{convert|675|mm|in|adj=on}} (theoretical)<ref>{{cite web|url=https://www.daifuku.com/solution/technology/semiconductor/|title=The Evolution of AMHS|website=www.daifuku.com|access-date=2018-12-02|archive-date=2019-04-08|archive-url=https://web.archive.org/web/20190408010203/https://www.daifuku.com/solution/technology/semiconductor/}}</ref>
| unknown
| –
| unknown
| 3427
|}
Wafers grown using materials other than silicon will have different thicknesses than a silicon wafer of the same diameter. Wafer thickness is determined by the [[mechanical strength]] of the material used; the wafer must be thick enough to support its own weight without cracking during handling. The tabulated thicknesses relate to when that process was introduced, and are not necessarily correct currently, for example the IBM BiCMOS7WL process is on 8-inch wafers, but these are only 200&nbsp;μm thick. The weight of the wafer increases with its thickness and the square of its diameter.  Date of introduction does not indicate that factories will convert their equipment immediately, in fact, many factories do not bother upgrading.  Instead, companies tend to expand and build whole new lines with newer technologies, leaving a large spectrum of technologies in use at the same time.