I don't think it means that. They have only recently been very gung ho about FDSOI.
But it does beg the question if nobody else goes for FDSOI will they have to drop it?
Is it in any case only a different route to FinFET-on-SOI, which is where bulk FinFET players will go anyway.
Multi foundry strategy is not an easy way to manage and gets maximum value out of 28nm and beyond technologies. Besides, Samsung is still suffering the role-conflict of IDM and foundry. I guess the reason Samsung still earns A6 order is due to a. cost/tech advantages in memory chips and leading 2.5D packaging technology b. TSMC or other foundries can not guarantee enough 32/28nm capacity.
The situation would be changed in 2013 due to capacity boomed and yield improved in TSMC. That would be the reason Samsung allures ST in foundry deal to fill the gap. I am just wondering that Samsung already got tapeout from Qualcomm and others but why Qualcomm still sticks on tsmc's 28nm supply. Same as nVidia. It is an interesting topic to be followed up. Besides, it also implies Global Foundries would be having some troubles with ST.
The SOI technology was developed by IBM, and PD (partially depleted) SOI was a big success up to 45-nm. But since then no product based on FD SOI has been developed yet although enormous resources have been spent by IBM and its fab club members including ST. The primary reason why ST has selected Samsung bulk 32/28-nm is that FD SOI technology at 32/28-nm and below has not demonstrated its manufacturability yet by IBM and its Alliances. This is because for 32/28-nm FD SOI to be fully depleted to suppress short channel effects the transistor channel or SOI body thickness of 8-nm or less and for 22/20-nm 6-nm or less are required. However, such ultrathin 8-nm Si channel layer for 32/28-nm and 6-nm for 22/20-nm are not manufacturable by Soitech, the largest SOI wafer supplier. What Soitech can deliver is 12-nm Si layer and 25nm Box layer for 22/20-nm nodes as announced at 2012 SOI conference. Soitech is also a member of IBM Alliances. The second reason why Samsung is selected is that Samsung published its 20-nm bulk technology at 2011 IEDM. Therefore, ST can extend to 20-nm bulk technology. IBM Alliances also published 20-nm bulk Si in 2012 VLSI, not significantly different from Samsung’s paper. However, when the planer bulk 20-nm will be manufactured is not announced yet by IBM or by Samsung. See my post for more information on this topic in “Ecosystem emerges around mobile chips tech,” EE Times 7/11/2012. SKim
Is ST going to be a fabless company? what about the Crolles and Catania facilities that will be stopped in Q4? Is ST management paving the way to loose their in house Si technology know-how? Europe is becoming more and more the periphery of technology arena.
Thanks for the contribution.
Your response would appear to be that planar HKMG on bulk CMOS from Samsung is an ST insurance policy against FDSOI not working at 32/28 and 22/20.
You also appear to assert that Soitec is not (yet) delivering thin enough top layer SOI to enable 32/28, 22/20 FDSOI.
I think ST will remain committed to analog, mixed-siganl and MEMS manufacturing. But it could be about to announce the withdrawal from digital IC production?
As you point out ST has spoken of several dropped days of production at Crolles and Catania in Q4.
And then disclosed that an updated strategic plan for the company is due to be presented in December.
It will be interesting to see what that contains.
ST is doing FD-SOI -- make no mistake about it -- it's a game changer. See today's interview with ST's JM Chery http://www.advancedsubstratenews.com/2012/10/exclusive-asn-interview-sts-jean-marc-chery-on-fd-soi-manufacturing/ He said: " ST/Crolles fab is now working to bring yield at production levels and complete the qualification of the technology, as done for any other. Phase-in of the technology at GlobalFoundries is planned to start Q1 2013, with process qualified and with production level yield foreseen for Q4 2013."
Interestingly, he also says they're moving right to 14nm with it.
@Michigan -- Soitec has no trouble with the wafers. SEH is also a supplier. Don't confuse the starting thickness with the finished thickness. Starting wafers have slightly higher top Si thicknesses, and some is etched away during manufacturing, hence what looks like a discrepancy is not.
Also, re: Samsung, Chery recently told David Manners that " And we can use Samsung for SOI if we need to". (see http://www.electronicsweekly.com/Articles/04/09/2012/54458/st-a-competitive-follower-in-process.htm)
Hi Kris -- yes, it's been a confusing issue for everyone! Basically the wafer mfgs quote top Si thickness of the wafers they ship, while the chipmakers quote the Si thickness once they're done processing the device -- which is always less.
Bruce Doris of IBM explained it nicely in an ASN article from 2010 http://www.advancedsubstratenews.com/2010/07/etsoi-substrates-what-we-need/: "The top silicon of the starting wafer (currently 12nm) has to be thicker than the final target thickness of the channel since some Si is used up in the process flow prior to final channel thickness definition. To reach full industrialization, we need a high-volume supply of wafers with thickness variation of less than +/-0.5nm with corresponding wafer-to-wafer uniformity." So now Soitec's shipping wafers for FD-SOI with Angstrom-level uniformity, meeting all the requirements. SEH (the world's biggest wafer mfg), recently told SemiMD that they are, too (http://semimd.com/blog/tag/seh/ )
BTW, back in 2010, IBM was getting post-processed Si thickness of 3.5nm, which could meet the requirements of the 11nm node, so you can imagine they've made all kinds of progress since then!
And as Soitec's pointed out on their website: "Uniformity of the top silicon layer of Soitec FD-2D wafers [[their wafers for FD-SOI]] is guaranteed to within +/-5Ĺ at all points on all wafers. This uniformity is equivalent to 5 mm over 3,000 km, which corresponds to approximately 0.2 inches over the distance between Chicago and San Francisco. For planar fully depleted SOI (FDSOI) CMOS technology, uniform thickness is crucial to controlling transistor Vt variations." Their current product spec sheet http://www.soitec.com/pdf/Soitec-FD-2D-product_brief.pdf indicates top Si of the FD-SOI wafer (this is pre-processed, as indicated above) down to 10nm.
Hope that helps!
I believe there are two challenges to be faced: a. Effective and efficient FDSOI wafer supply. 160K/month would be not enough in production phase.
b.$500 per wafer is too expensive to be adopted. For production, $250-300 would be affordable target.
thank you Adele for a clear and comprehensive explanation...BTW, would you have any interested in editing a small book on SOI? (I have been recently approached by one of the publishers I work with)...Kris
Article mentions "... already produced tape-outs of a dozen system-on-chip devices for mobile, ..."
any idea which mobile SoC is referred to here? Is it same NovaThor SoC?
FDSOI helps in multiple power saving techniques like dynamic body biasing, on chip regulator, sub-clock power gating etc., how these feature compares to HKMG process technology?