Talk:Gallium nitride

Developments

I'm not sure who originally wrote that high quality epitaxial GaN is "impossible to grow", but I changed it to "difficult". Mainly I did this because I know for a fact that it is possible, since I have read about 10 journal articles describing how to do it, and I watched someone do it in a lab last week, but I think maybe I should have just deleted the entire paragraph. It's outdated at best. Any objections? Jermor 17:11, 3 July 2007 (UTC)

If you know it is possible, and you have the references at hand, then why delete it. Maybe rewrite it into a section about 'growing high quality epitaxial GaN'? --Dirk Beetstra ^{T C} 17:18, 3 July 2007 (UTC)

I guess by "difficult" one means comparing it with other semiconductor material systems grown by comparative techniques. One measure of quality is the defect density which is certainly higher for GaN (still best in III-nitrides) than GaAs or Si. Moreover, morphology for gaN is still poor for these semiconductors. One of the reasons for such a quality is the absence of native substrates to grow nitrides on. I must say, however, that there is a tremendous amount of work going on in this respect with growth of bulk-like GaN by HVPE and high pressure techniques. Pranobmisra 20:14, 15 August 2007 (UTC)Pranob Misra

I appreciate the explanation and the comparison to Si and GaAs. GaN can also be grown by MOCVD and MBE, and despite the lack of a convenient substrate, buffer layers and other techniques are making the process a lot better. By the way, someone has made significant improvements to this article, and it looks a lot better now. Jermor (talk) 01:03, 5 December 2007 (UTC)

Cost

Are these crystals what make blue diode lasers so expensive? Where does the high cost come from? -- Beland (talk) 22:10, 27 July 2008 (UTC)

The growth of the crystals itself is fairly expensive, as are the sapphire substrates traditionally used 80.194.76.179 (talk) 07:10, 23 August 2011 (UTC)

Sensitivity to radiation

I suspect the author of the intro section meant to say "its susceptibility to ionising radiation damage is low", rather than "sensitivity", since the latter could be interpreted as a statement about its photo-sensitivity (stated as current per unit particle energy), when used as a photo-diode/detector.

Suggest a rewording along these lines.

Matt Whyndham (talk) 10:16, 3 February 2009 (UTC)

GaN on Si

This is a major breakthrough and tons of material is published, and it is an industrial and commercial process. I take offense at the removal of the related single sentence especially with the rather flimsy excuse of "inaccesibility" of the references. EDN is a mainstream publication for the electronic industry. Is it possible that the editor who reverted has an ultirior motive? One can not help but feel that way. It would have been far more constructive to fix the reference or find a better references since GaN on Si is a rather significant milestone in technology and its absence from the whole article is an oddity. —Preceding unsigned comment added by 12.229.112.98 (talk) 23:13, 9 February 2010 (UTC)

This looks like the addition and revert.

 More recently, GaN has been succesfully grown on Si, making it possible to scale up production and lower costs drastically<ref>"GaN-on-Si technology leveraged for power switches and white LEDs", EDN, July 2009.</ref><ref>“GaN-on-Si Reliability: A Comparative Study between Process Platforms”, S. Singhal, A. Chaudhari, A.W. Hanson, J.W.Johnson, R. Therrien, P. Rajagopal, T. Li, C. Park, A.P. Edwards, E.L. Piner, I.C. Kizilyalli, K.J. Linthicum, ROCS (2006)</ref>.

Looks like 2 decent sources. Reverter could have just marked it {{dubious}} if there was any reason to doubt it. Sources don't need to be accessible online. - Rod57 (talk) 01:13, 21 December 2015 (UTC)

Google found 2nd source : GaN-On-Si Reliability: A Comparative Study Between Process Platforms (doi=10.1109/ROCS.2006.323391), Ist source : GaN-on-Si technology leveraged for power switches and white LEDs - look fine to me. - Rod57 (talk) 01:21, 21 December 2015 (UTC)

Need a link to disambiguation

I ended up on this page after googling GAN. I know I need to add some sort of disambig pointer at the top of the page, but which template do I use? Maury Markowitz (talk) 12:25, 3 June 2014 (UTC)

Comments and suggestions

This article could be expanded. It seems to have a reduced amount of information. It would be nice to have a section with electrical, chemical and optical properties, especially for semiconductors and a possible comparison to SiC technology which is popular at this point in time.

ICE77 (talk) 06:12, 24 June 2015 (UTC)

GaN and temperature - ~400 °C

Article says " The large band gap means that the performance of GaN transistors is maintained up to higher temperatures than silicon transistors" but up to what temperatures ? - Rod57 (talk) 02:45, 21 December 2015 (UTC)

As of now, 19 June 2018, I see a reference to GaN working at ~400 °C (note 23). ICE77 (talk) 23:48, 19 June 2018 (UTC)

MSI or LSI /Digital logic chips

Has there been any use or discussion of using GaN for LSI processors or memory chips ? or any digital logic ? - Rod57 (talk) 07:18, 23 June 2017 (UTC)

found some experiments from 2004 : GaN HFET digital circuit technology - just SSI, eg 217 transistors, 31 stage ring oscillator, gates ~ 3x4 μm, gate delays increase at higher temps.

even CMOS : HRL Laboratories claims first gallium nitride CMOS transistor fabrication. Feb 2016 "gate widths of the PMOS and NMOS transistors were 500μm and 50μm, respectively." - Rod57 (talk) 08:04, 23 June 2017 (UTC)

add number of devices on CMOS chip, and clock rate - Rod57 (talk) 11:08, 22 June 2021 (UTC)

Inappropriate adverb - not recent - fixed

The article says "The environment, health and safety aspects of gallium nitride sources (such as trimethylgallium and ammonia) and industrial hygiene monitoring studies of MOVPE sources have been reported recently in a review.[34]"

Note 34 is dated 2004 which is 14 years ago. I'm not sure the text should still say "recently". ICE77 (talk) 23:45, 19 June 2018 (UTC)

 Done

Commercial Use of GaN power devices

I suggest the article introduction should be updated to mention the increasingly widespread use of 650V GaN power devices in consumer electronics. Probably only needs a single sentence? [Dell, Apple, Harman, Samsung, Lenovo all now use GaN in AC power adapters] 75.135.150.19 (talk) 21:54, 5 July 2023 (UTC)

Enhancement-mode devices

The paragraph:

"Unlike silicon transistors which switch off due to power surges, GaN transistors are typically depletion mode devices (i.e. on / resistive when the gate-source voltage is zero). Several methods have been proposed to reach normally-off (or E-mode) operation, which is necessary for use in power electronics: ... "

...should be updated to reflect the fact that normally-off GaN power transistors have been in production for several years now from a number of semiconductor manufacturers. 75.135.150.19 (talk) 21:58, 5 July 2023 (UTC)