Talk:Gallium arsenide

It would be nice if this site contained the electronic properties of GaAs. For example it would be usefull to have the electron and nuclei's g-factors (lande factor) for this material. These are usefull qualities when considering qunatum dot's.

 JaM'S

I once toasted an array of near UV LEDs by having a voltage much to high connected to it. It smelled funny - could this smell have been gallium arsenide? Thanks, --Abdull 20:47, 28 August 2005 (UTC)

yea prob was , get high off that shit --unknown

What you smelled was probably a combination of arsine and metal vapor from the contacts. Arsine smells faintly like garlic and leaves a metallic taste in your mouth. And most people who know what it smells like are dead. -- 128.111.74.89 (talk) 00:17, 25 March 2008 (UTC)

The band gap at 300K is possibly wrong. This paper: ^[1] gives a different value of 1.424 eV at 297K (page R146, right side) and a value of 1.423 eV @300 K if you calculate it from the given formula (page R155, right side, upper paragraph). The reference given on the main article page however is rather cryptic and dubious in my eyes. --unknown physicist 192.53.103.119 (talk) 11:41, 8 October 2019 (UTC)

When I updated the table I left this there - does anyone think it should be in its own section in the article or left there?

Ryan Jones 21:27, 20 March 2006 (UTC)

I think it looks good there. The only interest people really have in GaAs is due to its electronic properties, so I think it deserves a place in the table. Thanks for updating the table, it looks good! Walkerma 07:10, 5 May 2006 (UTC)

Um, isn't GaAs gallium(III) arsenide? I don't think gallium forms any stable compounds in the +2 oxidation state. —Keenan Pepper 14:21, 19 June 2006 (UTC)

Of course it is gallium(III) arsenide, but more simply known as plain old gallium arsenide. There is no stable substance gallium(II) arsenide. Jaraalbe 21:40, 19 June 2006 (UTC)

Someone knows GaAs dielectric constant? Would be useful.

192.167.204.12 08:08, 14 September 2006 (UTC)

That varies, the static dielectric constant is 12.85, whereas the high frequency dielectric constant is 10.88. Look it up in^[1]. --unknown physicist 192.53.103.119 (talk) 12:16, 8 October 2019 (UTC)

Whats the price of Galium Arsnide? I'm interested in comparing it with silicon. Fresheneesz 23:42, 5 January 2007 (UTC)

Could we have a paragraph on how gallium arsenide is produced?

Can anyone post the work function of GaAs under normal conditions? —Preceding unsigned comment added by 128.84.45.160 (talk) 15:19, 21 July 2008 (UTC)

With all due respect, the pic is nonsensical. It shows a device of some kind, on a substrate of some kind. Nothing much to do with GaAs. Maybe a color picture of a boule, a chunk of crystal, or a wafer would be nice. Someone who has access non-copy right protected pic? There are countless pics on countless sites out there. —Preceding unsigned comment added by 70.130.66.196 (talk) 22:08, 26 November 2008 (UTC)

The last line in the Si advantages (which is currently "Unlike silicon cells, GaAs cells are relatively insensitive to heat. On the other hand, GaAs has an absorptivity so high it requires a cell only a few micrometers thick to absorb sunlight (crystalline silicon requires a layer 100 micrometers or more thick)") is very confusing. It sounds like it's talking about the advantages of GaAs, not Si. It should be moved, removed, or at least it should be made clear that this is about GaAs advantages, and why. AngusCA (talk) 20:11, 14 November 2009 (UTC)

Tweaked. Materialscientist (talk) 04:59, 15 November 2009 (UTC)

It still needs a bit of help. It seems to be talking about GaAs in a photoelectric cell. Is that it? The problem is that the explanation of the advantage (if that's what it is) needs to be closer to the bottom-line. AngusCA (talk) 17:48, 15 November 2009 (UTC)

Absorptivity? It seems there is some ccnfusion here. Again maybe too much photovoltaic-centric. Firstly, higher absorptivity results in thinner material requirement, not the other way around. 0.1 mm vs a few microns? It is also a matter of what wavelength. Where Si absorbs, GaAs is transparent! Wrong comparison. I will get back to this later. —Preceding unsigned comment added by 12.229.112.98 (talk) 23:28, 8 February 2010 (UTC)

The earliest GaAs computer that I'm aware of is the 4-bit prototype that the engineers working on Reagan's Star Wars project made. I think this is worth mentioning (or the real first one, if that wasn't it) because the article gives the impression that Cray did it first.

Otherwise this is a very good article. Unlike a lot of others at this level of esotericism, which are a lot of shop talk, this one respects WP:PCR well. AngusCA (talk) 20:25, 14 November 2009 (UTC)

Would it be possible to provide reference for the earliest GaAs computer? Or better say, just amend the article, with reference(s). Thank you. Materialscientist (talk) 04:59, 15 November 2009 (UTC)

If you're talking to me: no. Like I said, the Star Wars prototype is the earliest one I'm aware of. I don't know what the absolute earliest one is, I just know that the Star Wars prototype pre-dates whatever Cray came up w/in the 90s. AngusCA (talk) 17:51, 15 November 2009 (UTC)

Processor architecture: from dataflow to superscalar and beyond. Springer. 1999. p. 34. {{cite book}}: Unknown parameter |authors= ignored (help) might be the thing to look in.--Stone (talk) 18:02, 15 November 2009 (UTC)

I've updated this bit in the article. Thanks to AngusCA and Stone. Materialscientist (talk) 01:51, 16 November 2009 (UTC)

Si is highly abundant in the Earth's crust

But what is the abundance of Ga and As? Are these rare? Or just less common than Si? Maury Markowitz (talk) 14:41, 6 September 2011 (UTC)

refer to the article Abundance of elements in Earth's crust. Plantsurfer (talk) 08:42, 4 March 2013 (UTC)

As for gallium arsenide's color, I was working with a GaAs wafer last week, (measuring carrier lifetimes), and I noticed it had a very slight purplish color. Not like an eggplant; very slight but noticable, like tantalum if you have ever seen it. I thought it would be good to add what the material looks like compared with silicon or gallium nitride. 71.139.160.159 (talk) 06:43, 5 April 2012 (UTC)

This is a good article. I like the comparison of Si and GaAs in particular.

1. "With the changing of the band gap (0.4 nm/K) an algorithm calculates the temperature (all 250 ms)".

I find this sentence unclear. What's the meaning of "all 250 ms"?

2. "California lists gallium arsenide as a carcinogen, and it is considered a known carcinogen in animals. However, there is no evidence for a primary carcinogenic effect of GaAs."

What's the point of classifying GaAs as carcinogen if there is no evidence? I assume there is no scientific proof.

ICE77 (talk) 15:54, 22 July 2015 (UTC)

Inappropriate in an article on GaAs. Should recast as GaAs weaknesses v Si ?
Could merge the two sections and discuss GaAs and Si (and others) by property/characteristic ? - Rod57 (talk) 07:08, 3 January 2016 (UTC)

In the main article it states that Gallium has a 3+ oxidative in this compound. I am pretty sure this wrong. If you look at the crystal structure you can see that each gallium and arsenic atom have 4 bonds (can also not be explained by pure covalent bonds). This cannot be explained by 3+ oxidative state nor can it explain it semi-conductor capabilities. If more people agree, I will remove that line. — Preceding unsigned comment added by Bonnom (talk • contribs) 09:16, 11 September 2018 (UTC)

@Bonnom: The gallium has a formal charge of -1. Arsenic is more elctronegative than gallium, so each of the four covalent bonds counts as the gallium completely donating an electron to the arsenic (because all bonds that are not between two atoms of the same element are counted as completely ionic when calculating oxidation states), so that is a +4 oxidation state by itself. However, one must subtract the -1 formal charge, which results in a +3 oxidation state. Care to differ or discuss with me? The N^th User 01:56, 27 November 2018 (UTC)

The SMILES in the infobox does not represent the structure at all. I have been trying to create a better SMILES, but my attempts have not been rendering properly. (Removing the 3s from that example makes it render properly.) Can someone help me? Care to differ or discuss with me? The N^th User 01:38, 27 November 2018 (UTC)

I attempted to incorporated my SMILES crystal structure for diamond for gallium arsenide. It did not go well. Please help if you can. Care to differ or discuss with me? The N^th User 02:07, 27 November 2018 (UTC)

tried to add my best guess for the SMILES, the depiction at CDK depict https://www.simolecule.com/cdkdepict/depict.html looks reasonable. — Preceding unsigned comment added by SMILESmaster (talk • contribs) 11:12, 27 November 2018 (UTC)

I deleted the second sentence since it was meaningless. But I would argue that the entire section be deleted, rewritten and re-referenced, since its reference is weak - an investment article, not a technical one. ExpatSalopian (talk) 02:03, 4 January 2021 (UTC)