Purchasing semiconductor substrates I'd like to make a comparison of prices, availability and properties of semiconductor substrate layers like Si, Ge, GaP, AlN etc. I wonder what are the problems related to getting such data, what are the leading companies that sell such things, what's the quality, waiting time and so on. I'm not going to buy one, It's just a little research, that's why I ask here and not the companies directly. Your own experiences (what problems you've encountered and maybe some sample prices or company names?) are much appreciated.
 A: As an engineer, I've had to get pricing on stuff I wasn't going to buy many times in the past. I doubt you'll find a website which will have the prices, but you can find them yourself in a few hours work. What you do is this:
Call them up and ask for a "sales rep" (abbreviation for "sales representative" but nobody calls them by the full name) tell him/her that you're working at a physics lab (I presume you are) and that you need "budgetary pricing". This is pricing that includes no discounts. Budgetary pricing is not an offer to sell. So if the price suddenly goes through the roof because of a revolution in some obscure country budgetary pricing won't get them into trouble. They should give this to you without a lot of trouble as it's not secret information. I've always assumed that they don't put it on their websites because (a) it changes, and (b) it might be construed as being an offer to make a contract.
And if you can't get information from their website, ask them to give you a "data sheet". That should be all you need.
Hey, I'll get you started. Here's a company that sells wafers for the valley:
http://www.svmi.com/
Here's their extensive non silicon product line:
http://www.svmi.com/non-siliconwafers.aspx 
Here's their contact info:
Tel:  408.844.7100
Fax: 408.844.9470
Email: sales@svmi.com  
Now when you talk to them, do not sound like a complete idiot. Make sure you know everything about their product BEFORE you pick up the phone. Make yourself a temporary expert on their product line. Know what size you're interested in and what level of quality, etc. Decide in advance what year you're asking for (new stuff gets cheaper with time), and the approximate quantity.
If possible, use their website to determine the actual product number for the item you're interested in. By giving them a part number you are making their job very easy. Sales people are not, by nature, inclined to annoy potential customers. Make it easier for them to give you a price than it would be for them to tell you to go away. If you give them a part number it will be very easy to look up a number for you. Do not waste their time by asking for them to speculate about exactly how these prices will change in the future. (But if they're bored they might have time to talk to you about this.) They should be able to tell you that they "expect that these prices will drop as production ramps up", or give you a vague idea, and maybe you'll get lucky. But remember that you're asking industry to do you a favor for no real good reason.
A: I was looking for a company who can provide Si (and potentially other) wafers of various types, and I can say the following:
1) You will have a hard time finding 'fixed' pricelist. Companies are not ready to quote you unless you are ready to buy XXX amount. 'I am just checking prices around' not gonna work.
2) Price is drastically different if you are getting standard wafer (which is produced in mass quantity for fabs). If you are getting non-standard wafer you not going to get price/wafer price (or it's going to be ridiculously high). You going to be quoted for crystal growth and slicing+finishing separately. And of course price is negotiable for large quantity.
3) You can get almost any needed purity (=more recrystallization passes). It just costs additional money. (so going from 1kOhm to 10kOhm Si resistance adds 30% to the crystal price before slicing)
4) Delivery of stock wafers depends on your luck & their laziness. Custom crystals take ages to make.
