Hi,

Is there anyone out there who's working or involved in the semiconductor industry?
I desperately need a piece of silicon, in wafer form. I need it for my Final Year Project experiments. Because I only need 1 piece, it is very hard to buy from those semiconductor companies who sell them in bulk.

Details: 

1. pure/new silicon wafer (untouched; doesnt contain any die, or hasnt been etched)
    (1 0 0) orientation, p-type
2. around 4 to 6 inch in diameter (size doesnt really matter)
3. Can be slightly defective; slightly scratched at the side, or slight deformation, so long      as more than 70-80% of the wafer is untouched. Semiconductor companys usually get rid of these kindda wafers.
4. I'm willing to a pay substancial amount. (please PM me the details and I'll give you the appropriate price)
If you have any information pertaining to this please reply in this thread or send me a PM.

Thanx alot.

Okay...

I need you guys opinion here.
" IS THERE SUCH THING AS NEGATIVE RESISTENSE?"

Since high school and 4 years in University, the basic thing I learned about resistence is that there is NO MATERIAL in this world that can give -ve resistence i.e you get -ve ohm in multimeter.

If you get such reading in first place, it is either that you have not calibrated your multimeter or the multimeter is faulty...
But in technical explaination, if you get -ve reading it means that the material you are testing is GIVING OUT energy, i.e generating its own energy, and Im not referring to dry cells or any other type of batteries.

A friend of mine was taking a reading of a wire (basically a grounding wire), and he got -ve reading. When I told him that his reading was wrong, he said that the reading is correct and it read -ve because the material is very good. The reading although only read -0.4ohm, it still makes a lot of difference in my line of job.

So I need you guys professional opinion whether the reading taken by my friend is correct and Im wrong or vice versa?
Note that this is not to prove who is right or wrong, but it is important that an accurate reading is taken due to the nature of job...

Negative differential resistance is something like negative temperature coefficient. The resistance of a material decreases when a controlled variable is being altered.