Bonjour!

Result of Silicon crystal analyzation shown that there is an amount of arsenic As atoms in silicon crystal at Concentrate percentage which is 0.0002%. Assuming if conductivity concentration which promote by heat is an eliminated amount.

Find out the electrical conducting density?

Where Molarity of silicon = 12.1cm3/mole.

Answer:

We get N-type semiconductor

Density= w/v....(1)

V= Moles#/Molarity....(2)

*1/Calculation of moles number:*

Moles#=w/M.wt....(3)

= .0002*100/28.1

=**7.117*10^-4 mole **

*2/ Calculation of volume:*

back to equation #2

V=7.117*10^-4/12.1

=**5.88*10-5 cm3 **

3/W of Si =moles#/atomic mass

= 7.117*10^-4/28.086

**= 2.534*10^-5gm **

Back to density

D = 2.534*10^-5/5.88*10^-5

= **0.4309 gm/cm3 **

Question:

where could the previous answer take me to?

Question:

Dose electrical conducting density try to tell me something about which of charge conductive (holes or electrons) have majority on other?

Information:

I'm already know that it's N-type SC which means the charge conductive is electron.

Question:

Did I need to find the electron numbers?

I need a diagram of conducting band,valance band and energy gap between them.

Come on chmists do something about it.