Re: Required power for Si evaporation?

taeri wrote:
Hi all,

For some reason, I'd like to evaporate Si in the vacuum of 10^-7 torr.
Deposition rate should be controlled, in the range of 1 to 10 A per
minute.
I come to notice that the part of source as well as power supply for Si
cost around 40000 $,
which is too much for me.
So I decided to try just connecting power supply directly to the Si
wafer, with some modification of my chamber.
I'll use a coupon of undoped Si wafer, which has the size of 1cm by 0.5
cm, with thickness of 0.5 mm.
And, I'm planning to use direct DC current for heating.
Problem is that I don't know how much power is required, and what kind
of power supply should be used.

Is anybody there who has experience over this kind of problem?
Can you give me an idea the magnitude of power for Si evaporation?
And, can normal e-beam evaporator, such as Omicron EFM single
evaporator, do evaporation of Si?

Taeyon


Perhaps a too simple an answer

Take boiling point of Silicon 2628 K

multiply time Boltzmann constant and Avogadro's number

This gives approximation of vaporization energy per mole

Calculate moles in your sample

That will give base energy for evaporating sample.

Power required is then related to processing rate (moles/hr).

Richard

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