Monday, November 10, 2008

ZnO Thin Film Using Sol-Gel Process

What is Sol-Gel Process?

The sol-gel process is a wet-chemical technique (Chemical Solution Deposition) for the fabrication of materials (typically a metal oxide) starting either from a chemical solution (sol short for solution) or colloidal particles (sol for nanoscale particle) to produce an integrated network (gel).

How We Can Prepare Zno Thin film Using Sol-Gel Process?

Its a simple process:-
Using zinc acetate and monoethanolamine at required concentration for the thin film ,mix it in a beaker using magnetic stirr and put few drops of Isopropyl alcohol using burrette untill the solution becomes transparent'.

1. Using Spin Coating method ,spinning the solution at 1500-5000 rpm for 15-40 seconds on
the glass/quartz substrate.
2. Bake it on 60 –150 °C hotplate for 1-5 minutes.
3. Bake it on 200-450 °C hotplate for 1-5 minutes.
4. Anneal it in 500- 700 °C oven for 3-60 minutes.
5. Repeat steps 1-4 several times, until desired film thickness is attained.

Alternate Route:-Can Be try---

---- Without monoethanolamine. zinc acetate and glycol-ethylen, heat at 150°C since 1h and the solide obtain is dissolve in ethanol.

-----Try zinc acetate dissolved in water or acetic acid; if in water you could easily complex with citric acid under stirring and mild heating and then evaporate on the hot plate the solution.

------Mixed zinc acetate + methanol + deionized water and add acetic acid to prevent zinc hydroxide precipitation. The solution quite stable for a long time

-----Use zinc-acetate in methanol and precipitate it with NaOH in ethanol. The precipitated zincoxide can be treated with stearic acid and redispersed in Hexane

1 comment:

istvan said...

Your recepy is really simple, but what do you mean "..required concentration..."?
Can you estimate the ZnO thickness after one spin on-heat treatment cycle?