Hafnium oxide deposition (CVD): Difference between revisions

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:HfO<sub>2</sub>  +  2 Cl<sub>2</sub>  +  C  →  HfCl<sub>4</sub>  +  CO<sub>2</sub>
:HfO<sub>2</sub>  +  2 Cl<sub>2</sub>  +  C  →  HfCl<sub>4</sub>  +  CO<sub>2</sub>
*Chlorination of hafnium carbide above 250&nbsp;°C.
*Chlorination of hafnium carbide above 250&nbsp;°C.
The result of those chemical reactions is a crystalline powder with a melting point of 432&nbsp;°C


===Processing steps===
===Processing steps===


https://patents.google.com/patent/CN100356519C/en
https://patents.google.com/patent/CN100356519C/en

Revision as of 15:29, 11 October 2022

The base of this chemical recipe and processing is Hafnium-Tetrachloride, as it can be seen in the picture.

Hafnium-Tetrachloride

You might notice that Hafnium-Tetrachloride is a solid crystal at room temperature, which is kind of a problem considering that we wanna use it as a vapor in our CVD furnace, in order to react it with oxide for obtaining a Hafnium-Oxide thin film layer.

Chemical properties of Hafnium-Tetrachloride

Hafnium-Tetrachloride


HfCl4 can be produced by several related procedures:

  • The reaction of carbon tetrachloride and hafnium oxide at above 450 °C;
HfO2 + 2 CCl4 → HfCl4 + 2 COCl2
  • Chlorination of a mixture of HfO2 and carbon above 600 °C using chlorine gas or sulfur monochloride:
HfO2 + 2 Cl2 + C → HfCl4 + CO2
  • Chlorination of hafnium carbide above 250 °C.

The result of those chemical reactions is a crystalline powder with a melting point of 432 °C

Processing steps

https://patents.google.com/patent/CN100356519C/en