Atomic Layer Deposition of HfO 2 Using Alkoxides as Precursors
Atomic Layer Deposition of HfO 2 Using Alkoxides as Precursors
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DOI：
10.1021/jp037507r
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发表时间：
2004-08
影响因子：
3.3
通讯作者：
C. Mui;C. Musgrave
中科院分区：
文献类型：
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作者：
C. Mui;C. Musgrave
用密度泛函理论研究了以金属醇盐为金属和氧气为前驱体的HfO2薄膜的原子层沉积(ALD)。特别是，我们预测了用四乙氧基Hf[Hf(OEt)4]和水对HfO2进行ALD的化学机理。我们发现，ALD的半反应包括稳定的吸附络合物的形成和前体介导的配体交换机制。当以HF(OEt)4为金属前驱体，以水为氧源时，金属和氧的配体交换反应相对于反应物都是失活的。然而，与吸附的络合物相比，这些反应具有中等的势垒，而且去除乙醇副产物需要大量的脱附能量。然而，当以HfCl4为金属前驱体，以HF(OEt)4为氧源时，金属和氧气的半反应都具有较高的活化势垒(∼30−40kcal/m ol)。我们的结果表明，虽然HF(OEt)4.
We have used density functional theory to investigate the atomic layer deposition (ALD) of hafnium oxide (HfO2) thin films using metal alkoxides as both metal and oxygen precursors. In particular, we have predicted chemical mechanisms for the ALD of HfO2 using tetraethoxyl hafnium [Hf(OEt)4] and water. We find that the ALD half-reactions involve the formation of stable adsorbed complexes and precursor-mediated ligand-exchange mechanisms. When Hf(OEt)4 is used as the metal precursor and water is used as the oxygen source, both the metal and oxygen ligand-exchange reactions are unactivated with respect to the reactants. However, the reactions have moderate barriers relative to the adsorbed complexes, and the removal of the ethanol byproducts requires substantial desorption energies. However, when HfCl4 is used as the metal precursor and Hf(OEt)4 is used as the oxygen source, both the metal and oxygen half-reactions possess high activation barriers (∼30−40 kcal/mol). Our results imply that although Hf(OEt)4 ...