Bchir Omar J, Green Kelly M, Ajmera Hiral M, Zapp Elizabeth A, Anderson Timothy J, Brooks Benjamin C, Reitfort Laurel L, Powell David H, Abboud Khalil A, McElwee-White Lisa
Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611, USA.
J Am Chem Soc. 2005 Jun 1;127(21):7825-33. doi: 10.1021/ja043799d.
A mixture of the tungsten allylimido complexes Cl(4)(RCN)W(NC(3)H(5)) (3a, R = CH(3) and 3b, R = Ph) was tested as a single-source precursor for growth of tungsten nitride (WN(x)) or carbonitride (WN(x)C(y)) thin films. Films deposited from 3a,b below 550 degrees C contained amorphous beta-WN(x)C(y), while those deposited at higher temperatures were polycrystalline. Film growth rates from 3a,b ranged from 5 to 10 A/min over a temperature range of 450-650 degrees C, and the apparent activation energy for film growth was 0.15 eV. A plot of the E(a) values for deposition from Cl(4)(RCN)W(NR') [R' = Ph, (i)Pr, allyl] against the N-C imido bond strengths for the analogous amines R'NH(2) is linear, implicating cleavage of the N-C bond as the rate-determining step in film growth. The correlation of mass spectral fragmentation patterns for Cl(4)(RCN)W(NR') with film properties such as nitrogen content supports the significance of facile N-C bond cleavage in film growth.
测试了钨烯丙基亚胺配合物Cl(4)(RCN)W(NC(3)H(5))（3a，R = CH(3)；3b，R = Ph）的混合物作为生长氮化钨（WN(x)）或碳氮化物（WN(x)C(y)）薄膜的单源前驱体。在550℃以下由3a、3b沉积的薄膜含有非晶态β-WN(x)C(y)，而在较高温度下沉积的薄膜是多晶的。在450 - 650℃的温度范围内，3a、3b的薄膜生长速率为5至10 Å/分钟，薄膜生长的表观活化能为0.15 eV。Cl(4)(RCN)W(NR') [R' = Ph、(i)Pr、烯丙基]沉积的E(a)值与类似胺R'NH(2)的N - C亚胺键强度的关系图呈线性，这表明N - C键的断裂是薄膜生长中的速率决定步骤。Cl(4)(RCN)W(NR')的质谱碎片模式与诸如氮含量等薄膜性质的相关性支持了在薄膜生长中N - C键容易断裂的重要性。
