Growth mechanism of solution-deposited layers of the charge-transfer salt CuDDQ

Charge-transfer (CT) salts such as copper-2,3-dichloro-5,6-dicyano-p-benzoquinone (CuDDQ) are promising components of reversible resistive memory switching devices. In the study presented here, we report on the composition of CuDDQ layers grown from acetonitrile containing solution onto copper-coated silicon substrates. According to Rutherford Backscattering Spectrometry (RBS) experiments, the CuDDQ film is homogeneously composed of copper and DDQ across its whole thickness, and the ratio between copper and DDQ is 1:1. A complex between copper and acetonitrile has been identified by Electro Spray Ionization (ESI) time-of-flight mass spectrometry as the main source of copper ions for the CuDDQ layer formation. In contrast, if ethanol is used as solvent, no copper-ethanol complex can be discerned from the ESI mass spectrum. This finding underlines the vital role of acetonitrile as the main copper source for the complexation reaction with DDQ. The continuous availability of the copper-acetonitrile complex in solution during the growth of the CuDDQ layers explains their homogeneity as determined by RBS. (c) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Published in:
Physica Status Solidi B-Basic Solid State Physics, 244, 4346-4350
Presented at:
21st International Winterschool on Electronic Properties of Novel Materials, Kirchberg, AUSTRIA, Mar 10-17, 2007

 Record created 2012-07-04, last modified 2018-03-17

Rate this document:

Rate this document:
(Not yet reviewed)