Understanding the depth distribution of organic species is of great importance for the manufacture of a number of innovative devices. There are many analytical methods that can measure these depth distributions to varying levels of accuracy and sensitivity. Reference materials are useful to establish the depth scale, depth resolution, sensitivity and linearity of response for these methods and to benchmark performance between different techniques.

NPL has developed a highly useful material for this purpose, which consists of alternating layers of two molecular materials, Irganox 1010 and Irganox 3114, their structures are given below. Links to the papers describing the development of this material and papers arising from its use in VAMAS interlaboratory study TWA2 A3(d) are provided at the bottom of the page.

The organic multilayer (OML) reference and test materials are produced by vacuum evaporation onto (10 mm x 10 mm) silicon wafers, with a usable area of approximately 8 mm x 8 mm. The nominal VAMAS architecture for OML samples is four Irganox 3114 marker layers at 50 nm, 100 nm, 200 nm and 300 nm depths in a matrix of Irganox 1010. The marker layer thicknesses are 1 nm, 3 nm or 10 nm. Each OML sample is accompanied by an individual datasheet providing the thickness of each layer calibrated by spectroscopic ellipsometry. The layer thicknesses are produced with better than 0.5 nm precision and a variation in thickness across the sample of better than 1% for OML reference materials and better than 4% for OML test materials. Please note that these are not certified reference materials

Indicative prices for OML with the VAMAS architecture described above are £500 for test materials and £750 for reference materials. Different architectures and layer thicknesses are also available on request.

Contacts

To obtain quotes and order these materials:
Customer Service tel: +44 20 8943 8637
E-mail: nanoanalysis_enquiries@npl.co.uk

For general information on these materials and their use:
Steve Spencer
Surface & Nanoanalysis
National Physical Laboratory
Hampton Road
Teddington
Middlesex
TW11 0LW
UK
Email: nanoanalysis@npl.co.uk
Tel: +44 20 8943 6620
Fax: +44 20 8943 6453

Links

Organic depth profiling at NPL

Quantitative Molecular Depth Profiling of Organic Delta-Layers by C60 Ion Sputtering and SIMS A. G. Shard, et al: J. Phys. Chem. B 112, 2596, (2008)

Incident Angle Dependence in Polymer TOF-SIMS Depth Profiling with C60 Ion Beams S. Iida, et al: e-J. Surf. Sci. Nanotech. 7, 878, (2009)

Molecular Depth Profiling with Cluster Secondary Ion Mass Spectrometry and Wedges D. Mao, et al: Anal. Chem. 82, 57 (2010)

Organic Depth Profiling of a Nanostructured Delta Layer Reference Material Using Large Argon Cluster Ions J. L. S. Lee, et al: Anal. Chem. 82, 98 (2010)

Sample cooling or rotation improves C60 organic depth profiles of multi-layered reference samples: Results from a VAMAS interlaboratory study P. Sjövall, et al: J. Phys. Chem. B 114, 769 (2011)

Dual beam depth profiling of organic materials: Variations of analysis and sputter beam conditions D. Rading, et al: Surf. Interface Anal. 43, 198 (2011)

VAMAS Interlaboratory Study on Organic Depth Profiling 1: Preliminary Report A. G. Shard, et al: Surf. Interface Anal. 43, 510 (2011)