Deposition of ultrathin parylene C films in the range of 18 nm to 142 nm: Controlling the layer thickness and assessing the closeness of the deposited films

Abstract In this work we describe the deposition of ultrathin parylene C films in the range of 18 nm to 142 nm. Experimental results were obtained from measurements with a commercially available parylene deposition system which was equipped with a quartz crystal microbalance in order to monitor the thickness of the applied layers as well as the deposition rate in real time during the deposition process. This paper will supply the data required to conveniently reproduce the deposition of ultrathin films in the range of well below 100 nm. Furthermore we describe a simple and robust method to test if the applied parylene layers are closed which may be an important aspect to consider if ultrathin layers are to be used as protective coatings or the like. For an exemplary planar electrode structure, we have found a parylene layer of 35 nm to be the thinnest possible closed layer.

[1]  Chang Liu,et al.  Parylene surface-micromachined membranes for sensor applications , 2004, Journal of Microelectromechanical Systems.

[2]  Y. Tai,et al.  Yield strength of thin-film parylene-C , 2003, Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS 2003..

[3]  Y. Tai,et al.  Surface-Micromachined Parylene Dual Valves for On-Chip Unpowered Microflow Regulation , 2007, Journal of Microelectromechanical Systems.

[4]  Peter K. Wu,et al.  Surface reaction and stability of parylene N and F thin films at elevated temperatures , 1995 .

[5]  David Bullen,et al.  Development of an end-point detector for parylene deposition process , 2003 .

[6]  M. Szwarc Some remarks on the CH2[graphic omitted]CH2 molecule , 1947 .

[7]  M. Spivack,et al.  Parylene Thin Films for Radiation Applications , 1970 .

[8]  N. Nishimura,et al.  Flexible microfluidic devices supported by biodegradable insertion scaffolds for convection-enhanced neural drug delivery , 2009, Biomedical microdevices.

[9]  T. Lu,et al.  A Model for the Chemical Vapor Deposition of Poly(para-xylylene) (Parylene) Thin Films , 2002 .

[10]  Kerstin Länge,et al.  Chemical modification of parylene C coatings for SAW biosensors , 2007 .

[11]  K. Gleason,et al.  Overview of Strategies for the CVD of Organic Films and Functional Polymer Layers , 2009 .

[12]  M. A. Spivack,et al.  Determination of the Water Vapor Permeability and Continuity of Ultrathin Parylene Membranes , 1969 .

[13]  W. R. Dolbier,et al.  Parylene-AF4: a polymer with exceptional dielectric and thermal properties , 2003 .

[14]  M. Junk,et al.  A Study of Parylene C Polymer Deposition Inside Microscale Gaps , 2007, IEEE Transactions on Advanced Packaging.

[15]  M. Rapp,et al.  Polymer coating behavior of Rayleigh-SAW resonators with gold electrode structure for gas sensor applications , 2007, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[16]  Joseph F Rizzo,et al.  Biocompatibility of materials implanted into the subretinal space of Yucatan pigs. , 2006, Investigative ophthalmology & visual science.

[17]  W. F. Gorham A New, General Synthetic Method for the Preparation of Linear Poly‐p‐xylylenes , 1966 .

[18]  J. Senkevich Thickness effects in ultrathin film chemical vapor deposition polymers , 2000 .

[19]  A. Sharma Parylene C at subambient temperatures , 1988 .

[20]  D. M. Mattox,et al.  The Foundations of Vacuum Coating Technology , 2003 .

[21]  H. Ache,et al.  Covalent photolinker-mediated immobilization of an intermediate dextran layer to polymer-coated surfaces for biosensing applications. , 1998, Biosensors & bioelectronics.

[22]  M. Szwarc New monomers of the quinoid type and their polymers , 1951 .

[23]  K. Jensen,et al.  Transition Metals for Selective Chemical Vapor Deposition of Parylene-Based Polymers , 2000 .

[24]  T. Lu,et al.  The facile surface modification of poly(p-xylylene) ultrathin films , 2003 .