Accession Number : AD1051603


Title :   Engineered Surfaces to Control Secondary Electron Yield for Multipactor Suppression


Descriptive Note : Technical Report,01 May 2015,01 Oct 2017


Corporate Author : Air Force Institute of Technology WPAFB United States


Personal Author(s) : Sattler, James


Full Text : http://www.dtic.mil/dtic/tr/fulltext/u2/1051603.pdf


Report Date : 14 Sep 2017


Pagination or Media Count : 224


Abstract : A significant problem for satellites, vacuum electron devices, and particle accelerators is multipactor: an avalanche of electrons caused by recurring secondary electron emission (SEE) in a time-varying electric field. The consequences of multipactor range from temporary to permanent device failure. This research studied how surface topography can be engineered to minimize SEE and suppress multipactor. Two new semi-empirical models (one based on a 2D pore, the other based on a 3D pore) were developed to predict the secondary electron yield (SEY) of a porous surface based on pore aspect ratio and porosity. The models were validated with experimental SEY measurements of microporous gold surfaces. The more accurate 3D model predicts that a porous gold surface with pore aspect ratios = 2.0 and porosity = 0.5 will control the maximum SEY to near unity, providing a multipactor-resistant surface. Both the SEY models and experimental results confirm the understanding that the ability of a porous surface to control SEY is not dependent on pore size


Descriptors :   RADIO FREQUENCY AMPLIFIERS , radio frequency devices , photolithography , electron beam lithography , measurement , fabrication , dielectrics , electron energy , electron emission , microwaves , circuits , harmonics


Subject Categories : Radiofrequency Wave Propagation


Distribution Statement : APPROVED FOR PUBLIC RELEASE