Open AccessCompact, 3D-Printed Electron Impact Ion Source with Microfabricated, Nanosharp Si Field Emitter Array Cathode
Author(s) -
Chenye Yang,
Luis Fernando Velásquez–García
Publication year - 2019
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1407/1/012019
Subject(s) - field emitter array , common emitter , field electron emission , materials science , cathode , torr , electron gun , optoelectronics , surface micromachining , silicon , fabrication , voltage , electron , cathode ray , nanotechnology , chemistry , electrical engineering , physics , medicine , alternative medicine , pathology , quantum mechanics , thermodynamics , engineering
We report the design, fabrication, and characterization of a novel miniature electron impact gas ionizer manufactured via silicon micromachining and high-resolution 3D printing. The ionizer uses an array of 2,500 gated silicon nano-sharp field emitters (20 μm emitter pitch) as cathode and a set of additively manufactured, finely featured polymer and metallic parts as three-dimensional ion-generating structure. Finite element simulation of a gated field emitter tip predicts a start-up bias voltage equal to 64 V –close to the 62 V turn-on bias voltage estimated via experiments. The Si field emitter array emits 124.5 μA of electron current with ~60% gate transmission while operating at 200 V. The ionization efficiency of the gas ionizer is linear with pressure, reaching values as high as ~0.4% at 5×10 −4 Torr.