Accelerated Neutral Atom Beam Processing of Ultra-thin Membranes to Enhance EUV Transmittance February 22, 2015 1
Participation / Contacts Exogenesis Corporation, ANAB Technology Sean Kirkpatrick, Son Chau, Richard Svrluga Norcada Inc., MEMS / Membrane Technology Hooman Hosseinkhannazer, Yuebin Ning, Graham McKinnon International Sematech, Pellicle Investigation David Balachandran, Frank Goodwin Lawrence Berkeley National Lab, EUV Testing Eric Gullikson, Patrick Naulleau 2
Investigation Road Map Norcada, Inc. silicon membrane fabrication Lawrence Berkeley National National Lab Lab EUV Testing Exogenesis ANAB Processing 3
Norcada Membrane Technology Norcada is a MEMS and nanotechnology manufacturer in Edmonton, Canada Norcada offers ultrathin membranes for a variety of applications in industrial and scientific fields: o Poly and single crystal Silicon membranes o Silicon Nitride membranes o Polymeric membranes o Multilayer membranes with semiconductor materials and polymeric layers o Thin film semi-holey or holey features o Dual thickness membranes 4
Norcada Membrane Technology Norcada membranes are made in a variety of specifications: o Rib supports and silicon mesh structures o Encapsulated and protected ultrathin films o Membranes lateral size: 2µm to 100mm o Membrane thickness: 5nm to 20µm o Circular, polygonal and square membranes 5
Norcada Membrane Technology Norcada has the capacity to deliver thousands of devices per year All products are manufactured and packaged in cleanroom 6
Accelerated Neutral Atom Beam Technology (ANAB) High Intensity Flux Low Energy Particles (10-100+ ev) Electrically Neutral Surface Penetration < 3 nm 7
Accelerated Neutral Atom Beam Generation 1. Expansion of gas through a supersonic nozzle creates gas clusters Ar a few hundred to several thousand Ar atoms bound by weak interatomic forces 2/22/2015
Accelerated Neutral Atom Beam Generation 2. Clusters are ionized by electron impact and accelerated through HV + Individual atoms of an ionized 1000 atom cluster have 30 ev/atom after 30 kv acceleration 2/22/2015
Accelerated Neutral Atom Beam Generation 3. Collision of an accelerated cluster ion with an un-accelerated gas atom makes the cluster thermodynamically unstable + 2/22/2015
Accelerated Neutral Atom Beam Generation 4. An unstable cluster must release atom bonds in order to regain stability + + atoms released from a cluster continue to travel with the same speed and direction they had as part of the cluster 2/22/2015
Accelerated Neutral Atom Beam Generation + charged species neutral atoms deflector field 5. An electrostatic field is used to deflect residual charged species from the beam 2/22/2015
Accelerated Neutral Atom Beam Generation 6. Accelerated neutral atoms continue to transport as an intense collimated beam accelerated neutral atoms have energies controllable from 10 to 100 ev 2/22/2015
Accelerated Neutral Atom Beam (ANAB) Effects highly uniform sputtering and etching atomic level smoothing removal of nanoscale asperities amorphization to depths of 2 3 nm ultra-shallow doping surface composition modification deposition of ultra-thin films 2/22/2015
Atomic level smoothing EUV Lithography mask blank substrate After Accelerated Neutral Atom Beam Exogenesis process Ra 1.219 nm Rz 11.221 nm Ra 0.133 nm Rz 1.406 nm 15
Ultra shallow doping 1-3nm 16
Surface Modification of Copper With ANAB Carbon Doping for Enhanced Oxidation Resistance ANAB ANAB Control Control Oxidation accelerated on hot plate at ~300deg C in Atmosphere 17
Can ANAB Technology Improve Pellicle Membrane Material Performance At 13.5nm? Would ANAB processing to reduce thickness of ultra-thin membranes improve EUV (13.5 nm) transparency? Would ANAB processing to smooth membrane surfaces and remove surface asperities improve EUV transparency? Would ANAB processing to implant impurities into / onto surfaces of substrate materials severely diminish EUV transparency? 18
Lawrence Berkeley National Lab Reflectometry and Scattering Beamline (ALS 6.3.2) Beamline Specifications Wavelength precision: 0.007% Wavelength uncertainty: 0.013% Reflectance precision: 0.08% Reflectance uncertainty: 0.08% Spectral purity: 99.98% Dynamic range: 10 10 70 69.0 60 68.5 Reflectance (%) 50 40 30 20 68.0 67.5 12.90 12.95 13.00 PTB CXRO Precision Reflectometer 10 0 12.5 13.0 13.5 14.0 10 µm 150 µm beam size 1 µm positioning precision Angular precision 0.01 deg Wavelength (nm) 6 degrees of freedom Sample size up to 265 mm LG156 2/22/2015
Would ANAB processing to reduce membrane thickness improve EUV Transparency? Single crystal silicon membrane thinned from 100nm to 25nm %T at 13.5nm increased from 82.2% to 90.5% Polycrystalline silicon membrane thinned from 50nm to 25nm %T at 13.5nm increased from 90.9% to 94.4% 20
Would ANAB processing to smooth membrane surfaces improve EUV transparency? Control 100nm: %T at 13.5nm = 82.1% ANAB 1 side 50 nm: %T at 13.5nm = 85.8% ANAB 2 side X 25 nm: %T at 13.5nm = 87.0% 21
Would addition of ANAB impurities into/onto membrane surfaces reduce EUV transparency? Polysilicon membrane 50nm thick: %T at 13.5nm = 90.9% ANAB 1 side reduced to 25nm thick: %T at 13.5nm = 94.4% ANAB 1 side + 25nm ANAB Carbon: %T at 13.5nm = 90.2% 22
ANAB / Pellicle Membrane Investigation Summary Controlled thinning of membrane materials via ANAB processing can improve EUV transparency. Smoothing of membrane materials with ANAB can improve EUV transparency. Addition of ANAB impurities may provide enhanced performance to membrane materials without sacrificing EUV transparency. THANK YOU 23