Valery Ray Particle Beam Systems & Technology, Methuen, USA High-Throughput Milling of HAR Vias with Concentrated Gas Delivery PBS&T FIB User GroupISTFA 2005 San Jose, CA

5/20/2015 FIB User Group, ISTFA Concepts of Concentrated Gas Delivery Commercial “Shroud” concentrator “Cupola” concentrator

5/20/2015 FIB User Group, ISTFA Imaging through Shroud Concentrator: FOV 20, 5.8pA Beam, Dielectric Sample Images taken through Shroud gas concentrator (left) have lower S/N then images taken with Penta nozzle (right).

5/20/2015 FIB User Group, ISTFA Main Chamber Vacuum as Function of Gas Pressure with “Shroud” Concentrator Factor of ~35 pressure reduction in main chamber of FIB system CCIG, Torr

5/20/2015 FIB User Group, ISTFA Comparison of 5µm via Milling in SiO2 with XeF 2, Penta (2 Torr) vs. Shroud (0.8 Torr) Dose, nC Time, mm:ss Mill box, µm Factor ~ 3.5 throughput enhancement

5/20/2015 FIB User Group, ISTFA Endpointing with Gas Concentrator: Secondary Electron Signal Secondary electron endpoint of 5µm deep via made by 0.3x0.3µm mill box, 5.8 pA beam current, and 0.8 Torr XeF 2 gas pressure, shroud gas concentrator. 0V bias 2V bias

5/20/2015 FIB User Group, ISTFA Endpointing with Gas Concentrator: Sample Absorbed Current Stage current endpoint of 5µm deep via made by 0.3x0.3µm mill box, 5.8 pA beam, and 0.8 Torr XeF 2 gas pressure.

5/20/2015 FIB User Group, ISTFA Indirect Comparison of Via Profile: Penta vs. Shroud (Beehive) FOV 5µm Vias milled by Beehive are expected to have straighter profile then vias milled by Penta

5/20/2015 FIB User Group, ISTFA Summary  Concentrated gas delivery is viable for milling of multiple access vias in FIB Circuit Edit.  Provides enhanced throughput and reduced pressure in main chamber.  Endpoint is reliable with sample absorbed current and secondary electrons.