Valery Ray Particle Beam Systems & Technology, Methuen, USA High-Throughput Milling of HAR Vias with Concentrated Gas Delivery PBS&T 9 th European FIB User Group Meeting EFUG 2005 Arcachon, France
11/20/2015 EFUG 2005, Arcachon, France2 Concepts of Concentrated Gas Delivery Commercial Shroud concentrator, or “Beehive” “Cupola” concentrator
11/20/2015 EFUG 2005, Arcachon, France3 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).
11/20/2015 EFUG 2005, Arcachon, France4 Main Chamber Vacuum as Function of Process Gas Pressure with Concentrator Factor of ~35 pressure reduction in main chamber of FIB system CCIG, Torr
11/20/2015 EFUG 2005, Arcachon, France5 Rate Comparison: SiO 2 Milling with XeF 2, Penta (2 Torr) vs. Shroud (0.8 Torr) Dose, nC Time, mm:ss Mill box, µm Factor ~ 3.5 throughput enhancement
11/20/2015 EFUG 2005, Arcachon, France6 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
11/20/2015 EFUG 2005, Arcachon, France7 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 current, and 0.8 Torr gas pressure.
11/20/2015 EFUG 2005, Arcachon, France8 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
11/20/2015 EFUG 2005, Arcachon, France9 Summary Concentrated gas delivery is viable for milling of 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.