NRL_Specifications_for_Electron_Beam_Evaporator.pdf

Specifications for Electron Beam Evaporator

1. The Naval Research Laboratory (NRL) has a requirement for an electron beam evaporator for the deposition of metallic thin films for semiconductor devices.

A. The primary requirement is for an electron-beam evaporator for the automated deposition of metallic thin films onto semiconductor device wafers via blanket deposition or lift-off processes.

The evaporator must be compatible with wafers up to 150 mm in diameter as well as multiple parts as small as 5 mm in length and width. The tool must readily evaporate metals such as Cr, Ti, Ni, Al, Au, Pt, Ag, Cu, V for example. The tool must utilize recipe-driven evaporation procedures and have fully-automated process, e.g. pump down, vent, wafer transfer, pump regeneration, etc.

The system must be a commercial product with demonstrated field use.

B. The process chamber must be built with 304L stainless steel. The side plates should be removable to allow for future upgrades and be o-ring sealed while the aluminum front-access door should be hinged and o-ring sealed for maximum access to the chamber and hearth for changing source material and maintenance. The frame should provide for an enclosed base cabinet and instrument rack with removable panels for maintenance. The chamber and load-lock should not have any additional enclosure to allow for easy maintenance. The frame should have caster wheels and leveling feet. The chamber must have a manually operated viewport shutter for easy inspection and must come with two (2) removable 304L stainless steel chamber liners for subsequent cleaning. The base flange should allow for an electron-beam source and ability for two (2) thermal boat assemblies as future potential upgrade. The chamber should have appropriate vacuum gauges that read from atmosphere to 10-9 Torr, e.g. ion and convection gauges. The process chamber should maximize conductance to the high vacuum pump via minimizing pumping distance, e.g. mounting pump directly to chamber by bypassing pumping nipple. A water distribution system with manual shut off valves and interlocked flow switches must be included.

A single service drop, e.g. 208 VAC, 60 Hz, three phase (5 wire), connection should supply power to the entire tool and accessories via power distribution unit with EMO protection and appropriate safety interlocks.

C. The main chamber must be pumped using a 1500 L/S or better cryogenic pumping system (Cryo- Torr-8 or equivalent) with water-cooled compressor, 3-position gate valve, 20’ He lines, and automated regeneration capability. The roughing pump must be an oil-free 6.7 cfm or better scroll pump (nXDS10i or equivalent) and be located remotely from system frame. The minimum base pressure of the chamber must be at least 5x10-8 Torr. The chamber pumping and venting process must be fully automated. The foreline should have appropriate vacuum gauge, e.g. convection gauge.

D. The system must have a load lock to transfer up to one 150-mm diameter wafer or multiple smaller substrates via the ability to clip pieces to the holder assembly. The single substrate load lock should be fully-automated with appropriate vacuum gauges and valves. The load lock must have its own high vacuum pump, 67 L/s turbomolecular pump or better, and can share the process chamber scroll pump.

E. The evaporator must have an 8 pocket (12 cc) electron beam source with at least 5 kW solid-state power supply with programmable sweep and automatic crucible indexing. At least sixteen (16)

Fabmate crucibles should be included. The source must have a pneumatically actuated shutter.

The source should contain no dynamic water-to-vacuum o-ring seals to minimize potential water leaks into the chamber. Further the source should maximize lift-off process by reducing stray and secondary electrons. Uniformity of metal thickness across a 150-mm diameter wafer should be 5% or better. A high voltage discharge hook should be provided for safe system maintenance. The deposition rate and thin film thickness should be monitored via multiple crystal sensors, e.g. one at mid-chamber for rate and one at substrate for thickness, and utilize a closed-loop film thickness controller.

F. The platen should provide rotation (variable, up to 20 rpm) and water cooling to limit substrate temperature for improved lift-off processing. A pneumatically-actuated substrate shutter must be included.

G. The system must be fully-automated via computer control. To avoid issues with computer or software malfunction, a standalone controller should provide equipment automation that is independent of the Windows software user interface. Fully automated, recipe-driven control of evaporation must be provided to include a graphical recipe builder with manufacturer provided stock recipes that can be edited with copy and saving functionality with unlimited recipes and user control with varying security levels. The recipes should allow for selected user input without affecting the overall recipe, e.g. update thin film thickness or rate. Software must run on a Windows-based computer with full HD touch-screen monitor and keyboard with touch pad. The computer must interface with controller to facilitate all vacuum, transfer, maintenance, and deposition process components. The software must contain visual display and control of system status messages, user log-in and log-out, operation mode, and system abort. It must have separate screens for display of full vacuum system and status, water flow switch status, and deposition parameters. The software must chart parameters (up to 10) with datalogging capability.

H. For maintenance, the system should include a complete second set of all shutters and shields as well as a common spares package to include seals, gaskets, substrate holder clips, crystal sensors, etc.

I. All components prior to assembly must be able to fit on a freight elevator with door dimensions of 6’ x 7’ (width x height) and car dimensions of 7.5’ x 8’ (depth x height). Additionally all components must fit through a laboratory door of 42” x 82” (width x height).

J. User manuals for all system components must be included in digital format.

2. Shipping: The probe station system and all accessories must be suitably crated/boxed and shipped to

NRL.

3. Installation and Training: The contractor shall provide on-site installation of the equipment and demonstrate that the system meets the required specifications. The contractor shall also provide on-site training at the time of the installation and demonstration for at least two NRL personnel.

4. Warranty and Support: The contractor shall offer the Government at least the same warranty terms, including offers of extended warranties, offered to the general public in customary commercial practice. The system must come with at least a 36 month warranty.