C2QA_Sputter_RFI.pdf

Request for Information Sputter Deposition System for Quantum Device Fabrication

Overview The Co-design Center for Quantum Advantage (C2QA) at Brookhaven National Laboratory are planning to acquire a magnetron sputter deposition system to fabricate superconducting thin film materials that are relevant to quantum devices. It must provide a highly flexible platform for ultrahigh purity reactive and non-reactive sputtering, multi-source deposition, and precise process control.

1. General Requirement This RFI describes specifications for an ultrahigh vacuum (UHV) magnetron sputter deposition system for high-quality thin film synthesis of superconducting thin film materials that are relevant to quantum devices. The system must include the following major components: (1) a UHV stainless-steel sputtering chamber with base vacuum ≤ 2 × 10⁻⁹ Torr, configured for at least four (4) (and expandable to 8) magnetron sputtering sources in confocal geometry; (2) a fully integrated vacuum pumping system combining dry mechanical, turbomolecular, and cryogenic pumps, with bakeout and downstream throttle valve pressure control; (3) a substrate stage capable of continuous heating to 1000 °C, substrate rotation, Z-motion adjustment, and RF/DC biasing; (4) a sputtering atmosphere control system that includes at least three mass flow controlled gas lines with pneumatic isolation valves, supporting both inert and reactive sputtering; (5) an integrated load-lock chamber with independent pumping for rapid wafer transfer; and (6) a computer control system with integrated software for full process monitoring, logging, and automation. The vendor must provide onsite service covering system installation, commissioning, training, and warranty support.

2. Principal Configuration

2.1 Sputtering chamber, including

• A steel frame that supports the chamber, with integrated instrument rack;

• A cylindrical, electropolished stainless steel (SS) chamber with UHV construction, and configured in “sputter up” orientation;

• A hinged top flange, sealed with viton O-ring, that accommodates the substrate holder/heater;

• A bottom cluster flange that accommodates up to seven (7) 2-inch-target magnetron sputter sources, seven (7) source shutters and seven (7) VCR gas injection fittings in confocal geometry. The flange shall include a spare 8" CF port in the center for future expansion;

• Multiple CF ports on the chamber side wall, for installation of dedicated load-lock, vacuum pumps/gate valve, vacuum gauges, vent valve, and viewports with shutters. Besides the occupied ports, multiple spare ports shall be made available for future expansion, including the installation of RGA and RHEED. At the minimum, the extra ports shall include one (1) 10” CF, one (1) 6” CF, and four

(4) 2.75” CF;

• A removable SS chamber liner and viewport lighting;

• A customized main chamber bakeout system with the following features:

o Permanently mounted external resistive heat pads;

o Bake out System power controller with at least three (3) channel output with thermocouple and display;

o Custom thermal insulating jacket for main chamber;

2.2 Vacuum and pumping, including

• A dry mechanical backing pump with capacity ≥ 8 cfm;

• A turbomolecular pump (≥ 700 L/s) with controller, N2 purge, delayed vent, and interconnecting plumbing/hardware;

• A cryogenic pump with compressor, temperature sensor, roughing/regeneration valves, and interconnecting plumbing/hardware;

• A closed loop, automatic pressure-control/isolation throttle valve with full PID control;

• A vacuum gauge set that includes ion gauge, convectron gauge, and capacitance manometer, with integrated, full range gauge controller.

2.3 Gas handling system, including:

• At least two (2) gas lines (Ar and N2), independently controlled by mass flow controllers (MFCs), each equipped with independent pneumatic isolation valves and filters. Expandable to four (4);

• Substrate gas distributor and substrate gas ring for reactive deposition.

2.4 Magnetron sputtering sources and power supplies, including:

• At least four (4) installed UHV, confocal magnetron sources for 2-inch targets (expandable to 7), each equipped with integral isolation chimneys, independent UHV shutters and gas injection;

• The magnet array of each source shall be configurable for balanced, unbalanced, and magnetic material sputtering;

• At least three (3) DC generators (≥ 750 W, 1000 V/1 A) with integral switchbox and cable set;

• At least one (1) RF generator (≥ 300 W) with auto-matching networks.

2.5 Substrate handling, including:

• A substrate holder that is mounted to the chamber top flange and supports wafers up to 4" diameter, with motorized rotation and manual Z-motion;

• PID-controlled radiant heating up to 1000 °C, with water cooled reflector box that is compatible with O2 environment;

• RF/DC bias capability for pre-cleaning and in-process bias.

2.6 Load-lock, including:

• Integrated load-lock chamber with magnetic transfer system;

• Capable of transferring 4" wafers with susceptor;

• Independent pumping with turbopump (~80 L/s), rotary vane pump, and full range vacuum gauge;

• Manual gate valve isolation from main chamber.

2.7 Computer control system, including:

• A PC preinstalled with graphical user interface (GUI) for recipe-driven computer control;

• Interfaces with DC/RF power supplies, shutters, MFCs, heaters, substrate rotation, and vacuum valves;

• Real-time monitoring and logging of all process parameters;

• GUI-controlled pneumatic controls for all pneumatic devices, supporting at least 12 channels.

2.8 Power distribution and pump controls, including:

• Rack-mounted power distribution units for main system and pump controls;

• Independent mains breakers for each power distribution units;

• Interlocked and non-interlocked AC outlets for power supplies and pumps;

• Interlock inputs for water cooling, vacuum pumps, and safety systems;

• Integrated on/off breakers for turbomolecular and mechanical pumps.

2.9 Installation & services, including:

• Factory acceptance testing;

• System packing and delivery shipping;

• At least (2) days of on-site commissioning, installation, and training for system startup.

2.10 Warranty, including:

• A 2-year warranty covering all non-consumable parts of the system subjected to normal, proper usage;

• A 3-year warranty covering all non-consumable vendor-manufactured components.

3. Performance Requirements This section defines the required features and describes the performance specifications of the proposed sputter deposition system. The system must be a fully integrated UHV instrument with subsystems including the main deposition chamber, vacuum and pumping infrastructure, gas handling, magnetron sputtering sources with power supplies, substrate handling stage, load-lock, computer-based control, power distribution/pump control units, and essential accessories. The requirements below are minimum specifications; superior performance will be considered favorably.

3.1 Sputtering Chamber

3.1.1 Chamber design. The deposition chamber shall be constructed from electropolished SS, in a cylindrical geometry, with outer diameter about 14”. The chamber shall be UHV-compatible, with a base vacuum ≤ 2 × 10-9 Torr after bakeout.

3.1.2 Ports and expansion capability. The chamber shall be configured in a “sputter up” orientation, with a hinged, viton-sealed top flange for mounting the substrate holder/heater assembly. The bottom cluster flange shall accommodate up to seven (7) 2-inch confocal magnetron sputter sources, with independent shutters and VCR gas injection. A spare 8-inch CF port at the center shall allow future expansion. The chamber walls shall include multiple CF ports for load-lock integration, vacuum pumps, gauges, vent valves, viewports with shutters, and future expansion. At minimum, extra ports shall include one (1) 10-inch CF, one (1) 6-inch CF, and four (4) 2.75-inch CF.

3.1.3 Internal features and bakeout. The chamber shall include an internal SS liner and viewport lighting. A permanently mounted bakeout system must be provided, including external resistive heating pads, a multi-channel power controller with thermocouple monitoring, and a custom thermal insulating jacket.

3.2 Vacuum and Pumping

3.2.1 Pumping capacity. The system must employ a combination of dry scroll pump (≥ 8 cfm), turbomolecular pump (≥ 700 l/s), and cryopump (≥ 1500 l/s air, ≥ 4000 l/s water vapor). All pumps must be connected via interlocking plumbing. The system must achieve a rate of rise of at least 10 minutes (from 1 × 10-6 Torr to 1 × 10-5 Torr) and pump-down to ≤ 5 × 10-7 Torr within 35 minutes from clean, dry conditions after N2 vent.

3.2.2 Pressure control and gauging. The main chamber must include automatic throttle valve on an 8-inch CF for closed-loop PID control of process pressure. Upstream pressure control is not acceptable. Gauging must include an ion gauge, a convectron gauge, and a capacitance manometer, with integrated controller capable of reading three gauges simultaneously.

3.3 Gas Handling System

The gas handling system shall include at least two MFC-controlled gas lines: one Ar (100 sccm) and one N2 (20 sccm), each with independent pneumatic isolation valves and filters. The Ar line must be plumbed to at least one sputtering source with expandability to others; N2 must be delivered to the substrate stage via a substrate gas ring to minimize target poisoning. Expansion capacity for at least two additional MFCs (total of four) must be designed into the hardware and software.

3.4 Magnetron Sputtering Sources and Power Supplies

3.4.1 Sources. The system shall be capable of accommodating up to seven (7) 2-inch confocal UHV magnetron sources. At delivery, at least four (4) must be installed, each with pneumatic shutter, integral isolation chimney, and independent gas injection.

Sources must be bakeable to 200 °C with magnets left in place. Magnet arrays must be reconfigurable for balanced, unbalanced, and magnetic material sputtering. Guns must support up to 0.250-inch thick non-magnetic targets and up to 0.125”-thick magnetic targets. The con-focal deposition geometry shall achieve a thickness uniformity of ±1.5% for reactively deposited TiN, over a 4” diameter wafer (with exclusion of 5mm edge).

3.4.2 Power supplies. The system must include at least three (3) DC generators rated at ≥ 750 W, each capable of operating stably down to 1 W at 2 mTorr pressure.

Generators must provide simultaneous display of voltage, current, and power, kWh monitoring, and shutter actuation independent of the computer control. A 4-way automated DC switchbox must allow sharing of one generator among four sources. At least one (1) RF generator rated at ≥ 300 W with auto-matching network must be provided, capable of stable plasma at 3 W and 3 mTorr.

3.5 Substrate Handling

The substrate holder must support wafers up to 4 inches in diameter, with continuous motorized rotation (0–40 rpm). Z-motion of at least 4 inches must allow substrate-to-target spacing between 75–175 mm for direct deposition sources. The holder must enable uniform radiant heating to 1000 °C, with dual PID control for auto-switching between high/low ranges, ±1°C stability, and overtemperature protection. The holder must also include RF bias capability of at least 50 W during simultaneous heating, rotation, and deposition, with a dedicated 100 W RF supply and matching network.

3.6 Load-Lock

The load-lock shall be an aluminum chamber machined from a single billet, with its own 80 L/s turbopump, ≥ 4 cfm mechanical backing pump, and full-range vacuum gauge.

It must reach a base pressure of ≤ 5 × 10-7 Torr. A manual hand-crank actuator must permit user visibility through a viewport during substrate transfer, and the transfer arm must minimize sag.

3.7 Control System

The control system must have a graphical user interface (GUI) run on a PC supplied with the system. It must interface with up to five DC and four RF generators, the throttle valve, shutters, MFCs, substrate rotation, and heaters. Pneumatic actuation of at least eight shutters, four gas valves, and at least four spare devices must be supported.

The GUI must allow recipe-driven operation, process layer stacking, and remote recipe creation in line-by-line format. It must log and display all critical process parameters, including shutter positions, power outputs, plasma status, pressure, temperature, and gas flows. Automatic aborts must be triggered if plasma is lost or setpoints are not reached, with override capability to continue processing. Preventative maintenance reminders, diagnostics pages, and logging must be included.

3.8 Power Distribution and Pump Controls

The system must operate from single-phase 60 Hz, 120 VAC or 208 VAC circuits.

Water and vacuum interlocks must be hardwired to mains power, preventing unsafe operation of power supplies if interlocks are not satisfied. Rack-mounted distribution units must include separate breakers for vacuum pump control, with linked on/off operation of turbomolecular and mechanical pumps to simplify operation and ensure pump safety.

4. Vendor Questions

1. Can you provide a tool with specifications meeting or exceeding the request in this document?

2. What are the facility requirements (utilities, space, ceiling height, cooling water, electrical power, vibration isolation)?

3. Can you provide a site preparation guide?

4. What are the footprints of the proposed equipment?

5. Does the tool have electrical safety certification equivalent to UL/ETL/NRTL?

6. If certain requirements cannot be met, please indicate what can be achieved and demonstrated.

7. Would the system be manufactured in the United States? If not, what is the country of origin of the product?

8. What kind of warranty or servicing plan products do you offer?’

9. Could you please share a list of similar tools (no less than 10) that the vendor has installed in US/Worldwide research institution/facilities (specified in the list).