Solutions for Superconducting Qubits and Quantum Circuits

Superconducting TiN thin films deposited by plasma ALD with RF substrate bias

We've successfully deposited superconducting TiN by plasma ALD using bias to finely tune the film properties such as room temperature resistivity. Consequently, this has achieved a critical temperature of 3 K for a 90 nm film deposited at 250°C 

• T_c of ~3 K for 90 nm TiN
• Q_i internal quality factor is a key measure of resonator quality 
• Successful fabrication of microwave resonators with an internal quality factor of Qi > 10⁵ measured at ~250 mK, based on TiN deposited by plasma ALD in a FlexAL system (Coumou et al, 2013)
• RF-bias: variable to tune crystallinity, resistivity, film density and stress
• Further optimisation possible

Superconducting metals and metal nitrides etch: controlling surfaces to minimise noise and signal losses

Single-layer or stack etch resulting in:

• Smooth and residue-free sidewalls and surfaces
• Precise control of the etch profile
• Cluster to other modules for processing without vacuum breaks, such as ALD of tunnel barriers post metal-etch

Enabling these solutions are the FlexAL and PlasmaPro 100 deposition and etch systems, capable of producing small coupons through to 200 mm wafers, clusterable to increase throughput and avoid vacuum breaks.

Our PlasmaPro 100 platform enables high precision deposition and etching of a wide range of materials for quantum devices.

The FlexAL atomic layer deposition (ALD) system offers a broad range of optimised high-quality ALD processes for the fabrication of tunnel barriers and passivation layers for a variety of quantum devices, and enables the deposition of superconducting thin films with high critical temperature for TSVs, resonators and single-photon detectors.

Oxford Instruments have a strong history in providing state of the art solutions in this rapidly developing applications are a key enabler of quantum technologies beyond device fabrication solutions.