Impact case study database

that has occurred **

The impact arises from the translation of our semiconductor research and expertise to Teledyne UK Ltd (formerly Teledyne e2v Ltd and e2v Technologies plc prior to March 2017 [a]; the company is owned by Teledyne Technologies Incorporated) to advance their activities in the design and manufacture of RF/microwave component and subsystems, and digital imaging sensors, primarily serving medical, defence and space markets. Teledyne UK Ltd has global sales of GBP150M per annum and employs approximately 2000 people [d].

Teledyne UK Ltd took a strategic business decision to relocate their semiconductor fabrication facilities from Lincoln to the SoPA (UoN), and in 2010 established the ‘The Teledyne Semiconductor Technology Centre’ [b] (TSTC). This embedded facility is a state-of-the-art cleanroom (102 m²) for III-V semiconductor manufacturing with a research and development capability. The TSTC is leased, fully staffed and funded by Teledyne UK Ltd [c], and has continued to operate and evolve throughout the assessment period.

Our expertise in the growth and modelling of devices with negative differential conductance was a key factor in their decision to re-locate as confirmed by Teledyne UK Ltd [d], and they particularly value the informal interactions between our researchers and company employees which is realised through this co-location ‘ The Teledyne Semiconductor Technology Centre provides a state-of-the-art semiconductor cleanroom in the University’s School of Physics and Astronomy. Placements of our facilities, directly in the School of Physics and Astronomy, allows us access to world leading research facilities in addition to our own, but moreover, the open informal access to the researchers themselves. It is this informal knowledge transfer that we have found particularly beneficial…’’ [d].

Teledyne UK Ltd’s manufacturing activity draws heavily on our research infrastructure. Our partnership with the company is based on collaboration and service agreements to cover knowledge transfer and intellectual property [b], the lease of cleanroom and office space [c], and access to SoPA facilities (workshops, a nanofabrication cleanroom, and plasma deposition equipment) which are used in their manufacturing processes. Subsequently, we have worked with Teledyne UK to translate our research on new device concepts into their products, thus influencing their investment plans and technology roadmaps [d].

We describe below two types of impact: firstly, how research has supported and sustained the manufacture of commercial microwave devices; and, secondly, collaborative projects which have led Teledyne UK Ltd to re-direct their research strategy.

1. Manufacture of microwave oscillators and receiver diodes

Microwave oscillators and receiver devices are a key part of Teledyne UK’s portfolio and are now manufactured in the embedded TSTC using III-V semiconductor heterostructures grown by ECMN researchers in the SoPA using molecular beam epitaxy, and through access to our clean-room facilities (in addition to those in the TSTC). These devices include cutting-edge Teledyne Gunn diodes with an enhanced AlAs emitter-booster, and Schottky receiver diodes. Both types of device are manufactured from heterostructures which require highly precise levels, and spatial control, of doping and (GaAl)As alloy composition. Building on the expertise gained in the growth of heterostructures used in our experimental studies of negative differential conductance [1,2,6,7], researchers in the SoPA have been able to meet the demanding Teledyne UK specifications; in the REF2021 assessment period we have supplied 2” wafers for the fabrication of Gunn diodes (10 wafers) and Schottky diodes (12 wafers), all of which were grown by Campion. The fabrication of Schottky diodes requires additional processing steps (PECVD oxide deposition and ICP dry etching) using our facilities which were established in support of our nitride semiconductor programme [4]. Our facilities are also used for a deep etch process step in the fabrication of Gunn diodes. The use of our advanced ICP dry etching has also improved the yield of the beam-lead (a low induction contacting methodology) diode production process.

Teledyne Gunn and Schottky diodes are high frequency (> 100 GHz) sources and receivers and exemplify an industry challenge addressed by our joint research effort; no devices offering the performance levels demanded by Teledyne customers are made anywhere else in the world. Sales of these specialist diodes manufactured in the TSTC amount to GBP5.5M over the REF2021 assessment period [ d]. The availability of these devices as components of larger systems provides further added value as stated by Teledyne UK Ltd [d] ‘ Recently a major multinational defence company has committed to millimetre wave sensing programmes which will see our Schottky diodes utilised in their new system builds for at least the next ten years, whilst a UK based security system manufacturer has designed our Gunn diodes into all of their current and next generation scanner products’, and, specifically ‘these diode applications directly exploit technology that comes out of the collaboration, and underpin multi-million-pound exports for our customers.’, thus providing additional impact in the security and defence sectors.

4.2 Technology transfer of new device concepts

The formation of the TSTC has also led to translation of our research, as recognised by Teledyne UK: “ The research at Nottingham has guided strategic thinking at site and national levels, with regard to technology and product road maps including the company’s STRategic Action Plan (STRAP). Of particular importance is our joint ability to provide new and novel compound semiconductor technology and components”. [d] Through discussions between their engineers/managers and researchers in the SoPA, Teledyne UK Ltd have also developed a roadmap for several new products. These routes to technology transfer have been enabled through a HERMES Fellowship, Knowledge Transfer Secondments (KTS), and a Knowledge Transfer Partnership (KTP) [I-IV], Industrial-CASE (I-CASE) and EPSRC PhD studentships [V,VI], and research which is fully funded by the company [VII]. We describe below two examples of translation which have influenced the company’s strategic plans.

4.2.1 Superlattice electron devices The negative differential conductance in superlattice heterostructure devices reported by SoPA researchers [2,6,7] offers the prospect of high-frequency (THz) oscillators with tailored properties which have the potential to improve and extend Teledyne UK’s products. A series of collaborative awards [I-IV], and direct funding from the company [VII], [d] supported the development of superlattice electron devices for millimetre wave applications [II]. Subsequently, in 2017, Teledyne UK Ltd started to fabricate demonstrator sub-THz devices using heterostructure layer designs developed by Professor Patanè and co-workers [e]; two wafers were grown by MBE and supplied to Teledyne UK. These superlattice devices will be used as mm-wave multipliers and sub-harmonic mixers, components for security products such as THz-imaging systems. A key aspect of this project was the " technology transfer of the device fabrication process and the heterostructure design” of beam-lead superlattice electron devices from the SoPA team to the Teledyne UK Ltd team [d].

4.2.2 Receiver protectors: Yield improvements and new simulation methods Receiver protector diodes are a key component in Teledyne UK Ltd’s microwave systems. Advanced theoretical modelling techniques (developed by Fromhold **[1,6,7]**) and detailed data analysis have been applied to characterise and improve the performance and yield of the PIN diodes used in the receiver protectors with support from two collaborative awards [III, IV]. Teledyne UK Ltd state ‘ The KTP found ways to improve the yield of the production process improving the profitability of the existing receiver protector product line in Teledyne. The market for such systems is worth c.£5 M p.a. to Teledyne Lincoln Microwave, with a predicted financial impact of increase profits by 10-20% per year.’ [d].

In a second phase of this work, which concerns the emerging requirements for next-generation receiver protector products, the need was identified for improved predictive modelling that allows engineers to design microwave systems with performance characteristics significantly beyond the capabilities of current design approaches. This was highlighted by Teledyne as a shortcoming in existing industry standard simulation tools. In 2016, an I-CASE studentship sponsored by the Defence Science and Technology Laboratory (DSTL) in partnership with Teledyne UK Ltd [V] was established with the aim of improving the advanced computer simulation of high-frequency electronic components for radar receiver protectors. Researchers [V, VI] in the SoPA, and UoN Electronic Engineering, have developed Unstructured Transmission Line Modelling codes to improve the modelling accuracy and speed of receiver protector simulations. Teledyne UK Ltd state ‘ This novel simulation work has assisted our strategic decision making, giving us the confidence to feature next-generation receiver protectors as a key strand of our technology roadmap.’ [d].

In summary, our research in semiconductor physics has influenced the Teledyne UK roadmap (see discussion of STRAP **[d]**) and underpinned the sales (GBP5.5M) of components fabricated in the TSTC. Teledyne UK Ltd confirm the strategic importance of the link with the SoPA “When we entered into the partnership with the School of Physics and Astronomy, University of Nottingham, we knew we had started something with great potential. The result is that we now have a well-established, unique capability in the UK which is viewed by many as a model that delivers products for customers and also supports and fosters world-leading complementary research that exploits cutting edge physics for challenging applications in growing markets. The success of the collaboration has exceeded expectations and reinforced Teledyne’s position at the forefront of UK discrete compound semiconductor device manufacture.” [d].