Public Funding for Sci-Tron Limited

Use of III-V compound semiconductors (CS) in a range of applications including high speed/power electronics, lasers, power amplifiers for mobile phones, RF/microwave, space-tech and photonics is on rise due to their superior light receiving/emitting functionality, very high frequency signal generation capacity, at-least 100-times more power than their silicon counterparts, high-speed signal processing, low voltage operation and magnetic/heat sensitivity. CS patterning utilises following two major lithographic tools followed by an etch step (where the written pattern is transferred into the CS substrate): * Photolithography(PL)--widely used, working at 365, 248 and 193nm for production of Integrated circuits (ICs); shorter wavelengths are only available for largest manufacturers (e.g. Intel/Samsung/TSMC/Global Foundries) but a large industry depends on fabrication at 365nm. * Electron Beam Lithography(EBL)--used for key steps in electronics (e.g. mask-making) and more widely in smaller foundries to produce micro/nano-structures III-V CS hardness presents significant technical challenges to etch thin deep features at high resolution (<100nm) and to etch through multilayer structures required for high-end future applications such as micro Lasers/LEDs, nanoscale spectrometers, sensors and wireless communications. State-of-the-art solutions include positive (ZEP520A-chloroacrylate/styrene copolymer) and negative (HSQ-hydrogensilsesquixoane) tone solutions. ZEP520A gives an etch selectivity of 5:1\. which is insufficient to write deep thin structures, or to etch through multilayers of CS. HSQ can achieve etch-sensitivity of 7:1 but has drawbacks of requiring skilled chemist/lithographer, limited shelf-life due to degradation over time and damage to CS surface through adhesion. Building upon outputs of Innovate-UK project (\#104747) and our expertise in making Heterometallic-Ring-Complexes as building blocks, we have already developed a lab-scale manufacturing process with a throughput of 0.5litres/day of resists which can be used with silicon nanostructures (9nm wide and 330nm high). Driven by global end-user manufacturers' (Jet Propulsion Laboratory, CST, Microsemi, NASA, Ryan Briggs, Hughes Research Labs) demand of etching thin deep features at higher resolution and to be able to etch through multilayer structures; we can produce proof-of-principle quantities of (ca. 0.3litres) high-etch resists to be used with CS. This 18months industrial-research project aims to design and build a flexible manufacturing facility producing high-etch resists (capacity=50 litres/annum @ production cost of <£400/litre) to enable fabrication of thinner deeper structures and multilayer structures of differing CS in many fewer write-develop-etch steps. Project success will generate a catalogue of resists, made in small batches by Sci-Tron but all ready for contract manufacture. Sci-Resists will offer competitive advantages to all adopters and help growth of UK's vital high-tech sector.

"For the last 40 years, the semiconductor industry has been producing increasingly powerful, power efficient, and affordable electronic devices mainly due to innovative developments in lithography (semiconductor patterning) equipment and materials. Improvements in photolithography (PL) and electron beam lithography (EBL) equipments have delivered progressively higher resolution images with every generation. As part of the lithography process, 'resists' are used as materials that physically record exposure patterns on a silicon wafer as imaged from a mask. To realize the improvements in photolithography equipments, resist performance must keep pace. Sci-Tron Ltd are developing resists which can be tailored to meet the challenges presented by all forms of lithography. This Innovate UK proposal is to build our capacity to supply the PL and EBL markets. The testing we have performed suggests we have products that can produce a major competitive advantage to many UK companies which use lithography. Developing the best business model for this diverse market-place will be a key target of this project. Currently we can produce resists in laboratory conditions at a gram scale. During this project, we will develop a flexible manufacturing process which aims to produce a catalogue of resists to satisfy a large number of potential end-users that will have diverse needs, diverse scale and who may use either EBL or PL as a writing tool. For some resists we will need to scale-up and maintain low cost; for other bespoke resists small scale will be sufficient, but with the capacity to produce on demand and with a high profit on small amounts of material. In partnership with the University of Manchester (UoM), this 18 months industrial research project will help us developing manufacturing capability which provides flexibility to switch between different resists while maintaining the required quality control. Key project activities include; 1) design and build a flexible manufacturing facility capable of a 20kg per annum throughput of resist, and capable of switching between different resist formulations to meet specific end-user requirements, 2) complete application specific testing with key partners to develop resist materials to TRL6, and 3) develop a complete business plan detailing the resources, distribution and supply chain required, and the value proposition, team composition and expected financial outcomes for Sci-Tron."