Innos, a UK research and development company delivering expertise in silicon, MEMS and nanotechnologies, has announced its involvement in an ongoing EPSRC-funded project led by Queen Mary College London. The project is investigating the development of a new imaging technique — Scanning Photo-induced Impedance Microscopy (SPIM). With support from the company’s world-class clean room, SPIM measurements with good resolution and high sensitivity have been demonstrated.


The new SPIM imaging technique has potential in the investigation of the local dielectric properties of materials and biological specimen with good lateral resolution. Application areas include characterisation of smart materials and the development of new array technology for high throughput screening or sensing. It also can be used for investigation of cell-surface interactions, which are currently difficult to access with other techniques.

The best results obtained to date involved using thin silicon membranes from back etched silicon on insulator (SOI) wafers and thin, single crystalline silicon layers on silicon on sapphire (SOS) with a thin, thermally grown oxide; the latter even indicating the potential of submicrometer resolution.

Commenting on the close collaboration between the two companies, Dr. Steffi Krause from the department of materials at Queen Mary College said, “Innos has helped us to develop suitable semiconductor and insulator substrates that allow SPIM measurements with good resolution and high sensitivity.” She added, “We have improved resolution and sensitivity by reducing the insulator impedance and testing alternative semiconductor substrates. As part of the ongoing work we will be focusing on testing amorphous silicon, which will be grown at Innos.”