Location History:
- Hanley Swan, GB (1981)
- Worcestershire, GB (1994 - 2002)
Company Filing History:
5 out of 703 
1 out of 3 
1 out of 67 Years Active: 1981-2002
Title: Innovations of John M Keen
Introduction
John M Keen is a notable inventor based in Worcestershire, GB. He has made significant contributions to the field of semiconductor technology, holding a total of 7 patents. His work primarily focuses on the development of silicon quantum wires, which have promising applications in various technological domains.
Latest Patents
One of his latest patents involves a method of making semiconductor quantum wires. This method employs a semiconductor wafer as the starting material. The wafer is weakly doped p-type with a shallow heavily doped p layer for current flow uniformity purposes. It is anodised in 20% aqueous hydrofluoric acid to produce a layer that is microns thick with 70% porosity and good crystallinity. The layer is subsequently etched in concentrated hydrofluoric acid, which provides a slow etch rate. This etching process increases porosity to a level of 80% or above. At this level, pores overlap, and isolated quantum wires are expected to form with diameters less than or equal to 3 nm. The etched layer exhibits photoluminescence emission at photon energies well above the silicon bandgap (1.1 eV) and extends into the red region (1.6-2.0 eV) of the visible spectrum.
Career Highlights
Throughout his career, John M Keen has worked with various organizations, including the Secretary of State for Defence in Her Britannic Majesty's Government. His expertise in semiconductor technology has positioned him as a key figure in the advancement of innovative materials and methods.
Collaborations
John has collaborated with notable individuals in his field, including Leigh-Trevor Canham and Weng Y Leong. These collaborations have further enriched his research and development efforts.
Conclusion
John M Keen's contributions to the field of semiconductor technology, particularly in the area of silicon quantum wires, highlight his innovative spirit and dedication to advancing scientific knowledge. His patents and collaborations reflect a commitment to pushing the boundaries of technology.