This inventor holds 7 USPTO granted patents. Top assignees: The Secretary of State for Defence in Her Britannic Majesty's Government, The Secretary for Defence in Her Britannic Majesty's Government of the, The Secretary of State for Defence in Her Britannic Majesty's Government of the United Kingdom of Great Britain and Northern Ireland. Active years: 1981-2002.
Location History:
- Hanley Swan, GB (1981)
- Worcestershire, GB (1994 - 2002)
Company Filing History:
5 out of 703 
1 out of 3 
1 out of 91 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.