Helge Weman
Background and activities
My research area: Nanophotonic Materials and Devices
My research at NTNU focuses on synthesis and characterization of semiconductor nanowires for use in energy efficient light emitters and solar cells. Fabrication of nanowire/graphene devices is being explored by electron beam lithography, nanoimprint and focused ion beam techniques. Opto-electronic characterization using techniques such as low temperature photocurrent and electroluminescence is done in order to understand and utilize these nanowires in future photonic device applications. Since 2015 a strong focus is being made on AlGaN nanowire UV LEDs grown on graphene.
In 2010 I discovered and patented the growth of III-V semiconductor nanowires on graphene originally shown for GaAs nanowires, as schematically shown in this viral YouTube video https://www.youtube.com/watch?v=3wLOXHRVVwQ
I am the inventor or co-inventor of 14 different patent families with over 50 patents granted worldwide.
I am the Founder and Chief Scientific Officer of CrayoNano AS http://crayonano.com (founded in 2012) who are now developing germicidal (UVC) LEDs using AlGaN nanowires grown on graphene for use in water, air and surface disinfection applications.
I am an elected member of the Norwegian Academy of Technical Sciences (NTVA) since 2010.
Scientific, academic and artistic work
A selection of recent journal publications, artistic productions, books, including book and report excerpts. See all publications in the database
Journal publications
- (2020) The influence of AlN buffer layer on the growth of self-assembled GaN nanocolumns on graphene. Scientific Reports. vol. 10 (853).
- (2019) GaN/AlGaN nanocolumn ultraviolet light-emitting diode using double-Layer graphene as substrate and transparent electrode. Nano letters (Print). vol. 19 (3).
- (2019) Single GaAs Nanowire/Graphene Hybrid Devices Fabricated by a Position-Controlled Microtransfer and an Imprinting Technique for an Embedded Structure. ACS Applied Materials & Interfaces. vol. 11 (14).
- (2019) Epitaxially grown III-arsenide-antimonide nanowires for optoelectronic applications. Nanotechnology. vol. 30 (29).
- (2019) AlGaN Nanowires Grown on SiO2/Si (100) Using Graphene as a Buffer Layer. Crystal Growth & Design. vol. 19 (10).
- (2018) Vertical GaN nanocolumns grown on graphene intermediated with a thin AlN buffer layer. Nanotechnology. vol. 30:049601.
- (2018) Selective area growth of AlGaN nanopyramid arrays on graphene by metal-organic vapor phase epitaxy. Applied Physics Letters. vol. 133 (26).
- (2018) Single-mode near-infrared lasing in a GaAsSb-based nanowire superlattice at room temperature. Nano letters (Print). vol. 18 (4).
- (2018) Direct Growth of AlGaN Nanorod LEDs on Graphene-Covered Si. Materials. vol. 11.
- (2017) Determination of GaAs zinc blende/wurtzite band offsets utilizing GaAs nanowires with an axial GaAsSb insert. Journal of Applied Physics. vol. 122 (24).
- (2017) Growth study of self-assembled GaN nanocolumns on silica glass by plasma assisted molecular beam epitaxy. Journal of Crystal Growth. vol. 480.
- (2017) Evaluating focused ion beam patterning for position-controlled nanowire growth using computer vision. Journal of Physics: Conference Series. vol. 902 (1).
- (2017) Chemical vapor deposition of graphene on platinum: Growth and substrate interaction. Carbon. vol. 111.
- (2016) Effect of V/III ratio on the structural and optical properties of self-catalysed GaAs nanowires. Nanotechnology. vol. 27 (44).
- (2016) In situ electronic probing of semiconducting nanowires in an electron microscope. Journal of Microscopy. vol. 262 (2).
- (2016) In situ heat-induced replacement of GaAs Nanowires with Au. Nano letters (Print). vol. 16 (5).
- (2016) Vertically Oriented Growth of GaN Nanorods on Si Using Graphene as an Atomically Thin Buffer Layer. Nano letters (Print). vol. 16 (6).
- (2016) Low frequency noise in single GaAsSb nanowires with self-induced compositional gradients. Nanotechnology. vol. 27 (38).
- (2016) Fabrication of Si(111) crystalline thin film on graphene by aluminum-induced crystallization. Applied Physics Letters. vol. 108.
- (2016) New Insights into the Origins of Sb-Induced Effects on Self-Catalyzed GaAsSb Nanowire Arrays. Nano letters (Print). vol. 16 (2).