用阴极发光观察材料中的杂质和缺陷

Dr. David Lindgren is an experimentalist with a solid theoretical background currently living in Sweden and working at Hexagem AB. His main expertise lies within characterizing the optical properties of semiconductors for a wide range of applications, through design and execution of experiment and advanced analysis.

Dr. Lindgren has worked previously as a senior engineer at Sol Voltaics, a start-up which produced solar cells out of nanowires with a new technique called Aerotaxy. His PhD was dedicated to optical characterization of III-V semiconductors for different components like LEDs and solar cells. It allowed him to expertly manage cathodoluminescence and photoluminescence systems and perform fundamental research looking at impurities of materials and defects that could be related to malfunction of components.

When working at Sol Voltaics, Dr. Lindgren and his team continuously used the SPARC Compact system to study different materials and phenomena. The materials of interest were Gallium Arsenide nanowires grown by Aerotaxy and MOCVD, with and without a passivating Aluminum Gallium Arsenide shell.

With SPARC Compact system we did several hundred CL measurements per week and really managed to develop methods for quick analysis of the data.

Dr. Lindgren acknowledges that the spatial resolution achieved with cathodoluminescence was particularly beneficial, especially because the hyperspectral mode of the SPARC Compact system was used, but occasionally complementary measurements by additional techniques were needed, such as TEM, XRD and low-temperature PL.