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Kelvin probe force microscopy (KPFM) is used to investigate the electrostatic force between a conductive probe and doped semiconductors. The observed frequency dependence of the probed KPFM bias is strongly related to sample‐specific intrinsic local electric fields. Equilibrium drift and diffusion of excess charge carriers at low operation frequencies influence the characteristics of the asymmetric electric dipole in the surface region of the investigated semiconductors during the KPFM measurement. The sample‐specific KPFM background signal does not influence the frequency‐dependent lateral variation of the electrical signal. The KPFM bias probed on doped semiconductor nanostructures with high or small enough operation frequencies allows for quantitative dopant profiling or investigation of diffusion processes in internal electric fields, respectively.

InAs with an extremely high electron mobility (up to 40,000 cm(2)/V s) seems to be the most suitable candidate for better electronic devices performance. Here we present a synthesis of inverted crystalline InAs nanopyramids (NPs) in silicon using a combined hot ion implantation and millisecond flash lamp annealing techniques. Conventional selective etching was used to form the InAs/Si heterojunction. The current-voltage measurement confirms the heterojunction diode formation with the ideality factor of η = 4.6. Kelvin probe force microscopy measurements indicate a type-II band alignment of n-type InAs NPs on p-type silicon. The main advantage of our method is its integration with large-scale silicon technology, which also allows applying it for Si-based electronic devices.

We report the fabrication of Ge:Mn ferromagnetic semiconductors by Mn-ion implantation into Ge followed by pulsed laser annealing. Benefiting from the short time annealing, the hole concentration in Mn-implanted Ge has been increased by two orders of magnitude from 10 18 to over 10 20 cm −3 . Likely due to the high hole concentration, we observe that the longitudinal and Hall resistances exhibit the same hysteresis as the magnetization, which is usually considered as a sign of carrier-mediated ferromagnetism.

Transformation‐induced plasticity (TRIP) steels are known for their outstanding strength and their excellent deformation properties, which are necessary for the improvement of occupant safety elements in air, rail and motor vehicles. One precondition for the realization of the TRIP effect is the creation of a metastable austenitic microstructure through the addition of a number of alloying elements. The great affinity of some alloying elements for oxygen implies the formation of highly stable oxides during thermal processing. In the current study, an extrusion process (derived from the processing of ceramics) with subsequent debinding and pressureless sintering is used to manufacture compact strands from prealloyed and gas‐atomized 17Cr7Mn6Ni TRIP steel powder. The influence of both the debinding temperature and sintering atmosphere on the oxide particle content in the final bulk product are investigated by X‐ray diffraction (XRD) analysis and quantitative metallography. Furthermore, X‐ray photoelectron spectroscopy (XPS) analysis in association with temperature‐programmed reduction (TPR) experiments, thermogravimetric (TG) measurements and mass/infrared spectroscopy (MS/IRS) serve to monitor the changes in the steel powder surface composition and the effectiveness of hydrogen as a reducing agent.

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Material-and energy-saving lightweight constructions are of particular interest to the industry since decades, especially for vehicle and aircraft production. One of the ways of reducing the weight in components is to replace a solid matrix by periodically recurring cell or truss structure. Cellular materials such as metallic foams, truss, or honeycomb structures are characterized by high specific energy absorption and rigidness. Due to their high specific stiffness and compressive strength, square honeycomb structures are well suited for energy dissipating stiffeners, such as sandwich panels and bumpers. [1][2][3] However, the production of honeycomb structures using conventional manufacturing methods is very complex. Metallic square-celled honeycomb structures are often produced in two ways: either slotted metal strips are inserted into each other and joined together by soldering, or they are produced by metal extrusion using complex dies. [4,5] Another recently developed technology is the extrusion of powders with a binder and subsequent debinding and sintering. [6,7] In contrast, additive manufacturing (AM) allows producing most of the complex lightweight structures in a single manufacturing step. All of the AM methods are based on the computer-aided design (CAD), taking a model of a component and building it up layer by layer. One of the most advanced AM methods for the fabrication of metallic components is the electron beam powder-bed fusion (EB-PBF) technology, which is called electron beam melting (EBM) in the following. This process belongs to the group of powderbed AM technologies in which powder particles are fused layer by layer. [8,9] The EBM process is somewhat similar to the widely used selective laser melting (SLM) process, although there are principal differences between laser and electron beam. [10] The microstructure of EBM-manufactured materials is often characterized by columnar and epitaxial grain morphology. Continuous melt crystallization through the multiple layers results in the formation of a strong texture and anisotropy. [8,[11][12][13] This phenomenon can even be utilized to produce single crystalline superalloys by adapting EBM scanning strategy. [14,15] However, in case of materials which can undergo phase transformation in the solid state during cooling (Ti-6Al-4V, Ti-6Al-4V doped with Cu or La, titanium aluminide, and so on), the mentioned columnar and textured structure can be avoided.