The reaction between high purity nickel (99.999%) and high purity tin (99.999%) was investigated in the temperature range of 232℃ - 330℃, at short periods of annealing (1 - 60 s). The reaction kinetic was studied us...The reaction between high purity nickel (99.999%) and high purity tin (99.999%) was investigated in the temperature range of 232℃ - 330℃, at short periods of annealing (1 - 60 s). The reaction kinetic was studied using cross-sectional scanning electron microscope (SEM) images. The intermetallic compound (IMC) growth was analyzed using the empirical power law and a time dependence in the range of 0.26 to 0.33 was found. The morphology of the IMC was investigated by SEM in the temperature range of 235℃ - 290℃, at annealing periods of 10 s, 30 s, and 60 s by selectively etching away the remaining elementary tin. The exposed IMC displays a change in morphology with increasing annealing temperature, demonstrating that the growth velocity of certain crystallographic orientations of the IMC is strongly influenced by the annealing temperature. Additionally, coarsening and crumbling of the IMC grains is observed, and will be discussed with respect to the responsible mechanisms.展开更多
In this investigation, the influence of a thin gold (Au) layer on the growth behavior of the intermetallic compound (IMC) in a Nickel-Tin-Solder (NiSn-Solder) was studied. The reaction kinetics was studied in the temp...In this investigation, the influence of a thin gold (Au) layer on the growth behavior of the intermetallic compound (IMC) in a Nickel-Tin-Solder (NiSn-Solder) was studied. The reaction kinetics was studied in the temperature range of 232℃ to 330℃ using cross-sectional scanning electron microscope (SEM) images. The kinetics of the reaction was determined using the empirical power law and the research showed that the introduction of an Au layer changes the reaction kinetics of the solder significantly. Furthermore, the change in reaction kinetics was accompanied by a change in morphology of the developing grains. The grain morphology of the IMC was studied for samples annealed at 290℃using cross-sectional and top-view samples and compared to Au free NiSn-Solder.展开更多
Photonic integrated circuits(PICs)represent a promising technology for the muchneeded medical devices of today.Their primary advantage lies in their ability to integrate multiple functions onto a single chip,thereby r...Photonic integrated circuits(PICs)represent a promising technology for the muchneeded medical devices of today.Their primary advantage lies in their ability to integrate multiple functions onto a single chip,thereby reducing the complexity,size,maintenance requirements,and costs.When applied to optical coherence tomography(OCT),the leading tool for state-of-the-art ophthalmic diagnosis,PICs have the potential to increase accessibility,especially in scenarios,where size,weight,or costs are limiting factors.In this paper,we present a PIC-based CMOS-compatible spectrometer for spectral domain OCT with an unprecedented level of integration.To achieve this,we co-integrated a 512-channel arrayed waveguide grating with electronics.We successfully addressed the challenge of establishing a connection from the optical waveguides to the photodiodes monolithically co-integrated on the chip with minimal losses achieving a coupling efficiency of 70%.With this fully integrated PIC-based spectrometer interfaced to a spectral domain OCT system,we reached a sensitivity of 92dB at an imaging speed of 55kHz,with a 6dB signal roll-off occurring at 2mm.We successfully applied this innovative technology to obtain 3D in vivo tomograms of zebrafish larvae and human skin.This ground-breaking fully integrated spectrometer represents a significant step towards a miniaturised,cost-effective,and maintenance-free OCT system.展开更多
文摘The reaction between high purity nickel (99.999%) and high purity tin (99.999%) was investigated in the temperature range of 232℃ - 330℃, at short periods of annealing (1 - 60 s). The reaction kinetic was studied using cross-sectional scanning electron microscope (SEM) images. The intermetallic compound (IMC) growth was analyzed using the empirical power law and a time dependence in the range of 0.26 to 0.33 was found. The morphology of the IMC was investigated by SEM in the temperature range of 235℃ - 290℃, at annealing periods of 10 s, 30 s, and 60 s by selectively etching away the remaining elementary tin. The exposed IMC displays a change in morphology with increasing annealing temperature, demonstrating that the growth velocity of certain crystallographic orientations of the IMC is strongly influenced by the annealing temperature. Additionally, coarsening and crumbling of the IMC grains is observed, and will be discussed with respect to the responsible mechanisms.
文摘In this investigation, the influence of a thin gold (Au) layer on the growth behavior of the intermetallic compound (IMC) in a Nickel-Tin-Solder (NiSn-Solder) was studied. The reaction kinetics was studied in the temperature range of 232℃ to 330℃ using cross-sectional scanning electron microscope (SEM) images. The kinetics of the reaction was determined using the empirical power law and the research showed that the introduction of an Au layer changes the reaction kinetics of the solder significantly. Furthermore, the change in reaction kinetics was accompanied by a change in morphology of the developing grains. The grain morphology of the IMC was studied for samples annealed at 290℃using cross-sectional and top-view samples and compared to Au free NiSn-Solder.
基金carried out in the framework of the project COHESION,No.848588funded by the Austrian Research Promotion Agency(FFG)support for the research of this work from funding from the European Union’s Horizon 2020 research and innovation program HandheldOCT(H2020,ICT 871312).
文摘Photonic integrated circuits(PICs)represent a promising technology for the muchneeded medical devices of today.Their primary advantage lies in their ability to integrate multiple functions onto a single chip,thereby reducing the complexity,size,maintenance requirements,and costs.When applied to optical coherence tomography(OCT),the leading tool for state-of-the-art ophthalmic diagnosis,PICs have the potential to increase accessibility,especially in scenarios,where size,weight,or costs are limiting factors.In this paper,we present a PIC-based CMOS-compatible spectrometer for spectral domain OCT with an unprecedented level of integration.To achieve this,we co-integrated a 512-channel arrayed waveguide grating with electronics.We successfully addressed the challenge of establishing a connection from the optical waveguides to the photodiodes monolithically co-integrated on the chip with minimal losses achieving a coupling efficiency of 70%.With this fully integrated PIC-based spectrometer interfaced to a spectral domain OCT system,we reached a sensitivity of 92dB at an imaging speed of 55kHz,with a 6dB signal roll-off occurring at 2mm.We successfully applied this innovative technology to obtain 3D in vivo tomograms of zebrafish larvae and human skin.This ground-breaking fully integrated spectrometer represents a significant step towards a miniaturised,cost-effective,and maintenance-free OCT system.
