Applications

A Scanning Electron Microscope (SEM) is a powerful microscope that uses a high-energy electron beam to scan the surface of a specimen, capturing signals emitted or scattered by electrons to generate high-resolution images of the specimen surface. SEM can magnify images by thousands to tens of thousands of times, revealing a microscopic world that is imperceptible to the naked eye.   Under the CIQTEK Scanning Electron Microscope, we can observe the fine textile structure of lizard skin cells, which allows for a visual examination of the structural characteristics of crystalline plates in the skin, such as their size, length, and arrangement. These images not only provide a visual feast but also offer crucial clues for scientists to interpret material properties, disease mechanisms, and biological tissue functions. Figures1. Ultrastructure of lizard skin/30 kV/STEM In the field of electron science, SEM helps engineers examine tiny solder joints and conductors on circuit boards in detail to ensure the precision and reliability of technology. In materials science, SEM can be used to analyze fracture surfaces of metal alloys, optimizing industrial design and processing technology. In biological applications, SEM can display the surface structure of bacteria and even observe interactions between viruses and host cells.   Figures2. SEM3200/Ordinary chip2/10 kV/ETD SEM is not just a machine; it is more like a meticulous detective that helps us uncover the microscopic secrets in nature and man-made objects, providing strong support for scientific research and technological innovation. Through SEM, scientists can better understand the nature of materials, the structure of biological tissues, and the essence of various complex phenomena, pushing the boundaries of our knowledge forward.   Common Misconceptions about SEM:   1. Are SEM images in true colors?   SEM produces black and white images because they result from the interaction of electrons with the specimen, not from light waves. The colored SEM images typically seen are post-processed using digital coloring techniques to distinguish different structures or enhance visual effects.   2. Is higher magnification always better?   While SEM can provide extremely high magnification, not all research requires maximum magnification. Excessive magnification beyond the specimen's feature scale not only increases scanning time but may also lead to an increase in irrelevant information.   3. Can SEM see atoms?   Although SEM offers high resolution, it often cannot reach the level of observing individual atoms. To observe structures at the atomic scale, transmission electron microscopes (TEM) or scanning tunneling microscopes (STM) are typically needed.   4. Is SEM only suitable for solid and lifeless specimens?   While SEM was initially designed for solid materials, modern techniques allow observation of biological specimens as w...

Electron Backscatter Diffraction (EBSD) is a widely used microscopy technique in material science. It analyzes the angles and phase differences of the backscattered electrons produced when a sample interacts with a high-energy electron beam to determine key characteristics such as crystal structure and grain orientation. Compared to a traditional Scanning Electron Microscope (SEM), EBSD provides higher spatial resolution and can obtain crystallographic data at the sub-micrometer level, offering unprecedented details for analyzing material microstructures.   Characteristics of the EBSD Technique   EBSD combines the microanalysis capabilities of Transmission Electron Microscope (TEM) and the large-area statistical analysis capabilities of X-ray diffraction. EBSD is known for its high-precision crystal structure analysis, fast data processing, simple sample preparation process, and the ability to combine crystallographic information with microstructural morphology in material science research. SEM equipped with an EBSD system not only provides micro-morphology and composition information but also enables microscopic orientation analysis, greatly facilitating the work of researchers.   Application of EBSD in SEM   In SEM, when an electron beam interacts with the sample, various effects are generated, including the diffraction of electrons on regularly arranged crystal lattice planes. These diffractions form a "Kikuchi pattern," which not only contains information about the symmetry of the crystal system but also directly corresponds to the angle between crystal planes and crystallographic axes, with a direct relationship to the crystal system type and lattice parameters. This data can be used to identify crystal phases using the EBSD technique, and for known crystal phases, the orientation of the Kikuchi pattern directly corresponds to the orientation of the crystal.   EBSD System Components   To perform EBSD analysis, a set of equipment including a Scanning Electron Microscope and an EBSD system is required. The core of the system is the SEM, which produces a high-energy electron beam and focuses it on the sample surface. The hardware part of the EBSD system usually includes a sensitive CCD camera and an image processing system. The CCD camera is used to capture the backscattered electron images, and the image processing system is used to perform pattern averaging and background subtraction to extract clear Kikuchi patterns.   Operation of the EBSD Detector   Obtaining EBSD Kikuchi patterns in SEM is relatively simple. The sample is tilted at a high angle relative to the incident electron beam to enhance the backscattered signal, which is then received by a fluorescent screen connected to a CCD camera. The EBSD can be observed directly or after amplification and storage of the images. Software programs can calibrate the patterns to obtain crystallographic information. Modern EBSD systems can achieve ...

Focused Ion Beam (FIB) technology has become an essential part of modern technological advancements, particularly in semiconductor manufacturing and nanofabrication. While FIB technology is well-known, its history and development are not widely known. Focused Ion Beam (FIB) is a micro-cutting instrument that uses electromagnetic lenses to focus an ion beam into a very small area. FIB involves accelerating ions from an ion source (most FIBs use Ga, but some devices have He and Ne ion sources) and then focusing the beam onto the surface of the sample. CIQTEK DB550 Focused Ion Beam Scanning Electron Microscope (FIB-SEM)    Origin of FIB Technology   Since the 20th century, nanotechnology has rapidly developed as an emerging field in science and technology. Currently, nanotechnology represents one of the forefront areas of scientific and technological advancement and has significant implications for economic and social development as a national strategy. Nanostructures have unique properties due to their structural units approaching the coherence length of electrons and the wavelength of light, leading to surface and interfacial effects, size effects, and quantum size effects. They exhibit many novel characteristics in electronics, magnetism, optics, and mechanics, and hold enormous potential in high-performance device applications. The development of novel nanoscale structures and devices requires the advancement of precise, multidimensional, and stable micro-nanofabrication techniques. Micro-nanofabrication processes are extensive and commonly involve techniques such as ion implantation, photolithography, etching, and thin film deposition. In recent years, with the trend of miniaturization in modern manufacturing processes, Focused Ion Beam (FIB) technology has increasingly been applied in fabricating micro-nano structures in various fields, becoming an indispensable and important technique in micro-nanofabrication.   FIB technology is developed based on conventional ion beam and focused electron beam systems and is essentially the same. Compared to electron beams, FIB scans the sample surface using an ion beam generated by an ion source after acceleration and focusing. Since ions have much greater mass than electrons, even the lightest ions, such as H+ ions, are more than 1800 times the mass of electrons. This enables the ion beam to not only achieve imaging and exposure capabilities similar to electron beams but also utilize the ion's heavy mass to sputter atoms from solid surfaces, making it a direct processing tool. FIB can also induce atoms to deposit onto the sample material surface by combining with chemical gases. Therefore, FIB is a widely applicable tool in micro-nanofabrication.   Development of Ion Sources   In the development of FIB technology, the advancement of high-brightness ion sources has been crucial. Early gas ion sources and Liquid Metal Ion Sources (LMIS) laid the foundation for FIB technolo...

Creating a perfect image requires a combination of theoretical knowledge and practical experience, and a balance between many factors. This process may encounter some challenging issues in the use of the Electron Microscope.    Astigmatism   Astigmatism is one of the most difficult corrections to make in an image and requires practice. The middle image in the following figure is a correctly focused image after astigmatism correction. The left and right images are examples of poor astigmatism correction, resulting in stretched stripes in the image.   To achieve precise imaging, the cross-section of the Electron Beam (probe) should be circular when it reaches the specimen. The cross-section of the probe may become distorted, forming an elliptical shape. This can be caused by a series of factors, such as machining accuracy and defects in the magnetic pole piece or copper winding in the casting of the ferromagnetic coil. This deformation is called vignetting and can result in difficulties in focusing.   Severe astigmatism is one of the most difficult corrections to make in an image and requires practice. The middle image in the following figure is a correctly focused image after astigmatism correction. The left and right images are examples of poor astigmatism correction, resulting in stretched stripes in the image. can manifest as "stripes" in the X direction in the image. As the image transitions from under-focus to over-focus, the stripes will change to the Y direction. When the focus is precise, the stripes disappear, and proper focusing can be achieved if the spot size is appropriate.     When magnified around 10,000 times, if there are no stripes in either direction when the objective is adjusted to under-focus or over-focus, it is generally considered that there is no astigmatism in the image. Astigmatism is usually negligible in images below 1000 times magnification.   The best approach to correct vignetting is to set the X and Y vignetter offsets to zero (i.e., no astigmatism correction) and then focus the specimen as finely as possible. Then adjust the X or Y astigmatism control (cannot be adjusted simultaneously) to obtain the best image and refocus.   Edge Effects   Edge effects occur due to enhanced Electron Emission at the edges of the specimen. The edge effects are caused by the influence of morphology on the generation of secondary electrons and are also the reason for the image contour produced by the secondary electron detector. Electrons preferentially flow towards the edges and peaks and emit from the edges and peaks, resulting in lower signal intensity in areas obstructed by the detector, such as recesses. Backscattered electrons emitted from the region of the sample facing the detector also enhance the topographic contrast. Reducing the accelerating voltage can reduce edge effects.   Charging Effects   Uncontrolled discharge of electrons th...

Focused Ion Beam (FIB) is a microfabrication instrument that utilizes an electron lens to focus an ion beam into a very small size for precision cutting.   Working Principle   Liquid Metal Ion Source The ion source is the heart of the FIB system, and the accurate focusing of the ion beam begins with the emergence of liquid metal ion sources. The ions generated by liquid metal ion sources, mostly utilizing gallium (Ga) as the metal material, have high brightness and petite source sizes. Liquid metal ion sources are formed by the field-induced ion emission from a liquid metal surface under a strong electric field.   In the manufacturing process of the source, a tungsten wire with a diameter of about 0.5 mm is electrochemically etched to create a tungsten needle with a tip diameter of only 5-10 μm. The molten liquid metal is then adhered to the tip of the tungsten needle. Under the application of a strong electric field, the liquid metal forms a tiny tip (Taylor cone) due to the electric field force, with an electric field intensity of up to 10^10 V/m. Under such a high electric field, metal ions on the liquid surface evaporate into an ion beam through field evaporation. Despite the low ion current of only a few microamperes, the current density can reach approximately 106 A/cm2, and the brightness is about 20 μA/sr.   Focused Ion Beam System Focused ion beam technology utilizes electrostatic lenses to focus the ion beam into a very small size for microfabrication. Commercial FIB systems typically extract the particle beam from liquid metal ion sources. Gallium (Ga) is often used as a metal material due to its low melting point, low vapor pressure, and good oxidation resistance.   By applying an external electric field (Suppressor) to the top of the ion column, a small tip of the liquid metal or alloy can be formed. With the negative electric field (Extractor) applied, the tip of the metal or alloy is pulled out to generate the ion beam. The ion beam is then focused using electrostatic lenses, and the size of the ion beam can be controlled by an Automatic Variable Aperture (AVA) with an adjustable aperture. The desired ion species are selected using an E×B mass analyzer. Finally, the ion beam is focused on the specimen and scanned using an octupole deflector and an objective lens. The ion beam bombards the specimen, and the secondary electrons and ions generated are collected, imaged, or used for physical sputtering, cutting, or grinding.   Basic Functions   The basic functions of a focused ion beam microscope can be divided into four categories:   1. Precisional Cutting: Achieving cutting through the physical collision of ions. Widely used in Cross-Section processing and analysis of Integrated Circuits (ICs) and LCDs.   2. Selective Deposition: Decomposing organic metal vapor or gas-phase insulating material with the energy of the ion beam to locally deposit conductive or non-conductive ...

Definition and Characteristics of Crystals: Crystals are materials formed by the regular and periodic arrangement of particles (molecules, atoms, ions) in three-dimensional space. Crystals can be classified into single crystals and polycrystals. The formation of crystals involves the process of particles arranging themselves in a regular pattern. The regular arrangement of particles gives rise to a structured framework inside the crystal, making crystals solids with a specific lattice structure. Crystals exhibit regular geometric shapes, have fixed melting points, and display anisotropic properties such as mechanical strength, thermal conductivity, and thermal expansion. Crystals are abundant in nature, and most solid materials found in nature are crystals. Gases, liquids, and amorphous materials can also transform into crystals under suitable conditions. X-ray diffraction is commonly used to identify whether a material is a crystal or not. Melting Point and Distribution of Crystals:  The regular arrangement of atoms in crystals contributes to their fixed melting and solidification points, which is a distinguishing feature of crystals compared to amorphous materials. Crystals are diverse in morphology in nature, ranging from common substances like salt and sugar, minerals that make up the Earth's crust, to metals and semiconductor materials. Electron Microscopes and EBSD techniques can help understand the stability of crystals under different conditions and provide scientific insights for material selection and applications.   Single Crystals and Polycrystals: A single crystal consists of a continuous crystal lattice where the atomic arrangement remains consistent throughout the crystal, resulting in the anisotropic properties of the crystal. Single crystals are ideal for certain applications, such as silicon single crystals used as the foundation material for integrated circuits in the semiconductor industry.   Polycrystals, on the other hand, are composed of multiple grains with different orientations. Although the individual grains possess the same crystal lattice, their orientations are random, resulting in a polycrystal without macroscopic anisotropy. However, under specific processing conditions, the grains in polycrystals can align preferentially along a specific direction, forming a preferred orientation, which is known as crystallographic texture. Crystallographic texture can enhance the properties of materials in specific directions. For example, control of texture in metal processing can improve the material's ductility or strength. Analytical laboratories, such as the GoldTest Lab, provide precise analysis and testing of single crystals and polycrystals, offering reliable insights for material applications.   Importance of Crystal Orientation:  The analysis of crystal orientation is crucial for understanding material properties. Crystal orientation describes the relative position of crystal axes in t...

Recently, a research paper titled "Phononic modulation of spin-lattice relaxation in molecular qubit frameworks" by the research team led by Dr. Sun Lei from the School of Science at Westlake University was published in Nature Communications.   Figure 1: Hydrogen bonding network and phonon modulation of spin-lattice relaxation in MQFs   The team used CIQTEK pulsed Electron Paramagnetic Resonance (EPR) Spectroscopy X-band EPR100 and W-band EPR-W900 to characterize two molecular qubit framework materials containing semi-quinone radicals.   Figure 2: Spin dynamic properties of MgHOTP and TiHOTP   They discovered that hydrogen bonding networks in these materials led to decreased structural rigidity, resulting in sub-terahertz optical phonons, reduced Debye temperature, increased acoustic phonon density of states, and promoted spin-lattice relaxation. Deuterium substitution in the hydrogen bonding network further lowered the optical phonon frequencies and shortened the spin-lattice relaxation time.   Figure 3: Vibrational spectra of MgHOTP and TiHOTP   Based on these findings, the researchers proposed a molecular qubit framework design to control phonon dispersion precisely, suppress spin-lattice relaxation, and improve qubit performance. This achievement provides new insights and opportunities for solid-state integration and quantum information applications of molecular electron spin qubits.     Figure 4: Spin lattice relaxation mechanism of MgHOTP and TiHOTP Figure 5: Influence of deuterium substitution in the hydrogen bonding network on low-frequency optical phonons and spin-lattice relaxation in MgOTP   In summary, this study revealed that the structural rigidity of molecular qubit framework materials can be used to control phonon dispersion, suppress spin-lattice relaxation, and improve quantum coherence and the applicable temperature range. The research findings can potentially advance the solid-state integration and molecular quantum information technology of molecular electron spin qubits.

What is the Recrystallization Process?   Recrystallization is an important phenomenon in materials science that involves the microstructural recovery of material after plastic deformation. This process is crucial for understanding material properties and optimizing processing techniques.   Mechanisms and Classification of Recrystallization   Recrystallization processes are typically triggered by heat treatment or thermal deformation and involve the natural recovery of materials after the generation of defects during deformation. Defects such as dislocations and grain boundaries promote the reduction of system-free energy at high temperatures through dislocation rearrangement and annihilation, leading to the formation of new grain structures.   Recrystallization can be classified into static recrystallization (SRX) and dynamic recrystallization (DRX). SRX occurs during annealing processes, while DRX takes place during thermal deformation. Furthermore, recrystallization can be further subdivided based on specific mechanisms, such as continuous dynamic recrystallization (CDRX), discontinuous dynamic recrystallization (DDRX), geometric dynamic recrystallization (GDRX), and metadynamic recrystallization (MDRX). These classifications are not strictly defined, and researchers may have different interpretations.   Factors influencing recrystallization   The recrystallization process is influenced by various factors, including the stacking fault energy (γSFE), initial grain size, thermal processing conditions, and second-phase particles. The magnitude of the stacking fault energy determines the dislocation breakdown and mobility, thereby affecting the recrystallization rate. Smaller initial grain sizes and suitable thermal processing conditions, such as high temperature and low strain rates, facilitate recrystallization. Second-phase particles can significantly influence the recrystallization process by hindering grain boundary motion.   Application of imaging techniques   EBSD and TEM are two classic imaging techniques used in recrystallization studies. EBSD analyzes the distribution and percentage of recrystallized grains using the DefRex map, although resolution limitations may pose accuracy issues. TEM, on the other hand, provides a direct observation of material substructures, such as dislocations, offering a more intuitive perspective for recrystallization studies.   Application of EBSD in recrystallization studies   EBSD is used to determine whether grains have undergone recrystallization by observing grain boundaries. For example, in the DefRex maps of forged TNM alloys, grains surrounded by high-angle boundaries are typically considered recrystallized grains. This technique provides detailed information about grain orientations and grain boundary types, aiding in the understanding of microstructural changes during recrystallization.   BC+GB (grain boundary) map of forged TiAl alloy...