A Winning Team: SEM + FIB, the "Golden Combination"   CIQTEK brings SEM and FIB together as a powerful team, providing critical support for PCB process optimization, reliability verification, and root cause determination of failures. SEM High-Resolution Imaging: The "Microscope" for Surface Details The SEM uses a high-resolution electron beam to capture crisp images of PCB surface morphology. It reveals solder pad plating, intermetallic compounds, micro-cracks, tin whiskers, and foreign particle contamination with exceptional clarity. Coupled with energy-dispersive X-ray spectroscopy (EDS), the SEM also performs elemental analysis on microscopic regions. This combination lets engineers identify the chemical signature of defects, making it straightforward to spot issues like short circuits, open circuits, corrosion, and plating anomalies. FIB Nanoscale Cutting: The "Scalpel" for Internal Structures While the SEM excels at surface imaging, the FIB takes over when you need to see what is happening inside the board. Using a nanometer-precision ion beam, the FIB performs targeted cross-sectioning at the exact defect location. It prepares ultra-thin slices through multi-layer boards, blind vias, and buried vias, exposing internal structures that mechanical sectioning simply cannot reach. Think of the FIB as a microscopic surgical tool. It removes material with nanometer accuracy, leaving a clean cross-section ready for imaging and analysis.   CIQTEK Semiconductor Showcase: See It in Action   The Beauty of the Microscopic World, Revealed in Every Detail. Here are real examples of CIQTEK electron microscopes in PCB cross-section observation: Solder Joint Interface Panorama Low magnification observation of capacitor overall morphology, viewing the real microscopic structure of the capacitor solder joint interface from the inside IMC Layer Evaluation Evaluating interlayer bonding, measuring IMC thickness and uniformity, detecting voids, cracks, and interface defects Multi-Layer Board Inner Structure Clear observation of IMC layer morphology, thickness, continuity, and density at the solder pad and solder interface Process Reliability Evaluation Evaluating trace pattern, thickness, etching quality and copper-to-substrate bonding, detecting line shift, etch defects, delamination, voids, and analyzing plating layer quality for PCB process control and reliability assessment   Built for Labs That Demand Reliability   CIQTEK develops its electron microscopy platforms from the ground up, covering core algorithms through hardware design. This vertical integration ensures consistent performance and long-term supply stability, which matters for labs running continuous production or multi-year research programs. The company backs its instruments with responsive technical support and regular software updates, helping users keep their systems running efficiently over time.   Get in Touch If you are evaluating SEM or FIB systems for ...

Temperature is not just an environmental setting in electron paramagnetic resonance (EPR) spectroscopy. It is a core experimental parameter, right up there with microwave power and magnetic field range. Choose the right temperature, and you unlock sharper signals, stronger sensitivity, and structural details that room-temperature measurements simply cannot reveal. Choose wrong, and your signal may disappear entirely. This guide walks through the physics of variable-temperature EPR and helps you pick the right setup for your samples. Why Temperature Matters So Much in EPR Every EPR experiment involves three questions. How does temperature reshape the microscopic spin environment? How does it affect spectral interpretation? And which systems absolutely require variable-temperature measurements? Let us break it down. Cooling: The Simplest Way to Boost Sensitivity The EPR signal comes from a simple fact. Unpaired electrons occupy two spin energy levels, and the difference in population between those levels is what we detect. In an external magnetic field B0, electron spins undergo Zeeman splitting, creating two levels with ms = +1/2 and ms = -1/2. The energy gap between them is: The Boltzmann distribution governs how electrons populate these levels. The population ratio depends on temperature in a very direct way: Here is what this means in practice. The EPR signal intensity is proportional to the population difference between the two levels. That difference scales as 1/T. In other words, lower the temperature, and your signal gets stronger. Period. Temperature is an independent, fully controllable variable, so cooling your sample is the most fundamental and direct way to boost absolute sensitivity in EPR spectroscopy.   EPR spectra of a weak coal sample measured at different temperatures. Lower temperatures deliver dramatically stronger signals. (Measured on CIQTEK EPR system.) Cooling Slows Relaxation, Revealing Hidden Signals Temperature does not just affect signal strength. It also controls spin relaxation, which determines whether you can detect a signal at all. Relaxation in magnetic resonance falls into two categories. Spin-lattice relaxation (T1). This is the process where excited spins exchange energy with the surrounding crystal lattice. It is highly temperature-sensitive. At room temperature, lattice vibrations are vigorous. Excited spins dissipate their energy quickly, so T1 is short. Cool the system down, and you effectively "freeze" those lattice vibrations. T1 lengthens dramatically. Spin-spin relaxation (T2). This arises mainly from magnetic dipolar interactions between neighboring spins. It is less directly affected by temperature.   Spin-lattice relaxation rate as a function of temperature. The strong temperature dependence shows why cooling is essential for short-relaxation systems. (Ref: Phys. Chem. Chem. Phys., 2020, 22, 15751-15758) T2 controls the spectral linewidth. The homogeneous linewidth is inversely proportional...

CIQTEK CAN400 NMR Spectrometer Becomes a Trusted Research Partner at China Pharmaceutical University Some NMR labs are busy. And then there are labs like the one at China Pharmaceutical University, where the instruments run around the clock, bookings stretch past midnight, and the sample queue fills every available slot. In that kind of environment, the instrument at the center of it all has to deliver. Clean spectra, day after day. No downtime. And it has to be simple enough for graduate students to run on their own during those late-night shifts. At China Pharmaceutical University (CPU), the CIQTEK CAN400 NMR spectrometer has met all of these demands. After nearly a year of continuous, high-volume operation, it has become a workhorse in the university's testing platform. It handles over 100 samples per day. It has maintained a zero-failure record. And perhaps most importantly, the researchers who rely on it say the data looks great. In this article, we will walk through how CPU selected the CAN400, how it has held up in one of the busiest academic NMR labs around, and why the day-to-day details matter just as much as the numbers on a spec sheet. Why NMR Spectroscopy Sits at the Heart of Pharmaceutical Research To understand why CPU needed a dependable NMR system, it helps to know what kind of institution this is. China Pharmaceutical University sits at the foot of Zhongshan Mountain, along the Yangtze River in Nanjing. It was founded over eighty years ago, and it has built a reputation as one of the top schools for pharmaceutical research and education in China. The university's pharmacy program earned an A+ rating in China's most recent national discipline evaluation. Its medicinal chemistry program has been ranked first in China and third globally, with a long history of producing influential research in drug design, molecular synthesis, and bioactive compound modification. At the heart of all this is organic chemistry. Every new drug candidate starts as a molecule that someone has to design, synthesize, and then characterize. That is where NMR spectroscopy comes in. For medicinal chemists, NMR is not a nice-to-have tool. It is the primary method for confirming molecular structures, assessing purity, and collecting the analytical data that supports publications and patent filings. So it is no surprise that the NMR lab at CPU is one of the busiest places on campus. The spectrometers run twenty-four hours a day. Students and faculty carry NMR tubes in and out of the lab at all hours. For countless research projects, the NMR spectrum is the first real data point that tells a researcher whether their synthesis worked. It is the bridge between an idea and a verified result. Given this workload, the university needed an instrument that could keep up. Solid technical performance. Continuous operation without issues. And it had to be easy enough for anyone to use, from first-year grad students to senior faculty.  The College of Science building ...