一般財団法人材料科学技術振興財団　MST List of Products and Services

MST offers a range of technologies suitable for evaluating the internal structures of electronic devices, and we propose analytical methods tailored to the observation field and objectives. This document presents case studies investigating specific areas of devices using X-ray CT and FIB-SEM. First, we observed the internal structure of the entire sample using X-ray CT to explore specific areas. Next, we used FIB-SEM to examine the detailed structures of the specific features identified on the vias.

Cream solder (solder paste) is a paste-like solder made by mixing metal powder with flux, such as rosin, and is used when mounting electronic components on a substrate. The solder flux contains various organic components ranging from low molecular to medium and high molecular weight, including solvents, activators, rosin, and thixotropic agents. Here, we present examples of a wide-ranging qualitative analysis of these components using GC/MS and LC/MS.

Two-component epoxy resin cures by mixing the base agent and the hardener. Unlike one-component systems, it has the advantage of curing without the need for heating, making it widely used as adhesives, paints, and resins. In its qualitative analysis, the cured resin, which is insoluble in solvents, can primarily be evaluated for the base agent using thermal decomposition GC/MS. On the other hand, for the evaluation of the hardener, it may be necessary to measure it in its pre-cured state depending on the type. This document presents a case where a polymercaptan hardener was measured in its pre-cured solution state, and structural estimation was conducted using a combination of ionization methods (EI and FI methods).

From the analysis of the Cu2p3/2 spectrum and Cu Auger spectrum, it is possible to evaluate the bonding state, quantitative assessment, and film thickness of the Cu surface. Major application examples include the evaluation of CMP processing and cleaning of Cu wiring, as well as the investigation of rust and discoloration of Cu electrodes. We will summarize the surface states of Cu treated with various processes and the thickness of the oxide film. (Measurements can be conducted immediately after treatment in a clean room environment.)

In HAXPES, it is possible to obtain information from deep positions (up to about 50 nm) from the sample surface. Furthermore, by using a two-dimensional detector for angle-resolved measurements, data obtained at a wide range of photoelectron emission angles can be divided into information corresponding to different angles, that is, varying detection depths. This allows for a comparison of depth-resolved bonding states to greater depths than XPS in a non-destructive manner. It is effective for evaluating materials where state changes extend not only to the surface but also into the bulk.

Optical fibers have a structure that consists of a core with a high refractive index surrounded by a cladding layer with a low refractive index. Due to the difference in refractive indices, light is totally internally reflected at the boundary and transmitted. Therefore, it is important to analyze the selection of materials, the presence of impurities, adhesion, coating conditions, and contaminants. Optical fibers can be broadly classified into two types: plastic and quartz. This document presents a case study in which the materials of the core and cladding were identified by analyzing the cross-section of plastic optical fibers using TOF-SIMS. Measurement method: TOF-SIMS Product field: Optical fibers, electronic components Analysis purpose: Qualitative evaluation, organic matter evaluation, composition distribution evaluation "For more details, please download the document or contact us."

To investigate the causes of defects such as poor adhesion, it is important to gain insights into the surfaces of wafers and devices. In this instance, hydrophobic areas were observed on a silicon wafer, prompting wide-area imaging using TOF-SIMS. As a result, components estimated to be silicone oil, CF-based grease, and paraffin oil were identified from the hydrophobic areas. TOF-SIMS typically has a measurement field of view up to 500μm square, but by moving the stage during measurement, it is possible to evaluate wide-area distributions. Measurement method: TOF-SIMS Product fields: Devices, Displays, Electronic Components, Manufacturing Equipment Analysis objectives: Qualitative, Imaging, Composition Distribution Evaluation For more details, please download the materials or contact us.

We provide suitable analysis menus for essential components of EVs, including onboard batteries and devices.

TOF-SIMS (Time-of-Flight Secondary Ion Mass Spectrometry) is a method that can sensitively evaluate organic and inorganic substances on the very surface, and it can be used as an analytical tool for various quality control processes of products. For example, it can be used for regular checks of surface contaminants during product storage, investigating the causes when defects such as peeling or discoloration occur in products, and analyzing changes in key components before and after altering manufacturing conditions. This document presents an example of comparing the surfaces of silicon wafers stored under different environments, focusing on the representative contaminant polydimethylsiloxane (PDMS). Measurement method: TOF-SIMS Product fields: Electronic components, manufacturing equipment, parts, and others (general electronics) Analysis purposes: Surface analysis, evaluation of chemical bonding states, failure analysis, defect analysis, and others (contamination assessment, quality control) For more details, please download the document or contact us.

Multilayer Ceramic Capacitors (MLCC) are capacitors that have a laminated structure consisting of internal electrodes (metal) / dielectric layers (insulator) / internal electrodes (metal). One of the issues with MLCCs is the insulation degradation (lower resistance) of the dielectric layer under high electric fields and high temperatures, which can lead to short circuits between the electrodes. Visualizing the low-resistance conductive paths formed within the dielectric layer is an important clue to understanding the insulation degradation phenomenon. This document presents a case where the insulation degradation of dielectric materials due to temperature changes was visualized by combining SSRM measurement (high electric field) and heating mechanisms (high temperature). Measurement method: SSRM (Scanning Spreading Resistance Microscopy) Product fields: Dielectric materials, capacitors, MLCC Analysis objectives: Resistance value distribution, current distribution, insulation degradation evaluation For more details, please download the document or contact us.

This explains the measurement of total light transmittance and total light reflectance.

Carrier lifetime refers to the time it takes for minority carriers among the excess carriers generated during the operation of electronic devices to decay to 1/e. Proper control of this is important for managing the electrical characteristics of the device. On the other hand, luminescence lifetime indicates the time until the luminescence intensity from the sample reaches 1/e, and it can be calculated from the luminescence decay curve. Since some minority carriers emit light during recombination, it is possible to indirectly evaluate the carrier lifetime from luminescence lifetime measurements. This document presents a case study on the evaluation of carrier lifetime for 4H-SiC epitaxial substrates. Measurement method: Fluorescence lifetime measurement Product fields: Power devices, LSI/memory, electronic components Analysis purposes: Failure analysis, defect analysis, product investigation, carrier lifetime, process evaluation For more details, please download the document or contact us.

In electronic devices that use a lot of semiconductors, each component is mounted by soldering. If defects occur in the solder joints, it can lead to malfunctions in the electronic devices. Therefore, evaluating the wettability of solder is important for assessing the reliability of components. In this study, we artificially degraded the samples to examine how the wettability of the solder changes. After the constant temperature and humidity test, it was found that the wettability of the electrode surface changed. Measurement methods: Constant temperature and humidity test, solder wettability test Product fields: Power devices, LSI/memory, electronic components Analysis purpose: Degradation investigation, reliability evaluation For more details, please download the materials or contact us.

Lithium hexafluorophosphate (LiPF6), the main component of the electrolyte in lithium-ion batteries, is known to undergo hydrolysis upon reaction with moisture, generating fluoride ions. This document presents a case where the concentration of fluoride ions produced by the atmospheric exposure of the electrolyte (1M LiPF6, EC:EMC = 3:7 v/v) was evaluated using 19F-NMR, which allows for absolute quantification without the use of standard compounds. Measurement method: NMR Product field: Secondary batteries and electronic components Analysis purpose: Failure analysis, defect analysis, degradation investigation For more details, please download the document or contact us.

Gallium nitride (GaN), a wide bandgap semiconductor, is used in a wide range of fields such as power devices and communication/optical devices. When fabricating devices, the shape and roughness of the wafer surface significantly impact device performance. During the growth of GaN wafers, a step-terrace structure is formed on the surface due to stress effects from lattice mismatch with the supporting substrate. This document introduces a case where the step-terrace structure of the GaN substrate surface was visualized using AFM, and the terrace width, step height, surface roughness, and off-angle were evaluated. Measurement method: AFM Product fields: Power devices, electronic components, lighting Analysis purpose: Shape evaluation, structural evaluation For more details, please download the document or contact us.

Environmental Testing Evaluates the resistance of electronic components and devices when subjected to environmental stress. Reliability Evaluation Testing Assesses items related to the reliability and safety of the product.

In HAXPES, hard X-rays (Ga radiation) are used for excitation, which results in different positions of the Auger peaks compared to the Al and Mg radiation typically used in standard XPS measurements. Therefore, even in samples where the photoelectron peaks and Auger peaks overlap in Al and Mg measurements, this overlap can be avoided in Ga measurements, allowing for a detailed evaluation of the bonding states. This document presents the spectra of Kovar (an alloy of Fe, Ni, and Co) and GaN measured using Ga radiation (equipped with HAXPES) and Al and Mg radiation (equipped with XPS).

Polyimide has very high heat resistance and excellent electrical insulation and mechanical properties, making it an essential material not only for electronic components but also for a wide range of fields such as precision machinery, automobiles, and aerospace. In its reliability evaluation, research on imide bonds is important. This document presents an example of XPS measurements conducted on polyimide before and after heating. Changes in the amount of oxygen and the chemical shifts of carbon, nitrogen, and oxygen confirmed that imidization progressed after heating. Additionally, by performing waveform analysis, it is also possible to determine the proportion of polyimide present.

UV-curable resins harden quickly when exposed to ultraviolet light and are widely used as coating materials and adhesives due to their ease of use. In acrylate resins, which are commonly used materials, the molecular ions of acrylate monomers are difficult to detect using the conventional ionization method of EI in GC/MS analysis, leading to insufficient structural estimation. Here, we introduce a case where, in addition to the partial structural information obtained from the conventional EI method, the use of the soft ionization method FI enabled the detection of molecular ions, allowing for the estimation of the structure of acrylate monomers.

Resins (synthetic polymers) are polymers of monomers and have characteristic functional groups depending on their type. Due to their structure, they exhibit properties such as heat resistance, toughness, and electrical insulation, making them widely used in packaging materials, adhesives, paints, and more. Structural analysis is important for understanding the properties of resins, and common analytical methods include FT-IR and thermogravimetric GC/MS. FT-IR allows for the evaluation of functional groups, while thermogravimetric GC/MS enables the assessment of monomers and partial structures, so by combining these two methods, structural analysis of a wide variety of resins becomes possible.

Resins that excel in chemical resistance and electrical insulation are used as insulators, coatings, and adhesives for various electronic components. FT-IR (Fourier Transform Infrared Spectroscopy) can investigate the causes of defects such as the degree of curing of resins, making it effective for product development. As an example, we will introduce a case where the degree of curing of UV-curable resins was evaluated. It is effective for examining the UV exposure time in adhesives and assessing the curing state when delamination occurs in products.

This document presents an example of evaluating organic contamination through bonding state mapping using XPS. This bonding state mapping is obtained by acquiring XPS spectra of the element of interest at several hundred points within the plane and plotting the distribution of peak intensities corresponding to the energy positions of specific bonding states. Depending on the size of the area of interest, evaluation areas can be set to arbitrary sizes ranging from approximately 1mm to 20mm square, making it particularly suitable for assessing contamination, discoloration, and surface treatments on the order of millimeters. Similar evaluations can also be conducted for metals and silicon, in addition to carbon.

This is an example of wide-area quantitative mapping using XPS. We evaluated organic residue on silicon wafers using the following procedure. To graph the amount (atomic concentration) rather than peak intensity, it is less affected by sample roughness and allows for data acquisition over a wide area. It is suitable for investigating organic and inorganic contamination, discoloration, surface treatments, etc., as it enables an overview assessment of the compositional distribution on the sample surface.

Tin (Sn), such as in solder, is used in many electronic components. In the XPS analysis of the Sn surface, by using the 4d orbitals in addition to the quantitative and state analysis typically performed with the 3d orbitals, it is possible to separate the oxidation states (divalent Sn2+ (SnO) and tetravalent Sn4+ (SnO2)) and calculate their ratios. Furthermore, by examining the valence band, it is possible to sensitively detect even a very small amount of the low oxidation state (divalent Sn2+ (SnO)). This document presents examples of evaluating Sn on the surface of solder using various orbitals.

Multilayer ceramic capacitors (MLCCs) are capacitors designed to increase capacitance by layering ceramic dielectric and electrodes. The electrical properties of MLCCs are significantly affected by impurities, making the evaluation of impurities in the ceramic layers and the diffusion of electrode components important. With the miniaturization of MLCCs, the ceramic layers have become thinner, making it difficult to evaluate impurities. This document introduces the results of evaluating impurities in the ceramic layers by innovating the pretreatment process.

TOF-SIMS has features such as simultaneous evaluation of organic and inorganic materials, capability for micro-area analysis, and high sensitivity for analyzing the very surface, making it effective for residue investigation in cleaning processes. An example is presented where pure water was dried on a silicon wafer. Optical microscopy only reveals slight point-like foreign substances and cloudiness. However, the results measured by TOF-SIMS showed that in the contaminated areas, organic components such as hydrocarbons, PDMS, and amides, which tend to adsorb naturally, were aggregated.

Impurities from components of the film formation device, target materials, and plating solutions can contaminate the device and have adverse effects, making the qualitative assessment of impurities on surfaces, within films, and at interfaces important. TOF-SIMS can sensitively evaluate unknown elements present on surfaces, within films, and at interfaces in a single measurement due to the following three characteristics: 1. For metallic elements, ions from m/z 1 to 800 can be detected simultaneously in one measurement. 2. Detection sensitivity of a few ppm can be achieved (varies depending on materials and ions). 3. The use of a sputter gun allows for the evaluation of depth distribution.