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

In the field of semiconductors and their manufacturing processes, it is considered important to control inorganic and organic substances present in the environment. At MST, it is possible to collect components from the indoor atmosphere using the impinger collection method and analyze the types and quantities of corrosive components in the atmosphere. This time, we will introduce a case analyzed using the impinger collection-ion chromatography method.

One method to obtain the temperature profile of gases generated during sample heating is the EGA-MS method. However, this method introduces the generated gases into the mass spectrometer as a mixture without passing through a GC column, making it difficult to identify the compounds. In such cases, by trapping the gases once and performing GC/MS measurements using the heart-cut EGA method, it becomes possible to separate and identify the compounds. This example presents a case where polyvinyl acetate was measured using the heart-cut EGA method, revealing differences in the decomposition mechanisms depending on the heating temperature.

Silicon oxide films are widely used as gate dielectrics in MOS devices and as anode materials in lithium-ion secondary batteries, but it is known that the presence of intermediate oxides and the bonding states at the interface have a significant impact on device characteristics. XAFS measurements using synchrotron radiation can detect information from a depth of several tens of nanometers from the sample surface, allowing for non-destructive analysis of the structure and bonding states in both bulk and at the interface. This document presents a case study investigating the presence of intermediate oxides in silicon oxide films using XAFS.

The concentration distribution of boron (B) in silicon (Si), which significantly affects the characteristics of device design, can be evaluated with high sensitivity and high depth resolution through SIMS analysis. However, it has been found that under general analysis conditions, distortions occur in the concentration distribution of B due to measurement-related factors. In MST, it has been confirmed that sample cooling is effective for correcting these distortions, enabling a more accurate evaluation of the concentration distribution.

Substances composed of carbon include those with crystalline structures such as diamond, graphite, carbon nanotubes, and graphene, as well as those with amorphous structures like diamond-like carbon (DLC). Raman spectroscopy is effective for the structural identification, crystallinity, and sp3 character evaluation of these materials.

In recent years, with the introduction of lead-free solder, the flux components have also been improved (with higher activity and heat resistance, etc.), leading to increased corrosiveness and a growing importance of residue issues. Therefore, the removal of flux is required. An analysis of foreign substances in the electrode parts of printed circuit boards using TOF-SIMS revealed the presence of flux components.

Raman spectroscopy is an effective method for the qualitative analysis of microscopic foreign substances. When it becomes difficult to evaluate due to the detection of background information along with the foreign substances, measurements can be performed by combining sampling. Foreign substances on electrodes with minimal background influence were identified as flux, but no information from the foreign substances could be obtained from the foreign substances on printed circuit boards (Figure 1). By performing sampling on inorganic crystals without background influence, information about the foreign substances was obtained, and the foreign substances were identified as flux (Figure 2).

We will introduce a case study of foreign substance evaluation using micro FT-IR analysis combined with sampling. Foreign substances on electrodes with almost no substrate influence were identified as flux, but no information from the foreign substances on the printed circuit board could be obtained (Figure 1). By performing sampling on inorganic crystals, information about the foreign substances was obtained, and they were identified as flux (Figure 2).

As electronic devices are increasingly used in various everyday locations, ensuring the reliability of products has become important. Since it is possible for the copper used in the wiring of printed circuit boards to migrate and cause defects in high temperature and high humidity environments, it is crucial to evaluate the components that promote migration. This case study introduces an example of quantitative analysis of cation components eluted from printed circuit boards using ion chromatography (IC). Thus, IC is an effective method for evaluating the corrosion components on the surface of solid samples.

It was found that there are water-repellent stains on the surface of the aluminum material. The stained area was adhered to tape (transferred), and analysis was conducted using TOFSIMS. Fragments identical to those from the stained area on the aluminum surface were detected from the "tape surface where the stained area was transferred," suggesting that the substance causing the stain has been transferred to the tape. This method of transferring and collecting the causative substance onto tape is effective for parts that cannot be cut.

A scanning white light interferometer (optical interferometer) can perform high-precision, non-contact three-dimensional measurements of the surface shape of a sample with "high vertical (Z) resolution (0.1 nm) and a wide (X-Y) measurement field of view (50 μm to 4.2 mm)." It is capable of measuring up to a field of view of 4.2 mm × 4.2 mm.

Organic contamination during the manufacturing process significantly affects product performance. In the analysis of organic substances in liquid samples, such as rinse solutions in the cleaning process, evaluations can be conducted using Total Organic Carbon (TOC) analyzers and Liquid Chromatography-Tandem Mass Spectrometry (LC/MS/MS). Here, we present an example of evaluation using TOC and LC/MS/MS for NPnEO (Nonylphenol Ethoxylate), one of the industrial surfactants.

A scanning white light interferometer (optical interferometer) can perform high-precision non-contact three-dimensional measurements of the surface shape of a sample with "high vertical (Z) resolution (0.1 nm) and a wide (X-Y) measurement field of view (50 μm to 4.2 mm)." An example of observing the surface shape of a Si/SiGe layered sample (crosshatch pattern) is presented. Shape evaluation with an average roughness (Ra) of approximately 1 nm is possible.

By irradiating the surface of polymer materials with ions, changes in surface properties occur. Utilizing these changes, research is being conducted in a wide range of fields, including the development of functional materials. Evaluating the changes that occur in the surface state after ion irradiation is important for efficient research and development. In TOF-SIMS analysis, using a GCIB (Gas Cluster Ion Beam) for the sputtering ion beam makes it possible to evaluate the composition and thickness of the damage layer caused by ion irradiation on the surface of polymer materials.

It is possible to directly extract small pieces from the sample (micro-sampling) and perform FIB processing.

To investigate the causes of solder delamination, it is effective to conduct component analysis of the solder and the substrate interface. TOF-SIMS is a suitable method for evaluating delaminated areas because it can simultaneously analyze elemental composition and molecular information of organic and inorganic substances, as well as perform imaging analysis. This document presents a case study analyzing the cross-section of a delaminated solder area, confirming the distribution of substrate components, resin components, and organic components other than resin.

TOF-SIMS allows for simultaneous elemental analysis and molecular information analysis of organic and inorganic substances through mass spectra obtained by locally analyzing specific areas, making it effective for evaluating foreign substances and micro-regions. This document summarizes examples of analysis in sub-micron order micro-regions. Samples that were sputter-processed with FIB on layered structures were measured using TOF-SIMS. Evaluation of sub-micron order micro-regions has been achieved.

One method for qualitative analysis of gases generated during sample heating is the pyrolysis GC/MS method, but the EGA*-MS method is effective for investigating the temperature at which each component detected here is generated. This method involves directly introducing the gases generated from the sample during temperature ramping into the mass spectrometer without passing through the GC column. This case presents an example of measuring the temperature profile of gases generated during the heating of polyvinyl acetate. * EGA: Evolved Gas Analysis

SEM-EDX analysis and AES analysis are suitable for simple investigations of discoloration and foreign substances on metal surfaces. However, when the discoloration or foreign substances are thin or small, AES analysis, which provides information from very shallow areas of the surface (about 4-5 nm), is effective. The AES equipment owned by MST can acquire SEM images, allowing AES analysis to be conducted while confirming the areas of interest using SEM images. In this case study, we will present data comparing the evaluation of discoloration on the Cu surface using AES analysis and SEM-EDX analysis. Additionally, we will also present the results of AES depth direction analysis.

SRA can analyze the depth profile of carrier concentration distribution over a wide range from shallow regions (a few hundred nm) to deep regions (a few hundred μm). It is also possible to evaluate the in-plane distribution of resistance values at the sample surface or at specified depths. As an example, we will introduce a case where the depth profile of carrier concentration distribution for a commercially available Si-IGBT chip was evaluated, including the entire chip, the field stop layer, and the lifetime killer, as well as the in-plane distribution of resistance values at the irradiation depth of the lifetime killer using SRA.

With the miniaturization of circuits, the design and development of micro vias for interlayer connections require an understanding of the quality of filling. TOF-SIMS is an effective method for evaluating the results, as it can simultaneously perform elemental analysis and analyze molecular information of organic and inorganic substances, as well as enable image analysis. This document presents a case study analyzing a sample with Cu filled in vias of approximately 0.5μm in diameter on a Si substrate. The analysis of positive ion results confirmed the distribution of Cu and Si. Measurement method: TOF-SIMS Product fields: LSI, memory, electronic components Analysis objectives: Composition distribution evaluation, failure analysis, defect analysis For more details, please download the document or contact us.

XPS and AES are surface-sensitive analytical techniques widely used for evaluating sample surfaces, but by combining them with ion etching, depth profiling analysis becomes possible. When conducting depth profiling analysis, it is important to appropriately differentiate between XPS and AES according to the area to be measured and the material of the sample in order to perform analysis that aligns with the objectives. The characteristics of depth profiling analysis using XPS and AES will be compared using the analysis of SUS passive films as an example.

We will introduce a case where the permeability of water (H2O) in glass materials was evaluated by measuring the distribution of deuterium (D). When hydrogen (H) is already present, it is difficult to distinguish whether the hydrogen is due to the influence of water. Therefore, treatment with heavy water (D2O) was performed, and the distribution of the stable isotope deuterium was measured in depth using SIMS. By examining the depth distribution of deuterium, it is possible to estimate how deep the water has penetrated.

In a STEM device equipped with a spherical aberration correction function (Cs corrector), high-resolution observation and high-sensitivity analysis at the atomic level are possible. The resolution is approximately 0.10 nm.

When materials undergo chemical reactions and phase changes with increasing temperature, performing XRD measurements while heating is effective. We present a case where high-temperature XRD measurements were used to identify the decomposition products of copper(II) sulfate pentahydrate. The results showed that the diffraction peaks changed at the temperature where decomposition occurred, clearly confirming the changes in the crystal structure. In MST, it is possible to conduct Out-of-plane XRD measurements and In-plane XRD measurements while heating.

AES analysis is a method for obtaining compositional information from the surface down to a depth of several nanometers, and it is an effective analysis for investigating the composition of contaminants and foreign substances that occur on the surface during the manufacturing process. Since it rarely detects information about the substrate or base material, it allows for a simple examination of only the abnormal areas, such as foreign substances, without preprocessing. Additionally, by conducting surface analysis, it is possible to obtain elemental distribution images. In this case study, we will present data evaluated using AES analysis regarding foreign substances present on a Si wafer.

AES analysis is a method for obtaining compositional information from the surface to a depth of several nanometers. By performing AES measurements on the cross-section of a sample to obtain elemental distribution images, it is possible to clearly evaluate the layered structure. In addition to evaluating layered structures and conducting elemental analysis of the inner walls of trenches and holes, combining mechanical processing and ion beam processing allows for the assessment of thin alloy layers and phenomena such as diffusion and segregation of elements. In this case, we will present data evaluated using AES analysis for a thin film deposited on a silicon substrate.

In general, to remove dirt, a cotton swab may be dipped in ethanol and used for wiping. When the surface of a Si wafer was wiped with a cotton swab dipped in ethanol, an analysis was conducted using TOF-SIMS to determine what was distributed on the surface. The Si wafer wiped with the cotton swab showed stains that were not visible under an optical microscope, and it was found that these were due to the cotton swab. TOF-SIMS is effective for analyzing stains that are not visible under an optical microscope and for cleaning residues.

TDS is a method that heats samples in high vacuum (1E-7 Pa) and detects the gases that are released. By heating the sample at a constant rate in high vacuum, it is possible to confirm the temperature dependence of even trace amounts of desorption (at the monolayer level). Additionally, for some components, it is also possible to calculate the number of molecules of the desorbed gas. We will introduce examples of TDS applied to representative materials.

Carbon materials, widely used in industrial components and medical devices, have different properties depending on their structure and crystallinity, making it important to evaluate their state. This document presents evaluation examples using high-sensitivity and high-spatial-resolution Raman spectroscopy. The distribution of the crystalline state of graphite, a carbon material, was visualized through mapping. It allows for a visual capture of the quantity of defects, whether high or low.

When ions or electron beams are irradiated onto Si, a portion of the "substitutional carbon" that is slightly contained in Si changes into "interstitial carbon." This interstitial carbon is believed to influence the electrical properties of the device. The behavior related to interstitial carbon can be observed very sensitively through low-temperature PL analysis, allowing insights into trace amounts of carbon below the detection limit of SIMS analysis. This document presents examples of low-temperature PL analysis and SIMS analysis conducted on Si substrates subjected to ion implantation.

AES analysis is a method for obtaining compositional information and elemental distribution at the very surface (to a depth of a few nanometers). By combining it with cross-sectional processing, similar information can also be obtained within layered structures and at structural interfaces. This allows for the evaluation of alloy layers, elemental diffusion, and segregation, making it effective for failure analysis and defect investigation of devices. Below, we present a case where a cross-section was prepared using IP processing to evaluate the state near the bonding interface of wire bonding, followed by assessment through AES analysis.

Corrosive gases such as etching gases have a significant impact on the degradation of semiconductors, electronic components, and devices. Below, we present an example of capturing corrosive gases using TDS (Temperature-Programmed Desorption Gas Analysis). It was confirmed that HCl, a corrosive gas, desorbs with the increase in temperature of the sample. Since TDS can capture desorption in the m/z range of 2 to 199 while heating, it is effective for investigating the types and amounts of corrosive gases as well as their temperature dependence of desorption.

Positive-type photoresists are widely used as photolithography materials in semiconductor device manufacturing. The materials used in the resist vary significantly depending on the exposure light source, but for g-line and i-line resists, phenolic novolak resin is generally used as the base resin, and naphthoquinone diazide compounds are used as the photosensitizer. This case study introduces an example where naphthoquinone diazide compounds were decomposed using thermal decomposition GC/MS method to estimate the structure of the parent nucleus.

IGBT (Insulated Gate Bipolar Transistor) is used in various products as a power semiconductor module, ranging from home appliances to industrial equipment. Lifetime control is implemented for performance improvement in IGBTs, but this control is achieved by creating defects (lifetime killers) in the drift layer. By conducting low-temperature micro-PL analysis from the cross-section, it is possible to gain insights into lifetime killers.

Polymers are known to exhibit diverse functions by altering their composition and structure, and they are utilized in various products. In the evaluation of polymers, assessment in real environments is crucial. This time, we will introduce a case where the shape of polymers on a substrate was visualized in the atmosphere and in aqueous solution using an environmental control atomic force microscope (AFM). Additionally, by combining data analysis, we quantified the dispersion of polymer particles.

The gas generation concentration device is an apparatus that traps gases generated from samples placed inside a chamber into a collection tube. By trapping in the collection tube, trace amounts of desorbed components can be concentrated and measured with high sensitivity using GC/MS. Depending on the type of sample, a suitable size of chamber can be selected, and it can accommodate heating up to 350°C. - Compatible with relatively large samples (on the order of several centimeters) - Allows for measurements with 2 to 3 orders of magnitude higher sensitivity compared to the headspace method - Enables evaluation of organic contamination from both sides of a wafer - Allows for evaluation of organic contamination on photomasks (reticles) - Quantitative analysis using hexadecane, decamethylcyclopentasiloxane, etc., is possible.

In AES analysis, the SEM observation function is included, allowing for the measurement of specific areas on the sample surface. Additionally, since measurements can be taken in sub-micrometer micro-regions, it is possible to target specific areas for measurement not only on flat samples like substrates but also on samples with spherical or curved shapes, which are less affected by curvature. Below is an example of evaluating the oxide film thickness on solder ball surfaces with different surface shapes.

Graphene, a monolayer form of graphite, is expected to be applied in a wide range of fields such as batteries, transparent electrodes, and sensors due to its excellent properties, including toughness, high electrical conductivity, and high thermal stability. It is also said that the types and amounts of functional groups present on the surface vary depending on the manufacturing method, and clarifying its structure is an important point for improving performance. This case study introduces a comparison of the functional groups of two types of graphene using thermal decomposition GC/MS method.

We will introduce a case where lenses and CMOS sensor chips were extracted from commercially available smartphones and evaluated. Depending on the purpose, we created flat and cross-sectional surfaces through polishing and FIB processing, and confirmed the layered structure and layers using TEM and SEM. Furthermore, we identified the types of films using EDX. At MST, we can handle everything from disassembly to analysis in a consistent manner.

In order to investigate the causes of device failures that cannot be identified through visual inspection, non-destructive evaluation methods such as X-ray CT may be necessary. Using X-ray CT, we measured the faulty transistor and checked its internal condition. As a result, we confirmed a wire breakage, and it was also found that the mold resin surrounding the broken wire had deteriorated due to heat and other effects at the time of the breakage.

Resins that excel in chemical resistance and electrical insulation are used as insulators, coatings, and adhesives for various electronic components. FT-IR analysis 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 epoxy resin was evaluated.

TDS (Thermal Desorption Gas Analysis) is a method that allows for the confirmation of desorbed components and desorption temperatures while heating a sample in a vacuum (1E-7 Pa). Furthermore, by combining the results of TDS with GC/MS (Gas Chromatography-Mass Spectrometry), which can identify organic substances, it is possible to evaluate the desorption temperatures of specific desorbed components in a vacuum. Below, we present an example of a combined analysis of TDS and GC/MS conducted on graphene.

Soldering of metals is one of the essential processes in the field of electronics. It is known that the outgassing that occurs when metal and solder are heated in contact can lead to voids. Below, we introduce a case where TDS analysis (Thermal Desorption Spectroscopy) was performed with solder placed on a copper plate. TDS can evaluate the outgassing associated with the heating of materials. By bringing the copper plate and solder into contact and heating them simultaneously within the TDS apparatus, we were able to capture outgassing in an environment close to the actual process.

Resins that excel in chemical resistance and electrical insulation are used as insulators, coatings, and adhesives for various electronic components. FT-IR analysis can investigate the causes of defects such as the degree of curing of the resin, making it effective for product development. As an example, we will introduce a case where the imidization rate was evaluated from the imide groups of polyimide. It is effective for process verification by comparing the imidization rate in the insulating film on the device with data on water resistance, heat resistance, and so on. Evaluation is possible in both chip and wafer states.