Material & Processes
The Materials and Processes Lab includes resources for components, PCBs, assembled PCBs, crimps, welds & materials testing, analysis and measurements. We have expert knowledge of the IPC, MIL, IEC, ECSS, JEDEC, among others, standards and conduct the test according to such test methods.
For sample preparation, this lab is equipped for cutting, grinding, polishing and sampling of a wide variety of material types and sizes.
The laboratory also offers advanced characterisation testing in order to assess the mechanical, physical and chemical properties of materials, connecting in many cases microscopic characteristics to macroscopic properties.
The M&P lab has a proven heritage and recognised expertise in assessing the reliability of the PCB manufacturing and soldering for space applications. PCB assembly and soldering operations remain amongst the more delicate space-components fabrication tasks as they may compromise the integrity and performance of the whole system. For this reason, ESA pays special attention to the workmanship assessment and have issued specific regulations to cover these topics, ECSS-Q-ST-70-61C. These tasks require specifically trained and skilled analysts holding the applicable ESA certifications.
Main services
Cross section Analysis
The cross-sectioning process provides access to the device’s internal structure, its materials, and design. Such components as diodes and capacitors, and silicon dice are often subjected to cross-sectioning to detect the defects which could not be found using other testing techniques.
Cross-sectioning generally involves three discrete steps: mounting the sample in a block of epoxy resin to form the specimen, grinding or cutting the specimen and finally polishing the surface so exposed. The main purposes of these steps are exposed to the hereafter.
Mounting:
- To hold the sample and their internal elements together during the sectioning process.
- To provide a means of holding the sample during grinding and polishing operations.
- To provide a convenient means of positioning the sample on the microscope stage for examination.
FIGURE: Cross–sectioning on a connector at ALTER TECHNOLOGY (grinding process).
The purpose of grinding is to quickly reach a broad region of interest. This enables the exact area of interest to be reached by subsequent slower polishing techniques in a reasonable period of time. Grinding is carried out by using silicon carbide paper disks mounted on horizontal rotary grinding wheels. A continuous flow of water is used for cooling and cleaning the wheels.
FIGURE: Cross-sectioned wired connector
The purpose of polishing is to eliminate surface scratches produced during grinding while maintaining sectioned sample features essentially unchanged so that a true view of these features is adequately available for visual inspection.
FIGURE: PCB cross-section with soldered ceramic capacitors
After fine polishing, the samples are examined microscopically using a compound microscope with vertical illumination to locate, identify and characterize defects which constitute reject criteria.
A key element in the performance of cross-section is the ability of the inspector to detect and identify problems and non-conformances of the products. An extensive experience in the technologies examined, knowledge about acceptance criteria and cumulated know-how are a prerequisite for a proper test execution.
Assembled PCB qualification/testing
PCB qualification includes testing and inspection according to ECSS standards, such as vibration, thermal cycling tests and cross-section evaluation.
To fulfill the requirements of standard ECSS-Q-ST-70-61C, this set of tests can only be carried out in a satisfactory audited ESA laboratory. Materials & Processes Laboratory is listed as an ESA recommended microsectioning facility and the only one accredited ISO/IEC 17025:2017 to carry out microsectioning inspection together with the environmental, vibration and shock tests for PCB and SMD verifications
Common Inspection Standards:
- IPC-A-600 – Acceptability of Printed Boards
- IPC-A-610 – Acceptability of Electronic Assemblies
- ECSS-Q-ST-70-60C – Qualification and procurement of printed circuit boards
- ECSS-Q-ST-70-61C – High Reliability Assembly for Surface Mount and Through-Hole Connections
Crimp quality services
The Materials & Processes Lab has the capability to assess the quality of crimping wires connections following the requirements defined in standard ECSS-Q-ST-70-26C for high reliability electrical connections for use on spacecraft and associated equipment operating under high vacuum, thermal cycling and launch vibration.
As part of the external inspection of such connections, the indentation depth and dimensional verifications can be measured to evaluate the agreement with the manufacturer specifications.
The tensile test is a means of evaluating the mechanical properties of the crimped connections. This test could be performed in a a non-destructive way (to the minimum tensile value fixed by the manufacturer) or as a part of a destructive test (to the breaking strength of the crimped connection).
Cross-section inspection is an essential element of crimp quality validation, and it is mandatory in several regulations including ECSS specifications required by the European Space Agency (ESA) projects. For this inspection, the connector is cross-sectioned in order to gain access to the internal structure of the crimped area. This allows us to deeply assess the real quality of the crimped area by analyzing several critical factors such as the void percentage, the barrel and wires deformation, braids distribution and the barrel and wire integrity (cracks formation and plating delamination).
Advanced Materials Analysis
The laboratory has a wide analytical measurement equipment to evaluate chemical composition, elemental analysis and contamination testing. This analysis can require the application of a combination of different techniques and expertise, including SEM-EDS, FT-IR, Raman microscopy, XPS and XRF.
- SEM-EDS: Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) allow for targeted analysis of sample surfaces. These techniques are widely used for material surface analysis, investigation of product failures, reverse engineering, contaminant identification, solder joint analysis and more.
- Raman microscopy: You can interpret Raman spectra to identify chemicals and get structural information. Raman scattering results from the interaction of light with molecular vibrations. These vibrations are very sensitive to changes in chemistry and structure, so you can spot subtle differences in molecular environment.
- FT-IR: Fourier Transform Infrared Spectroscopy, also known as FTIR Analysis or FTIR Spectroscopy, is an analytical technique used to identify organic, polymeric, and, in some cases, inorganic materials. The FTIR analysis method uses infrared light to scan test samples and observe chemical properties.
- XPS: Is routinely used to analyze inorganic compounds, metal alloys, polymers, elements, catalysts, glasses, ceramics, paints, papers, inks, woods, plant parts, make-up, teeth, bones, medical implants, bio-materials, coatings,viscous oils, glues, ion-modified materials and many others.
SEM-EDS
Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) allow for targeted analysis of sample surfaces. These techniques are widely used for material surface analysis, investigation of product failures, reverse engineering, contaminant identification, solder joint analysis and more.
Raman microscopy
You can interpret Raman spectra to identify chemicals and get structural information. Raman scattering results from the interaction of light with molecular vibrations. These vibrations are very sensitive to changes in chemistry and structure, so you can spot subtle differences in molecular environment.
FT-IR
Fourier Transform Infrared Spectroscopy, also known as FTIR Analysis or FTIR Spectroscopy, is an analytical technique used to identify organic, polymeric, and, in some cases, inorganic materials. The FTIR analysis method uses infrared light to scan test samples and observe chemical properties.
XPS
It is routinely used to analyze inorganic compounds, metal alloys, polymers, elements, catalysts, glasses, ceramics, paints, papers, inks, woods, plant parts, make-up, teeth, bones, medical implants, bio-materials, coatings,viscous oils, glues, ion-modified materials and many others.
Coating / Surface Characterization
ALTER performs a wide range of tests on coatings to characterise their properties, including:
- Tg and CTE by TMA
- Layer thickness with micro-section analysis
- Surface energy with test inks (ISO 8296)
- Adhesion test with cross-cut test: the most common tests to evaluate the coating adherence to the substrate
- Measurement of roughness
Additional services
- Coating Analysis: Assessment of the performance and adhesion of coatings applied to PCBs and components, identifying defects and enhancing durability.
- Crimping Qualification: We ensure the quality and reliability of crimped electrical connections, meeting ESA and IPC standards.
- Press-fit Connector Qualification: Validation of Press-fit connectors’ performance, crucial for secure and reliable connections in demanding environments.
- Whiskers analysis: Comprehensive evaluation of tin whiskers growth to mitigate risks of short circuits and failures in electronic assemblies.
- C-SAM (Scanning Acoustic Microscopy): Non-destructive inspection technique to detect internal defects such as delaminations, voids, and cracks in electronic packages and assemblies
- Radiographic Inspection (2D X-ray / 3D CT): In-depth analysis of solder joints, internal structures, and hidden features using advanced X-ray imaging to ensure integrity and detect manufacturing anomalies
Accredited Testing Services
Materials & Processes laboratory holds the necessary accreditations to meet the requirements of our customers and show the lab´s inspector competence, including:
ENAC ISO/IEC 17025:2020 accredited for:
- Assembled PCB testing
- Crimping qualification
- Dimensional testing
ESA Category A laboratory and recomended facility for inspection, microsectioning and assessment of the microsectioning to a verification programme in compliance with ECSS-Q-ST-70-61C.
M&P laboratory activities meet the ISO 9001 & ISO 9100 quality standards.
Our team is certified according to:
- ECSS-Q-ST-70-61C – High Reliability Assembly for Surface Mount and Through-Hole Connections
- ECSS-Q-ST-70-26C – Crimping of high-reliability electrical connections
- IPC-A-600 – Acceptability of Printed Boards
- IPC-A-610 – Acceptability of Electronic Assemblies