SEM-EDS

Gideon Analytical Laboratories received several RY4S-UAC110-120V power relays for failure analysis. A relay is an electrically operated switch. Many relays use an electromagnet to operate the switch, but other operating principles are also used, such as solid-state relays. Relays are used where it is necessary to control a circuit by a separate low-power signal, or where several circuits must be controlled by one signal. Relays are used to control a high power or high voltage circuit with a low power circuit. The low power is isolated from the high power circuit. The RY4S-UAC110-120V power relays have 4PDT contact configuration, 5A contact current, quick connect relay terminals, and silver contact material. Their coil resistance is 4.29kohm. When given the RY4S-UAC110-120V power relays, we were to tasked with determining the stuck core/contact cause.

Gideon Analytical Laboratories received a TI TMS320F28335PGFA Digital Signal Processor for failure analysis. Digital Signal Processing applications include audio and speech processing,sonar,radar, and other sensor array processing,spectral density estimation,statistical signal processing,digital image processing, among many others. The TI TMS320F28335PGFA features high-performance static CMOS technology, a 32-bit CPU, 16 x 16 and 32 x 32 MAC operations, and Harvard bus architecture. It has up to 88 individually programmable, multiplexed GPIO pins with input filtering. We were advised to pay special attention to pins 141 and 148 because they were possibly nonfunctional in operation.

Gideon Analytical Laboratories received three different vendor 100-ohm resistors, made by Vishay, RCD, and Stackpole, respectively. The two Stackpole resistors were open. A resistoris a passive two-terminal electrical component that implements electrical resistance as a circuit element. In electronic circuits, resistors are used to reduce current flow, adjust signal levels, to divide voltages, bias active elements, and terminate transmission lines, among other uses. Our goal was to test the functionality the Vishay, RCD, and Stackpole resistors, and if any were failing, determine the cause of the failure.

Gideon Analytical Laboratories received several T491D475K050AT Kemet tantalum capacitors for electronic failure analysis. A capacitor is a passive two-terminal electronic component that stores electrical energy in an electric field. While some capacitance exists between any two electrical conductors in proximity in a circuit, a capacitor is a component designed to add capacitance to a circuit. The Kemet T491D475K050AT has a capacitance of 4.7 uF, a voltage rating of 50 VDC, and a tolerance of 10%, measures 7.3mm x 4.3mm x 3.1mm (LWH), has a minimum operating temperature of -55 degrees Celsius and a maximum operating temperature of 125 degrees Celsius. One of these capacitors had already been tested and found to be a dead short. The other capacitors were to be used to determine whether acid had affected the forming voltage oxide.

Gideon Analytical Laboratories received several Murata Electronics GCM21BR70J106KE22L Multi-Layered Ceramic Capacitors (MLCCs) for failure analysis. An MLCC consists of a number of individual capacitors stacked together in parallel and contacted via the terminal surfaces. The starting material for all MLCC chips is a mixture of finely ground granules of paraelectric or ferroelectric raw materials, modified by accurately determined additives. The Murata Electronics GCM21BR70J106KE22L has a capacitance of 10 uF, a DC voltage rating of 6.3 VDC, has an XR7 dielectric, and has an SMD/SMT termination style. It has a minimum operating temperature of -55 Celsius and a maximum operating temperature of 125 Celsius. The goal was to determine why these MLCCs were failing, and while we did discover why, that is not the only thing we uncovered.

Gideon Analytical Laboratories received four Vishay CRCW2512220RJNEG thick film chip resistors to be analyzed. Thick film resistors are the most used resistors in electrical and electronic devices. The resistive material is a special paste with a mixture of a binder, a carrier, and the metal oxides to be deposited. These Vishay CRCW2512220RJNEG resistors thick film chip resistors feature stability at different environmental conditions and 2mm pitch packaging option for 0603 sizes. Typical applications for these chip resistors include automotive, telecommunications, and industrial. Its resistance range is 1 and 10 ohms. All of the Vishay CRCW2512220RJNEG thick film chip resistors tested open. The goal was to try to diagnose these failures.

Gideon Analytical Laboratories received six United Chemi-Con KMG series 400V 22uF 6U capacitors for the specific purpose of determining whether or not they had the presence of chlorides.

The analysis was performed using SEM-EDS. The SEM-EDS system gave elemental analysis in relation to the intensity of the element at a specific wavelength or energy level (Kev). SEM-EDS is an analytical technique used for the elemental analysis or chemical characterization of a sample. It relies on an interaction of some source of X-ray excitation and a sample. Its characterization capabilities are due in large part to the fundamental principle that each element has a unique atomic structure allowing a unique set of peaks on its electromagnetic emission spectrum.Theelectron-volt is used to measure energy. It is defined as the amount of energy an electron gains after being accelerated by 1 volt of electricity.

Gideon Analytical Laboratories received 22 EEPROM devices for analysis of the lead plating. EEPROM stands for electrically erasable programmable read-only memory and is a type of non-volatile memory used in computers and other electronic devices to store relatively small amounts of data but allowing individual bytes to be erased and reprogrammed. EEPROMs are organized as arrays of floating-gate transistors. EEPROMs can be programmed and erased in-circuit, by applying special programming signals. Originally, EEPROMs were limited to single byte operations which made them slower, but modern EEPROMs allow multi-byte page operations. Unlike EPROM chips, EEPROMs do not need to be removed from the computer to be modified. However, an EEPROM chip has to be erased and reprogrammed in its entirety, not selectively. It also has a limited life - that is, the number of times it can be reprogrammed is limited to tens or hundreds of thousands of times. EDS analysis was conducted on all of the EEPROM devices we received.

Gideon Analytical Laboratories received two metal castings. One was a cylinder and the other was an insert to the bottom of the cylinder. Metal means a process, in which liquid metal is poured into a mold, that contains a hollow cavity of the desired shape, and then allowed to cool and solidify. The solidified part is also known as a casting, which is ejected or broken out of the mold to complete the process. Traditional techniques include lost-wax casting, plaster mold casting and, sand casting. The modern casting process is subdivided into two main categories: expendable and non-expendable casting. There was some form of contamination on the two metal castings that were received, and the goal was to determine what it was.

Gideon Analytical Laboratories received two power supply boards with components. The supplies were thought to have contamination, possibly bromine, causing corrosion or failing the electrolytic capacitor. The term electrolytic capacitor in a generic term for three different capacitors, which include aluminum electrolytic capacitors, tantalum electrolytic capacitors, and niobium electrolytic capacitors. All electrolytic capacitors are polarized capacitors whose anode is made of a particular metal on which an insulating oxide layer forms by anodization, acting as the dielectric of the electrolytic capacitor. Electrolytic capacitors may corrode if used or stored in a place where they encounter acidic toxic gases, like hydrogen sulfide, sulfurous acid, nitrous acid, chlorine, or bromine.

Gideon Analytical Laboratories received two image sensors with high impedance on the connector between pins 4 and 5, measuring 10 KHz. An image sensor or imaging sensor is a sensor that detects and conveys the information that constitutes an image. It does so by converting the variable attenuation of light waves (as they pass through or reflect off objects) into signals, small bursts of current that convey the information. The waves can be light or other electromagnetic radiation. Image sensors are used in electronic imaging devices of both analog and digital types, which include digital cameras, camera modules, medical imaging equipment, night vision equipment such as thermal imaging devices, radar, sonar, and others. kHz stands for kilohertz (10³ Hz). Hertz is the unit of frequency in the International System of Units (SI) and is defined as one cycle per second.It is named for Heinrich Rudolf Hertz, the first person to provide conclusive proof of the existence of electromagnetic waves. The goal was to analyze these sensors and identify the cause of increasing resistance.

Gideon Analytical Laboratories received a Printed Circuit Board (PCB) with contamination on several capacitor sleeves, connector pins, and an oscillator. An electrolytic capacitor is a capacitor whose anode (+) consists of pure aluminum foil with an etched surface, covered with a uniformly very thin barrier layer of insulating aluminum oxide, which operates as a dielectric. The electrolyte, which covers the rough surface of the oxide layer, operates as the second electrode, the cathode (-). E-caps have the largest capacitance values per unit volume compared to the two other main conventional capacitor families, ceramic and plastic film capacitors, but much smaller capacitance than similarly sized supercapacitors. Aluminum electrolytic capacitors are divided into three subfamilies by the type of electrolyte. There are non-solid (liquid, wet) aluminum electrolytic capacitors, solid manganese dioxide aluminum electrolytic capacitors, and solid polymer aluminum electrolytic capacitors. Basic parts to an electrolytic capacitor include anode foil, a dielectric, cathode foil, cathode oxide layer, non-solid electrolyte, paper spacer, conducting polymer, among other materials. An electronic oscillator is an electronic circuit that produces a periodic, oscillating electronic signal, often a sine wave or a square wave. Oscillators convert direct current (DC) from a power supply to an alternating current (AC) signal. They are widely used in many electronic devices. The goal was to identify the contamination on the capacitor sleeves, connector pins, and an oscillator.

Gideon Analytical Laboratories received four Vishay SS26 Surface Mount Schottky Barrier Rectifiers for possible premature conditions to failure. A Schottky barrier is a potential energy barrier for electrons formed at a metal-semiconductor junction. Schottky barriers have rectifying characteristics, suitable for use as a diode. These Vishay SS26 Surface Mount Schottky Barrier Rectifiers feature a low profile package, high surge capability, and are RoHS compliant. The diodes came from PCB P/N 170310142001 Rev A03 S/N 051208-231. Positions D8, D9, D18, and D27 were identified as possible trouble spots. The goal was to determine the cause of failure.

Gideon received several Vishay SS26 Schottky rectifiers for failure analysis. It was thought something within the manufacturing process caused the devices to have a premature end of life in what would be considered a non-stressful application.

The Schottky diode is what is called a majority carrier device. It has advantages in terms of speed because it does not rely on holes or electrons recombining when they enter the opposite type of region as in the case of a conventional diode. When making the devices small, the normal RC type time constants can be reduced, making these diodes an order of magnitude faster than the conventional PN diodes. This is the prime reason why they are used in radio frequency applications.

Gideon Analytical Laboratories received several screws to identify whether or not they were the source of carbon disulfide and sulfur dioxide, which were attacking some Buna-N O-rings.  O-rings are a mechanical gasket in the shape of a torus; it is a loop of elastomer with a round cross-section, designed to be seated in a groove and compressed during assembly between two or more parts, creating a seal at the interface. The O-ring may be used in static applications or in dynamic applications where there is relative motion between the parts and the O-ring. Dynamic examples include rotating pump shafts and hydraulic cylinder pistons. Nitrile, also commonly referred to as Buna-N or NBR, is a copolymer of Acrylonitrile and Butadiene. Nitrile is the most commonly used elastomeric material for molded and extruded products. This material offers relatively low cost, good mechanical properties, and resistance to many common oils, fuels, and lubricants. NBR has poor resistance to weathering, sunlight, and ozone so it is best used in enclosed environments where parts are not exposed to the elements. For this job, the goal was to identify the source of the carbon disulfide and sulfur dioxide that was on the screws.

Gideon Analytical Laboratories received a printed circuit board (PCB) with suspected failing multi-layered ceramic capacitors (MLCC). Multilayer ceramic capacitors are fixed value capacitors in which ceramic the material acting as the dielectric. It is made up of two or more alternating layers of ceramic and a metal layer acting as the electrodes. There are various types of materials that could function as the dielectric in a capacitor, for example, glass, porcelain, paper, or mica. Each PCB has four suspected failing MLCCs, and the goal was to determine the cause of these failures.

Gideon Analytical Laboratories received two valves with failed printed circuit boards (PCBs) and corrosion inside the housing. The goal was to determine what the corrosion was and why the PCB failed. A printed circuit board mechanically supports and electrically connects electronic components using conductive trace lines, pads and other features etched from copper sheets laminated onto a non-conductive substrate. The boards are made from glass reinforced plastic with copper tracks in the place of wires. Components are fixed in position by drilling holes through the board, locating the components and then soldering them in place. The copper tracks link the components together forming a circuit. PCBs are used in all but the simplest electronic products. They are a quintessential part of the electronics industry. With decades of experience working with PCBs and advanced knowledge in electrical engineering and chemistry, this proved to be a case that was easy to solve.

GideonAnalytical Laboratories received several Printed Circuit Boards (PCBs) that were experiencing delamination of the solder masks, specifically on the EMI filter card. A PCB mechanically supports and electrically connects electronic components using conductive tracks, pads and other features etched from copper sheets laminated onto a non-conductive substrate. Components (e.g. capacitors, resistors or active devices) are generally soldered on the PCB. Advanced PCBs may contain components embedded in the substrate. Electromagnetic interference (EMI), also called radio-frequency interference (RFI) when in the radio frequency spectrum, is a disturbance generated by an external source that affects an electrical circuit by electromagnetic induction, electrostatic coupling, or conduction.The disturbance may degrade the performance of the circuit or even stop it from functioning. In the case of a data path, these effects can range from an increase in error rate to a total loss of the data.

Gideon Analytical Laboratories received two PCB assemblies upon which were several failing Vishay CRCW1210-HP-e3 surface mount (SM) resistors. Surface mount technology (SMT) is a method for producing electronic circuits in which the components are mounted or placed directly onto the surface of printed circuit boards (PCBs). An electronic device so made is called a surface-mount device (SMD). In the industry, it has largely replaced the through-hole technology construction method of fitting components with wire leads into holes in the circuit board. The goal was to determine the cause of the failing Vishay CRCW1210-HP-e3 SM resistors.

Gideon Analytical Laboratories received several lighting tracks for failure analysis. They all had what appeared to be arcing which caused severe copper pitting, melting of the Noryl, and distortion of the power bus bar. The neutral bus was also pitted but not nearly as bad as the power rail. Electrical arcing is an electrical breakdown of a gas that produces an ongoing electrical discharge. The current through a normally non-conductive medium such as air produces a plasma; the plasma may produce visible light. An arc discharge is characterized by a lower voltage than a glow discharge, and it relies on thermionic emission of electrons from the electrodes supporting the arc. An arc between two electrodes can be initiated by ionization and glow discharge, as the current through the electrodes is increased. The breakdown voltage of the electrode gap is a function of the pressure, the distance between electrodes and the type of gas surrounding the electrodes. When an arc starts, its terminal voltage is much less than a glow discharge, and current is higher. An arc in gases near atmospheric pressure is characterized by visible light emission, high current density, and high temperature. NORYL resins are a rare example of a homogeneous mixture of two polymers. Most polymers are incompatible with one another, so tend to produce separate phases when mixed. The two polymers compatibility in NORYL resins is due to the presence of a benzene ring in the repeat units of both chains. The goal was to determine why there was electrical arcing on these lighting tracks.