Sicut tabellarius variarum partium et centrum circuii signum tradendi; PCB Praecipua et praecipua pars productorum electronicarum notitiarum facta est, eius qualitas et fides planities qualitatem et fidem totius instrumenti determinat. Tamen, propter sumptus et rationes technicas, multum sunt problemata defectiva in PCB productione et applicatione.

Ad huiusmodi problema defectio, quibusdam technicis analysi defectionis communiter adhibitis, ad curandum qualitatem et constantiam gradus PCB in fabricandis. Haec charta decem analysin analysin defectus summat ad referendum.

Mechanismus et causa analysis PCB defectionis

1. A visual inspectionem

Inspectio aspectus est visibiliter inspicere vel uti quibusdam instrumentis simplicibus, ut microscopio stereoscopico, microscopio metallographico vel etiam vitreo magnificando, ad reprimendam speciem PCB et partes incassum inveniendas et argumenta physica pertinentia. Praecipuum munus est defectum collocare et praeiudicialiter iudicare modum defectum PCB. Visus inspectio maxime impedit PCB pollutionis, corrosionis, situm tabulae explosionis, ambitus wiring et regularitatis defectum, si massa sit vel individua, sive semper in quadam area contracta, etc. In addition, the failure of many PCBS was discovered after the assembly of PCBA. Whether the failure was caused by the influence of the assembly process and materials used in the process also requires careful examination of the characteristics of the failure area.

2. X-ray fluoroscopia

Aliquot partes quae per speciem inspici non possunt, tum intus PCB per foramen et alia vitia interna, adhibenda est systema fluoroscopia X-radii ad reprimendum. Systema fluoroscopia X-radius est usus diversae crassitudinis materialis vel diversae densitatis materialis hygroscopicitatis X-radii vel transmissionis diversorum principiorum ad imaginationem. Haec technologia magis ad reprimendam locum defectuum in PCBA compagibus solidioribus, per defectus et defectus foraminis in BGA vel CSP machinis cum magna densitate packaging. At present, the resolution of industrial X-ray fluoroscopy equipment can reach less than one micron, and is changing from two dimensional to three dimensional imaging equipment. There are even five dimensional (5D) equipment used for packaging inspection, but this 5D X-ray fluoroscopy system is very expensive, and rarely has practical application in the industry.

3. Sectio analysis

Scalpere analysis est processus obtinendi PCB sectionis transversalis structuram per sampling, Mosaicum, scalpere, expolitio, corrosio, animadversio et series modorum et gradus. Abundantia notitia de microstructure PCB (per foramen, tunica, etc.) obtineri potest per analysis scalpere, quae bonum fundamentum praebet ad emendationem proximam qualitatem. However, this method is destructive, once the slice is carried out, the sample will inevitably be destroyed; Eodem tempore, methodus sample requisita alta, temporis praeparatio specimen longum est, necessitas ad personas technicas erudiendas perficiendas. For detailed slicing procedures, please refer to IPC standards IPC-TM-650 2.1.1 and IPC-MS-810.

4. Scanning acusticus microscopii

At present, c-mode ultrasonic scanning acoustic microscope is mainly used for electronic packaging or assembly analysis. It makes use of the amplitude, phase and polarity changes generated by the reflection of high-frequency ultrasound on the discontinuous interface of materials to image, and its scanning mode is to scan the information in the X-Y plane along the Z-axis. Therefore, scanning acoustic microscopy can be used to detect various defects, including cracks, delamination, inclusions, and voids, in components, materials, and PCB and PCBA. Internal defects of solder joints can also be directly detected if the frequency width of scanning acoustics is sufficient. Of a typical scanning acoustic image in color red alert said defects exist, because a large amount of plastic packaging components used in SMT process, by a lead into the process of lead-free technology, a large number of moisture reflow sensitive problem, namely the moisture absorption of powder coating devices will be at a higher temperature reflow lead-free process occurs within or substrate layer cracking phenomenon, Under the high temperature of lead-free process, common PCB will often burst board phenomenon. In hoc puncto, microscopio acusticus scandens specialem utilitatem suam ostendit in nondestructive deprehensio multi- strati altae densitatis PCB. The general obvious bursting plate can be detected by visual inspection.

5. Microinfrared analysis

Micro analysis infrared est, spectroscopio ultrarubrum cum analysi microscopio coniuncto methodo, uti varia materia (maxime organica materia) in principio spectri infrarubri effusio, compositionem materiae compositam, cum microscopio copulatam, lucem visibilem et infrarubrum efficere potest. cum lumine viae, dummodo sub agro visuali, quaerere potest analysin vestigii organici pollutantium. Absente microscopio, spectroscopium ultrarubrum plerumque solum magna exemplaria resolvere potest. In many cases, trace pollution in electronic process can lead to poor weldability of PCB pad or lead pin. It can be imagined that it is difficult to solve the process problem without the matching infrared spectrum of microscope. The main use of microscopic infrared analysis is to analyze the organic pollutants on the welding surface or solder spot surface, and analyze the causes of corrosion or poor solderability.

6. Microscopium analysis

Microscopium electronicum (SEM) unum est utilissimum magnarum electronicarum microscopicarum imaginum systemata pro defectu analysi. Eius opus principium est electronico trabem cum diametro decem ad millia angstromorum formare (A) ponendo electronici trabem e cathode anodam acceleratam emissam. Actio claudicatio est lustrans; Electron trabes superficies exempli punctum per punctum certo tempore et ordine lustrat. Summus industria electronica trabes bombardas superficiei exempli et varias informationes generat, quae colligi et ampliari possunt ut varias res graphicas in ostentatione velamento comparare possint. The excited secondary electrons are generated within the range of 5 ~ 10nm on the surface of the sample. Therefore, the secondary electrons can better reflect the surface topography of the sample, so they are most commonly used for morphology observation. Excitatae respersae electrons generantur in latitudine 100~Mnm in superficie exempli, et diversas notas emittunt cum differentia substantiae numeri atomici. Ideo imago electronica receptacula habet proprietates morphologicas et numerum atomorum distinctionem facultatem, et ideo imago electronica reducta distributionem elementorum chemicorum reflectere potest. Nunc microscopii electronici perceptio validissima, quaevis subtilis structura vel superficiei notae, ad centena milia temporum magnificari potest propter observationem et analysin.

In PCB or solder joint failure analysis, SEM is mainly used for failure mechanism analysis, specifically, is used to observe the surface morphology structure of the pad, solder joint metallographic structure, measurement of intermetallic compounds, solderable coating analysis and tin must be analyzed and measured. Different from the optical microscope, the scanning electron microscope produces electronic images, so it has only black and white colors. Moreover, the sample of the scanning electron microscope is required to conduct electricity, and the non-conductor and part of the semiconductor need to be sprayed with gold or carbon, otherwise the charge will gather on the surface of the sample and affect the sample observation. Praeterea profunditas agri electronici microscopii intuentis imaginem multo maior est quam microscopii optici, quae est magni momenti methodus pro analysi structurae metallographicae, fracturae microscopicae et susurrosi stagni.

7. X-ray energy spectrum analysis

Solet in microscopio electronico electronico supra dicto cum spectrometri industriae X radius instructus esse soleat. When the high-energy electron beam hit the surface, the surface material of the inner electrons in the atoms are bombarded escape, outer electrons to low energy level transition will inspire characteristic X ray, atomic energy level difference of different elements from different characteristic X ray is different, therefore, can send sample of the characteristics of X-ray as chemical composition analysis. Eodem tempore instrumenta correspondentia spectrum dispersionis spectrometri (WDS pro brevi) respective dicuntur et industria spectrometri dispersionis (EDS brevium) secundum indolem necem vel notam energiae detectionis signo X-radii. Resolutio spectrometri altior est quam spectrometri energiae, et celeritas analysis spectrometri energiae velocior est quam spectrometri energiae. Propter celeritatem altum et humile sumptus spectrometri energiae, microscopia generalis ENARRATIO spectrometris industria instructa est.

Diverso modo electronici trabes intuens, vis spectrometri punctum, lineam et planum superficiei resolvere potest, et notitias diversorum distributionis elementorum obtinere.Point analysis yields all elements of a point; Linea Analysis One analysis elementum singulis temporibus certa linea conficitur, et linea rerum omnium distributio multiplici inspiciendo obtinetur. Superficies Analysis Omnium elementorum in data superficie Analysis. Contentum elementum mensuratum mediocris mensurae superficiei est.

In the analysis of PCB, energy dispersive spectrometer is mainly used for the composition analysis of pad surface, and the elemental analysis of contaminants on the surface of pad and lead pin with poor solderability. Analysis quantitatis accurate spectrometri energiae limitatur, et contentum minus quam 0.1% plerumque non facile deprehendes. Compositio spectri energiae et SEM notitias morphologiae superficiei et compositionis simul consequi possunt, quae causa est cur late adhibeantur.

8. Photoelectron spectroscopium (XPS) analysis

Exempla per X radium irradiatio, superficies corticis interioris atomi e servitute nuclei et superficiei solidae efformantis effugiet, suam motu energiam metiendam Ex, testa interior electrons atomi energiam ligatricem obtineri potest. Eb, Eb ex diversis elementis et diversis electronicis concha variata, est “digiti” identitatis parametri atomi, formatio lineae spectris est photoelectron spectroscopii (XPS). XPS adhiberi potest pro analysi qualitativa et quantitativa elementorum in superficie levi (pluribus nanometris) superficiei exempli. Praeterea informationes de chemicis statuum elementorum valentia ex chemicis mutationibus energiae ligandi haberi potest. Indicium dare potest vinculi inter statum vale- tudinis superficiei et circa elementa. The incident beam is X-ray photon beam, so insulation sample analysis can be carried out, without damaging the analyzed sample rapid multi-element analysis; Multilayers etiam longitudinaliter per argon ion denudationem (vide casum infra) explicari possunt multo maiore sensibilitate quam spectrum energiae (EDS). XPS maxime adhibetur in analysi PCB analysi qualitatis, pollutionis analysi et oxidationis gradus analyseos, ad determinandam altam rationem pauperis weldability.

9. Differential Scanning Calorim-etry

Methodus metiendi differentiam in potentia input inter substantiam et relationem substantiae ut functionem caliditatis (vel temporis) sub temperationis programmatis potestate. DSC is equipped with two groups of compensation heating wire under the sample and reference container, when the sample in the heating process due to the thermal effect and reference temperature difference δ T, through the differential heat amplifier circuit and differential heat compensation amplifier, so that the current flowing into the compensation heating wire changes.

The temperature difference δ T disappears, and the relationship between the difference of the thermal power of the two electrically compensated samples and the reference material with temperature (or time) is recorded. According to this relationship, the physicochemical and thermodynamic properties of the material can be studied and analyzed. DSC is widely used in PCB analysis, but is mainly used to measure the curing degree of various polymer materials used in PCB and glass state transformation temperature, these two parameters determine the reliability of PCB in the subsequent process.

10. Thermomechanical analyzer (TMA)

Analysis mechanica mechanica adhibetur ut metiatur deformatio proprietatum solidorum, liquorum et rum sub viribus thermalibus vel mechanicis sub moderamine temperaturae programmatis. Communiter usus onus modi comprehendunt compressionem, acum insertionem, extensionem, flexionem, etc. Testium specillum in trabi cantileveri et fontis helici fulcimento fixum consistit, per motorem oneris applicati, cum speciminis deformatio occurrit, transformator differentialis ad mutationem detegendam, et una cum notitia processus, ut temperies, accentus et eliquatio. materia obtineri potest sub contemptibili onere deformationis relationum cum temperie (vel tempore). Secundum relationem inter deformationem et temperiem (vel tempus), physica et thermodynamica materiae proprietates considerari et exponi possunt. TMA late in analysi PCB adhibetur ac maxime adhibetur in metiendis duobus parametris criticis PCB: expansio linearis coefficiens et temperatus transitus vitreus. PCB cum dilatatione nimis ampla coefficiente saepe ad fracturam foraminum metalla- rum perducunt post glutino et conventum.