Inspection incoming

For a typical production run, the materials inspection group would obtain a sample of five parts per lot. The entire lot of parts would then be quarantined and inventoried through the use of an automated system such as a FATA system. The samples from each lot would then be sent to the material lab for analysis. Depending on the nature of the material, the chemist would determine the type of testing required, complete the test, and compare it to the material specification. Table 2.1 shows typical equipment found in the automotive chemist s lab in the plant environment. This list is meant to be a general guide to typical equipment and is not meant to be inclusive. 

DSC-TGA (differential scanning calorimetry-thermal gravimetric analysis) 

Analysis of manufacturing system chemicals as well as surface analysis 

General system analysis, paints, coolants, hydraulics, etc. 

Adsorption of radiation Scattering of radiation Refraction of radiation Diffraction of radiation Rotation of radiation Electrical potential Electrical current Electrical resistance Mass to charge ratio Rate of reaction Thermal properties Mass Volume 

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A characteristic of the analytical requirement at the incoming inspection stage is the accuracy of the results, because these are frequently exchanged between the vendor and the purchaser, and become the subject of financial negotiation. Raw materials include iron ore, ferrous alloys and raw iron, but also casting aids, refractories, as well as lubricating oils, fats and fuels... 

Gitis N, Vinogradov M. Incoming inspection and failure analysis of CMP consumables at the semiconductor fab. VMIC Conference Santa Clara, CA 2003. 

An Instron tensile machine can be used to measure stress and strain in the automotive lab. However, incoming inspection at a supplier is generally where this type of analysis takes place. More often, an automotive chemist at an OEM will be required to analyze a sample for failure analysis of that particular part. A thermogravimetric analyzer (TGA) will measure the change in mass of an elastomer in an inert (nitrogen) atmosphere as the temperature is waived. These instruments are very precise and will give information such as degradation temperature, filler content solvent residue, and absorbed moisture content. 

With the increasing intensification of quality assurance measures before (incoming inspection, FMEA) and during manufacture (cleanliness tests), the use of filter equipment is declining or limited to a protective function ( policing filtration ). 

Establish Threshold. At least 50% of available technician time will be spent providing equipment maintenance support services (revolving equipment problems and scheduled IPMs). At least 25% of available technician time will be spent providing equipment management support services (installations, acceptance testing, incoming inspections, equipment inventory database management, and hazard notification review). 

Roll tester A. The first machine is located in an elevator s company laboratory and it is used for verification of gears in the incoming inspection area. 

The acquisition of equipment is the next major part of effective equipment management. It follows and is indeed part of the equipment planning phase. Flowing from definition of requirements, specifications are developed. Bas on those specifications, a subset of possible equipment is evaluated for conformance to the specifications or standards, and purchase of the most appropriate equipment is initiated. When the equipment arrives at the hospital, the acceptance or incoming inspection of the equipment is a very common function that clinical engineering fulfils. 

At the foundry level, quality control tests may be performed diuing incoming inspection of the ceramic materials. Finished-product inspection may range from limited testing (e.g., shorts and opens to ensure that the product was built to print) to additional functional performance testing on each substrate. Test coupons on each panel may be used for electrical performance checks (e.g., impedance, resistance), and destructive mechanical tests for feature size conformance. The extent of testing at this level is determined by the functional complexity of the circuits, final assembly testing, and economics. 

Another important use of the viscometer is in controlling the paste-thinning process. From time to time, it is necessary to add thinner to the paste to replace that portion lost to evaporation. If the viscosity is measured at incoming inspection and recorded as part of the acceptance process, it is a relatively simple process to add sufficient thinner to return it to the original viscosity. 

Quality Poor-quality products are found during incoming inspection Total number of rejected items are arrived from supplier in each batch... 

Rdiability of semiconductor devices is determined by two considerations. The first one is early failures, usually caused by fluctuations in production, and the second one is fatigue, related to package design. Accelerated tests are necessa to detect those failures earlier. Many test methods have been proposed for development and assurance on the manufacturer s side and for incoming inspection on the user s... 

SOLDERABILITY INCOMING INSPECTION AND WETTING BALANCE TECHNIQUE... 

Plating, solderability, and soldering in the tin lead world has such a large process window that in the majority the dip and look testing suffices with defects normally in the parts per biUion. The occasional disaster does occur but it is rare and attributable to an assignable cause. This process latitude and statistical process control has resulted in the demise of the incoming inspection departments at the CM or OEM. The technician who wonld have once performed the testing has been replaced by a clerk who only job is to reconcile the pnrchase order quantity with the received qnantity. 

This chapter covers why manufacturers inspect printed circuit assemblies, how they have implemented and enhanced visual inspection, what automated inspection systems they are using, and how they have implemented these antomated systems. The scope of this chapter includes only inspection of printed circuit assemblies during the assembly process, as typically shown in Fig. 53.1. Thus, it includes inspection of solder paste after the paste printing process step, components after the component placement process step, and solder joints after the solder reflow process step. Not included, however, is incoming inspection of components and the bare printed circuit board (PCB). The focus of this chapter is on prodnction nse of inspection, not the collection of measurements dnring process development in a research and development (R D) environment. 

The basic properties of the raw materials should be guaranteed by material vendors however, it is still necessary to conduct incoming inspections by circuit manufacturers. There is less experience with the new materials developed for high-density flex circuits than with traditional materials. Physical properties and cosmetic defects should be inspected by sampling. 

The material prices summarized in this section are the prices for the materials only and do not include other expenses, such as incoming inspection charges, fees for compliance with quality control, verification of the quality and quantity of the material, cost of refining if needed, and return of the material shipment if the material did not meet the purchasing specifications. 

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