The orientation of the devices within a package determine the best chosen approach for access to a select component embedded in epoxy both in package or System in Package and multi-chip module (MCM). This article assists the analyst in making decisions on frontside access using flat lapping, chemical decapsulation, laser ablation, plasma reactive ion etching (RIE), CNC based milling and polishing, or a combination of these coupled with optical or electrical endpoint means. This article discusses the general characteristics, advantages, and disadvantages of each of these techniques. It also presents a case study illustrating the application of CNC milling to isolate MCM leakage failure.

Circuit edit has been instrumental to the development of focused ion beam (FIB) systems. FIB tools for advanced circuit edit play a major role in the validation of design and manufacture. This chapter begins with an overview of value, role, and unique capabilities of FIB circuit edit tools for first silicon debug. The etching capabilities of circuit edit FIB tools are then discussed, providing information on chemistry assisted etching in silicon oxides and low-k dielectrics. The chapter also discusses the requirements and procedures involved in edit operation: high aspect ratio milling, endpointing, and cutting copper. It then provides an introduction to FIB metal/conductor deposition and FIB dielectric deposition. Edit design rules that can facilitate prototype production from first silicon are also provided. The chapter concludes with a discussion on future trends in circuit edit technology.

With semiconductor device dimension continuously scaling down and increasing complexity in integrated circuits, delayering techniques for reverse engineering is becoming increasingly challenging. The primary goal of delayering in semiconductor failure analysis is to successfully remove layers of material in order to locate and identify the area of interest. Several of the top-down delayering techniques include wet chemical etching, dry reactive ion etching, top-down parallel lapping (including chemical-mechanical polishing), ion beam milling and laser delayering techniques. This article discusses the general procedure, types, advantages, and disadvantages of each of these techniques. In this article, two types of different semiconductor die level backend of line technologies are presented: aluminum metallization and copper metallization.

This chapter discusses the practices and procedures used to reveal and record macrostructural features such as hardening depth, weld thickness, crack size, porosity, hot folds, and machining and tooling marks. It provides information on sectioning, sample location, orientation, surface grinding, and etching. It describes macrographic etchants and the features they reveal along with common etching problems and how to avoid them. It explains how to evaluate etching results and how they can be improved using remedial processes such as light grinding. It also discusses photographic reproduction, lighting, and image enhancement techniques.

This chapter explains how to prepare material samples for optical microscopy, the most common method for characterizing the microstructure of cast iron and steel. It provides information on sectioning, mounting, polishing, etching, and recording. It describes the nature of surface roughness, the factors that contribute to it, and its effect on image quality. It discusses the use of fixturing and holding devices, includes photographic examples of polishing defects and drying marks, and provides an overview of micrographic etchants and the features they reveal. It also describes the steps involved in replicating part surfaces.

Intermetallic phase precipitates in aluminum alloys can often be identified without resorting to chemical analysis. Very often the determination can be made based on the shape, color, and refractive properties of the particular phase. This chapter explains how these visual attributes can be observed using metallographic techniques. It describes, and in many cases illustrates, the characteristic shapes, colors, and optical properties associated with aluminum alloy intermetallic phases and how they can be enhanced through selective etching. It provides an atlas of microstructures comparing the effects of selective etching procedures on various phase constituents in cast aluminum-silicon alloys. The compilation of images demonstrates the use of two types of reagents: those that reveal discontinuities in crystal orientation and grain boundaries, and those that reveal differences in chemical composition.

This chapter explains how to safely prepare beryllium alloy samples for metallographic analysis. It describes grinding, polishing, and etching procedures in detail. It also discusses the identification of major and minor constituents and the general appearance of beryllium microstructure.

This chapter discusses the important aspects that a metallographer should understand in order to effectively reveal a microstructure. It begins by exploring etching response and how it can be a tool for revealing various microstructural features. The next part of the chapter discusses methods for revealing microstructure in the as-polished (unetched) specimen, then guidelines for selecting and using etchants when needed. The chapter discusses different types of etchants in terms of their ingredients, etching procedure, and major uses. The etchants discussed include basic etchants (nital and picral and their variations) and tint etchants for carbon and low-alloy steels and cast irons, and basic etchants for stainless steels. Finally, information is provided on different illumination methods (differential interference contrast and dark-field illumination) that can be used to highlight certain features in microstructures.

This appendix provides information on the chemical composition, method of use, and applications of various etchants used in the metallography of carbon steels.

This chapter explains how to achieve accurate, sharp delineation of the microstructure of metals using appropriate etching and contrasting techniques. It covers a variety of methods, including chemical etching, heat tinting, gas contrasting, vapor deposition, magnetic etching, ion bombardment, and dislocation etch pitting.

This appendix provides a list of etch compositions and procedures that reveal the macrostructure of aluminum, beryllium, bismuth, antimony, cobalt, copper, lead, magnesium, nickel, tin, titanium, zinc, and their respective alloys as well as iron, steel, noble metals, refractory metals, silicon, zirconium, and hafnium.

This appendix lists copper-containing macroetchants that are used on iron and steel.

This appendix lists etch compositions and procedures that reveal strain patterns in aluminum and nickel-base superalloys.

This appendix contains tables that list the composition and capabilities of etchants that reveal the microstructure of metals and alloys, including aluminum, chromium, cobalt, copper, lead, magnesium, molybdenum, nickel, niobium, palladium, platinum, radioactive metals, rare earth metals, rhenium, rhodium, selenium, tellurium, silicon, silver, tantalum, tin, titanium, tungsten, vanadium, and zinc, as well as carbides, oxides, and nitrides.

This appendix is a list of etchants that are used to reveal dislocations in various metals, alloys, and compounds.