Wet Chemical Analyzers

2001 ◽  
pp. 3209-3213
Author(s):  
A.R.J. David
Keyword(s):  
Author(s):  
Pratibha L. Gai ◽  
M. A. Saltzberg ◽  
L.G. Hanna ◽  
S.C. Winchester

Silica based ceramics are some of the most fundamental in crystal chemistry. The cristobalite form of silica has two modifications, α (low temperature, tetragonal form) and β (high temperature, cubic form). This paper describes our structural studies of unusual chemically stabilized cristobalite (CSC) material, a room temperature silica-based ceramic containing small amounts of dopants, prepared by a wet chemical route. It displays many of the structural charatcteristics of the high temperature β-cristobalite (∼270°C), but does not undergo phase inversion to α-cristobalite upon cooling. The Structure of α-cristobalite is well established, but that of β is not yet fully understood.Compositions with varying Ca/Al ratio and substitutions in cristobalite were prepared in the series, CaO:Al2O3:SiO2 : 3-x: x : 40, with x= 0-3. For CSC, a clear sol was prepared from Du Pont colloidal silica, Ludox AS-40®, aluminium nitrate nonahydrate, and calcium nitrate hexahydrate in proportions to form a final composition 1:2:40 composition.


2020 ◽  
Author(s):  
Mikhail Trought ◽  
Isobel Wentworth ◽  
Timothy Leftwich ◽  
Kathryn Perrine

The knowledge of chemical functionalization for area selective deposition (ASD) is crucial for designing the next generation heterogeneous catalysis. Surface functionalization by oxidation was studied on the surface of highly oriented pyrolytic graphite (HOPG). The HOPG surface was exposed to with various concentrations of two different acids (HCl and HNO3). We show that exposure of the HOPG surface to the acid solutions produce primarily the same -OH functional group and also significant differences the surface topography. Mechanisms are suggested to explain these strikingly different surface morphologies after surface oxidation. This knowledge can be used to for ASD synthesis methods for future graphene-based technologies.


Author(s):  
D. Zudhistira ◽  
V. Viswanathan ◽  
V. Narang ◽  
J.M. Chin ◽  
S. Sharang ◽  
...  

Abstract Deprocessing is an essential step in the physical failure analysis of ICs. Typically, this is accomplished by techniques such as wet chemical methods, RIE, and mechanical manual polishing. Manual polishing suffers from highly non-uniform delayering particularly for sub 20nm technologies due to aggressive back-end-of-line scaling and porous ultra low-k dielectric films. Recently gas assisted Xe plasma FIB has demonstrated uniform delayering of the metal and dielectric layers, achieving a planar surface of heterogeneous materials. In this paper, the successful application of this technique to delayer sub-20 nm microprocessor chips with real defects to root cause the failure is presented.


Author(s):  
Huixian Wu ◽  
Arthur Chiang ◽  
David Le ◽  
Win Pratchayakun

Abstract With gold prices steadily going up in recent years, copper wire has gained popularity as a means to reduce cost of manufacturing microelectronic components. Performance tradeoff aside, there is an urgent need to thoroughly study the new technology to allay any fear of reliability compromise. Evaluation and optimization of copper wire bonding process is critical. In this paper, novel failure analysis and analytical techniques are applied to the evaluation of copper wire bonding process. Several FA/analytical techniques and FA procedures will be discussed in detail, including novel laser/chemical/plasma decapsulation, FIB, wet chemical etching, reactive ion etching (RIE), cross-section, CSAM, SEM, EDS, and a combination of these techniques. Two case studies will be given to demonstrate the use of these techniques in copper wire bonded devices.


Author(s):  
Dongmei Meng ◽  
Joe Rupley ◽  
Chris McMahon

Abstract This paper presents decapsulation solutions for devices bonded with Cu wire. By removing mold compound to a thin layer using a laser ablation tool, Cu wire bonded packages are decapsulated using wet chemical etching by controlling the etch time and temperature. Further, the paper investigates the possibilities of decapsulating Cu wire bonded devices using full wet chemical etches without the facilitation of laser ablation removing much of mold compound. Additional discussion on reliability concerns when evaluating Cu wirebond devices is addressed here. The lack of understanding of the reliability of Cu wire bonded packages creates a challenge to the FA engineer as they must develop techniques to help understanding the reliability issue associated with Cu wire bonding devices. More research and analysis are ongoing to develop appropriate analysis methods and techniques to support the Cu wire bonding device technology in the lab.


Author(s):  
Huixian Wu ◽  
James Cargo ◽  
Huixian Wu ◽  
Marvin White

Abstract The integration of copper interconnects and low-K dielectrics will present novel failure modes and reliability issues to failure analysts. This paper discusses failure modes related to Cu/low-K technology. Here, physical failure analysis (FA) techniques including deprocessing and cross-section analysis have been developed. The deprocessing techniques include wet chemical etching, reactive ion etching, chemical mechanical polishing and a combination of these techniques. Case studies on different failure modes related to Cu/low k technology are discussed: copper voiding, copper extrusion; electromigration stress failure; dielectric cracks; delamination-interface adhesion; and FA on circuit-under-pad. For the cross-section analysis of copper/low-K samples, focused ion beam techniques have been developed. Scanning electron microscopy, EDX, and TEM analytical analysis have been used for failure analysis for Cu/low-K technology. Various failure modes and reliability issues have also been addressed.


Sign in / Sign up

Export Citation Format

Share Document