Characterization, electrical

To a very large extent, procedures from printed-circuit board technology can be applied for characterizing the electrical properties of assembled MID. An overview of the mainstream analog and digital methods of measurement is given in [25], for example. Once again, however, provision has to be made for some specifics of practical application of these methods to MID. 

Measurement of ohmic resistance is a basic test method in many sectors of eiectron-ics production as a means of checking  

The most frequentiy used methods are two-point and four-point measurement. These two methods are compared in Fig. 6.14. 

Four-point measurement makes for higher precision. By contrast with two-point measurement, this method separates power suppiy and resistance measurement by the voitage drop. With an imposed constant current flow, the four-conductor arrangement aiiows voitage drop to be measured virtuaiiy without current and so to a very iarge extent independentiy of contact resistance and iine resistance. 

In both methods the sample is contacted manually or automatically by fine metallized probes. The probes can be firmly set at the appropriate positions in an adapter, or else guided and positioned individually in a flying probe test. An important point to be kept in mind when testing metallizations on MID is that care is necessary to prevent sharp tips of probes from damaging the surface of the thin conductors on the soft plastic substrates. Using spring-mounted probes is one way of avoiding this risk. 

In this section only experimental results are summarized. For theoretical considerations compare Chapter 7 of this book by Horowitz and Delannoy [32]. 

Enhancing the catalysis at the surface of PEC electrodes results in a lower kinetic overpotential and an increase in photocurrent. The effectiveness of the catalysts after surface treatment can be determined by utilizing three-electrode j-V measurements (see Section Three-Electrode j-V and Photocurrent Onset ) as well as IPCE measurements (see Chapter Incident Photon-to-Current Efficiency and Photocurrent Spectroscopy ). It may also useful to perform Mott-Schottky (see Section Mott-Schottky ) to determine any impacts these catalysts may have on the band structure (e.g., due to Eermi level pinning). 

Another important phenomenon to be checked is the leakage current of shallow junction diodes. The leakage current provides valuable information about the quality of the Si-W interface and whether unallowed amounts of silicon are consumed during the selective tungsten deposition process. Again, one can expect that blanket tungsten gives less problems here because of the presence of the adhesion-barrier layer. 

When characterizing such electrical parameters, it is of utmost importance to do the evaluation as accurately as possible and to use the appropriate control experiments. Some examples of what errors can be made 

The stability of the tungsten-silicon interface with respect to silicon diffusion and electrical integrity has been reported to be in the range 450-600°C [Joshi et al.107, Shioya et al.108, Pauleau et al.109, Thomas et al.110]. This is very compatible with Al alloy temperatures (400-450°C) in VLSI processes. 

The compatibility of the H2/WF6 chemistry with silicides is problematic for TiSi2, PtNiSi [Broadbent et al.111] and CoSi2 [van de Putte et al.112]. Problems such as Si extraction and void formation have been observed. In contrast, the milder SiH4/WF6 chemistry shows good results on such silicides [Etlwanger et al,14]. 

Contact reliability When doing reliability studies one has to take care that the sample size (ie. the number of contacts or vias) is sufficiently large in order to come to statistically meaningful conclusions. The normal way to do this is by using chains in which thousands of contacts or vias are connected. For contact chains or strings this can, depending on how exactly the 

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Fig. 6. Electrical characterization of (a) SiGe nanocrystals (b) Ni nanocrystals embedded in HfD2 from MOS capacitors.

This section treats the plasma physics and plasma chemistry of the typical silane-hydrogen RF discharge, with occasional examples that employ a somewhat higher excitation frequency. Electrical characterization of the discharge is followed by an analysis of the silane chemistry. An appropriate set of gas phase species is presented, which are then used in the modeling of the plasma. A comparison is made between modeling results and experimental work in ASTER. Extension to 2D modeling is presented as well. 

High quality one-dimensional copper sulfide (CuS) nanorods (50-200 nm) have been demonstrated using template assisted electrochemical deposition, a sonoelec-trochemical method. Thus generated nanorods were also electrically characterized as p-type semiconductors [64]. In this process, ultrasound assists the electrochemical deposition by the combination of any of the following three processes ... 

The light-emission characteristics of a white-light-emitting EL device with a doubly doped ZnS Pr,Ce,F phosphor layer have been described. It was observed that optimization of the co-doping of Ce enhances the emission characteristics compared to an EL device with a singly doped ZnS Pr,F layer.22 An electrical characterization of Ce-doped ZnS TbOF EL thin films has been reported Ce doping was seen to improve the radiative emission efficiency leading to improved performance of Ce co-doped film.23... 

Chiechi RC, Weiss EA, Dickey MD, Whitesides GM (2008) Eutectic gallium-indium (EGaln) a moldable liquid metal for electrical characterization of self-assembled monolayers. Angew Chem Int Ed 47(1)442-144... 

Shibata, T. Muranushi, Y. Miura, T. Kishi, T. 1991. Electrical characterization of 2H-SnS2 single crystals synthesized by the low temperature chemical vapor transport method. J. Phys. Chem. Solids 52 551-553. 

Deen, M. Kazemeini, M. Haddara, Y. Yu, J. Vamvounis, G Holdcroft, S. Woods, W. 2004. Electrical characterization of polymer-based FETs fabricated by spin-coating poly(3-alkylthiophene)s. IEEE Trans. Electronic Dev. 51 1892-1901. 

Single-Target Synthesis and Detailed Electrical Characterization... 

Flow in Microfluidic Reactors 7.4. Solid-State Electrical Characterization of 4487... 

Solid-State Electrical Characterization of Conformal, Ultrathin Polymer Dielectrics... 

T. Park, T. Tugbawa, D. Boning, J. Chung, S. Hymes, R. Muralidhar, B. Wilks, K. Smekalin, and G. Bersuker, Electrical Characterization of Copper Chemical Mechanical Polishing, Proc. CMP-MIC, Santa Clara, CA, Feb. 1999,... 

Chang, H., Ikram, A., Kosari, F., Vasmatzis, G., Bhunia, A., and Bashir, R. (2002). Electrical characterization of micro-organisms using microfabricated devices. /. Vac. Sci. Technol. B 20, 2058-2064. 

Muck T, Wagner V, Bass U, Leufgen M, Geurts J, Molenkamp LW (2004) In situ electrical characterization of DH4T field-effect transistors. Synth Met 146 317-320... 

The surface properties of alkanethiol SAMs have been studied thoroughly, and recently people have performed electrical characterizations and found the conduction mechanism through such self-assembled alkanethiol monolayers is tunneling due to its large HOMO-LUMO gap (HOMO highest occupied molecular orbital, LUMO lowest unoccupied molecular orbital) (>8 eV).28 Another type of molecular system is the so-called... 

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