Metallic features

When building clusters by coating the fullerenes with metal, features similar to the electronic and geometric shells found in pure metal clusters[9] are observed in the mass spectra. In the case of fullerene molecules coated with alkaline earth metals (section 3), we find that a particularly stable structure is formed... 

Photothermal decomposition of palladium acetate by scanned cw Ar+ laser irradiation produces metal features that exhibit pronounced periodic structure as a function of laser power, scan speed, substrate and beam diameter, as shown in Figures 3 and 4. The periodic structure is a function of the rate at which the film is heated by absorption of the incident laser radiation coupled with the rate at which the heat of the decomposition reaction is liberated. This coupling generates a reaction front that outruns the scanning laser until quenched by thermal losses, the process to be repeated when the laser catches up and reaches unreacted material. Clearly, such a thermal process is also affected by the thermal conductivity of the substrate, the optical absorption of the substrate in those cases where the overlying film is not fully absorbing,... 

A number of works have focused on the pattern dependencies in tungsten (both tungsten via and local interconnect) polishing [12,19,21]. To first order, empirical results seem to suggest that dishing is dominated by the width or size of the metal feature being polished wide lines tend to suffer... 

In addition to erosion, an interesting model for dishing within metal features is proposed, based on the concept of a maximum dishing, which... 

The switching or memory phenomena induced by electric field application or photo irradiation have been studied on Mott insulators, charge ordered insulators, and N-I transition systems and were found to be fast phase transitions in general. For the former two systems, the phase transitions caused a pronounced change in reflectance and conductivity from insulating to metallic features. The third system also exhibited a change in conductivity and dielectric response connected with the transports of solitons and/or domain walls, dynamic dimerization, and... 

The most important aspect of titanium is its high resistance to oxidizability. Generally, titanium is resistant to common oxidizing solutions. The metal is attacked by dry chlorine gas and introduction of 1 % of water into chlorine medium results in preventing the attack of the metal. Features relevant to particular environments are as follows ... 

In the academic setting, inkjet resolution reported for printed organic electronic materials is approximately 20-25 Lxm for untreated substrates and 5 p,m for thermal laser printing. For conductive metallic features, features of 10 Lxm or less have been reported for untreated surfaces. These limits can be further reduced by pretreating the substrate, for example by creating hydrophobic/ hydrophilic dewetting patterns. 

Kaufman F et al. Chemical-mechanical polishing for fabricating patterned W metal features as chip interconnects. J Electrochem Soc 1991 138 (11) 3460- 3465. 

Erosion can be qualitatively understood as a result of a pad held up by ILD surrounded by dished metal features. If the ILD covers a broad area, as it... 

In this paper, we report the evolution and quantification of the step-height-reduction-ratio, and subsequently extract the planarization distance for copper CMP for the first time. Conventional profilometry and the InSiteSOO photo-acoustic measurement tool were employed to quantify copper film thickness and topography. The Insite 300 operates upon the transient gradient technique and allows for noncontact, nondestructive metal film thickness measurement [5]. The utility of this metal thickness tool bypasses a number of issues which arise with conventional profilometry. The ability to accurately delineate metal feature edge positions and circumvent stress-induced curvature present in long profilometry scans is of principle importance. 

Figure 3 shows trapezoidal metallic features embedded in the regions of porous AI2O3 (Fig. 3a), which are obtained after localized anodization, and metallic pillars, which are obtained after chemical etching of porous AI2O3 (Fig. 3b). Being qualitative, Figs. 2 and 3 provide a framework for the analysis of the technological issues associated with localized anodization of A1 films.

Figure 3. Cross-sectional micrographs (a) microstructures with alternative regions of A1 and porous AI2O3 obtained after localized porous-type anodization, (b) trapezoidal metallic features obtained after chemical etching of porous AI2O3. Two while arrows show the depth of microgrooves (D) and undercut (U).

This section will review selected applications and devices produced by using localized porous-type anodization and, optionally, selective etching of either porous AI2O3 or Al. The fabrication of these devices shares the common technological issues and challenges discussed in Sect. Ill the choice of a reliable mask material, the fidelity of the mask transfer, the trapezoidal profile of metallic features, the... 

EMM can be applied to either Al films, typically deposited on SiCVSi substrates, or Al foils. The dimensions of metallic features are determined by the same rules the etch factor, the depth of porous-type anodization, the mask design, and process conditions. In addition to the fabrication of metallic microstructures, EMM can be used to produce microstructured ceramic substrates composed of porous AI2O3. For the fabrication of both types of 3D microstructures by localized porous-type anodization, the following technological problems have to be addressed the reliability of a mask material, the fidelity of the mask transfer, volumetric expansion of porous AI2O3 during anodization, and the effect of the mask design on the rate of porous-type anodization and on the completion of anodization of the entire thickness of Al without traces of Al islands. 

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