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Con este trabajo lo que se pretende es contestar a la pregunta de si realmente es necesario tener un/una instructor/a que nos haga un seguimiento durante las clases simplemente dirigiendo y motivando o si el/la instructor/a debe hacer uso de un aparato tecnológico objetivo que ayude a controlar de mejor manera a sus participantes.

The traditional Cu interconnect barrier/seed process consisting of PVD-Ta based barrier/Cu-seed will reach its limit between 20 nm and 30 nm wide trench dimension. To extend Cu interconnect technology further, possible solutions such as PVD-RuTa, PEALD-Ru-based, CVD-Co, PVD/CVD-self-formed-MnSixOy and self-assembled monolayers (SAMs) are studied. It is shown that both PVD-RuTa and CVD-Co possess the so-called seed enhancement capability allowing Cu filling of narrow recesses. However, they exhibit limitations in terms of Cu-diffusion barrier efficiency, electromigration reliability and scalability. Despite, the concept of SAM [NH2-SAM(C3)] as Cu diffusion barrier is demonstrated, it requires maturity and compatibility within the process flow (e.g. adhesion with the Cu overlayer). Finally, it is considered that PEALD-Ru-based alloys and CVD-based MnSixOy films are serious candidates for sub-30 nm wide trench technologies because of their conformal nature and ability to act as an efficient Cu diffusion barrier in the range of 2 nm thickness.

A 3-aminopropyltrimethoxysilane-derived self-assembled monolayer (NH 2 SAM) is investigated as a barrier against copper diffusion for application in back-end-of-line (BEOL) technology. The essential characteristics studied include thermal stability to BEOL processing, inhibition of copper diffusion, and adhesion to both the underlying SiO 2 dielectric substrate and the Cu over-layer. Time-of flight secondary ion mass spectrometry and X-ray spectroscopy (XPS) analysis reveal that the copper over-layer closes at 1-2-nm thickness, comparable with the 1.3-nm closure of state-of-the-art Ta/TaN Cu diffusion barriers. That the NH 2 SAM remains intact upon Cu deposition and subsequent annealing is unambiguously revealed by energy-filtered transmission electron microscopy supported by XPS. The SAM forms a well-defined carbon-rich interface with the Cu over-layer and electron energy loss spectroscopy shows no evidence of Cu penetration into the SAM. Interestingly, the adhesion of the Cu/NH 2 SAM/SiO 2 system increases with annealing temperature up to 7.2 J m -2 at 400°C, comparable to Ta/TaN (7.5 J m -2 at room temperature). The corresponding fracture analysis shows that when failure does occur it is located at the Cu/SAM interface. Overall, these results demonstrate that NH 2 SAM is a suitable candidate for subnanometer-scale diffusion barrier application in a selective coating for copper advanced interconnects.

The RC delay and power restrictions imposed by the interconnect system can contribute to poor circuit performance in an increasingly severe manner as dimensions shrink. Resistances are increasing faster than the scale factor of the technology and capacitance improvements are constrained by mechanical requirements of the assembled stack. Collectively, these cause a bottleneck in both local and global information transfer on a chip. Novel deposition methods and novel conductor materials are being explored as means to increase conductive cross sectional area. Molecular ordering is an opportunity to simultaneously deliver capacitance and mechanical strength. Despite these improvement paths, a more holistic approach to interconnect design is needed, where the application and micro architecture are more tolerant of RC scaling constraints.

This work presents the first fabricated and characterized MEMS in polycrystalline silicon-germanium (poly-SiGe) for biosensing applications. The devices, clamped-clamped microresonators, combine the possibility of above-IC MEMS-CMOS integration with a stiction-free design that enables biomolecule mass sensing in air. By perforating the resonant beam with square or hexagonal holes, a higher surface-to-volume ratio is achieved leading to an increased relative frequency shift for a certain analyte surface density. A minimum detectable mass of ∼2pg in air was calculated. A mass sensing test was performed on these perforated devices by immobilization of biotin and the extraction of the resulting resonance frequency shift.

Two different material-selective Self assembled monolayers (SAMs) were successfully deposited on Cu and SiO 2 structures that mimic the Dual Damascene integration scheme. A two-step SAM coating process is presented. First, a “sacrificial” SAM is deposited at the Cu bottom and secondly, a “barrier” SAM at the SiO 2 surface. The order in the SAMs deposition sequence and the differential thermal release of the thiol “sacrificial” SAM vs. the amino “barrier” SAM, allows an oxide-free Cu-to-Cu connection at the vias bottom. While the sacrificial SAM is selectively released by thermal ablation, the barrier SAM remains intact on the dielectric sidewall and field regions, ready for the subsequent copper metallization.

The effects of suspension and functionalisation on electrical conduction of silicon nanowires (SiNWs) are experimentally investigated towards highly sensitive chemical and biological detection applications. The conductance is found to be affected by the suspension process, while it shows the similar trend against the temperature before and after the suspension. The reduction of conductance after the functionalisation with NH"2 self-assembled monolayer/glutaraldehyde/biotin can be explained based on the assumption that there is a charge transfer from the SiNW to the molecular layers. The temperature insensitive conductance found in the functionalised SiNWs experimentally for the first time is expected to be extremely useful for practical sensing applications.

This paper investigates a selective self-assembly process for formation of a self-assembled monolayers (SAM) barrier to Cu diffusion in dual damascene integration. In selecting a barrier, trichlorosilanes are promising due to their high thermal stability (above 550degC) and dense molecular packing. Overall, this study demonstrates that the tuneable structure and chemistry of SAMs provides a molecular level engineering approach for future device structures.

RESUMEN: Se construyó un cuestionario para evaluar creencias centrales asociadas con los trastornos de la personalidad, fundamentadas en el Modelo de la Terapia Cognitiva. Se realizó el análisis estructural y la validez de contenido de la prueba en población universitaria de la ciudad de Medellín, Colombia. La muestra fue representativa y elegida al azar a través de un procedimiento polietápico. Un número de 809 estudiantes universitarios contestaron el cuestionario de creencias centrales de los trastornos de la personalidad (CCE-TP). Se realizó un análisis factorial exploratorio de la prueba, reagrupándose los ítems en 14 factores (F) que representan el 61,3% de la varianza. F1: CCE-TP antisocial (8 ítems, a 0,839); F2: CCE-TP esquizotípico/límite (8 ítems, a 0,846); F3: CCE-TP histriónico/patrón seductor (6 ítems, a 0,833); F4: CCE-TP paranoide (6 ítems, a 0,836); F5: CCE-TP por evitación / autopercepción negativa (5 ítems, a 0,755); F6: CCE-TP por dependencia (5 ítems, a 0,797); F7: CCE-TP histriónico/ dependencia emocional (4 ítems, a 0,755); F8: CCETP obsesivo-compulsivo/perfeccionista (4 ítems, a 0,808); F9: CCE-TP por evitación/hipersensible (4 ítems, a 0,766); F10: CCE-TP obsesivo-compulsivo/ crítico frente a los demás (3 ítems, a 0,851); F11: CCE-TP narcisista (4 ítems, a 0,717); F12: CCE-TP pasivo-agresivo / temor a ser dominado (3 ítems, a 0,719); F13: CCE-TP pasivo-agresivo/crítico frente a la autoridad (3 ítems, a 0,685), y F14: CCE-TP esquizoide (2 ítems, a 0,774). El alfa de Cronbach de la prueba fue de 0,931. ABSTRACT: A questionnaire was designed to assess beliefs associated with personality disorders, based on cognitive therapy model; its psychometric properties and structural validity were established in a university student population in the city of Medellín, Colombia. The sample was representative and randomly selected through a poliphasic procedure. The number of students taking the Central Beliefs Questionnaire of Personality Disorders (Cuestionario de Creencias Centrales de los Trastornos de la Personalidad CCE-TP) was 809. An exploratory factor analysis was carried out, items grouping in 14 factors (F), variance 61,3%. The factor with highest variance level was F1: CCE-TP antisocial (8 items, a 0,839), followed by F2: CCE-TP schizotypal/borderline disorders (8 items, a 0,846), F3: CCE-TP histrionic/seductive pattern (6 items, a 0,833), F4: CCE-TP paranoid (6 items, a 0,836), F5: CCE-TP avoidant/negative self-perception (5 items, a 0,755), F6: CCE-TP dependent, (5 items, a 0,797), F7: CCE-TP histrionic/emotional dependence (4 items, a 0,755), F8: CCE-TP obsessivecompulsive / perfectionistic (4 items, a 0,808), F9: CCE-TP avoidant/hyper-sensitive (4 items, a 0,766), F10: CCE-TP obsessive-compulsive/overly critical to others (3 items, a 0,851), F11: CCETP narcissistic (4 items, a 0,717), F12: CCE-TP passive-aggressive/fear to domination, (3 items, a 0,719), F13: CCE-TP passive-aggressive/critical to authority (3 items, a 0,685), F14: CCE-TP schizoid (2 items, a 0,774). The Cronbach’s Alpha index was 0,931.

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An alternative bottom-up Cu electroless deposition (ELD) method without other catalyst material activation is the focus of this paper. The process consists of reducing the Cu ions in a solution via standard reducing agents such as dimethylamine borane. The reaction pH and ionic strength values can be modulated to impart to the metallic Cu particle surface an opposite charge with respect to the deposition substrate functionalized by the 3-aminopropyltrimethoxysilane (APTS) self-assembled monolayer used as a diffusion barrier. At neutral pH, the negatively charged Cu particles are electrostatically attracted by the positively charged NH 2 groups, and they can form strong interfacial complexes if the required activation energy budget is supplied. A design of the experiment is carried out to optimize the critical deposition parameters such as temperature, time, Cu ion concentration, and pH. The formed ELD Cu nuclei positioned preferentially on the APTS layer, showing a wetting behavior that is accentuated upon anneal, leading to a decrease in surface roughness that corresponds to an increase in film closure. The observed debonding energy of the ELD Cu/APTS surface is ca. 2.2 J/m 2 before anneal, while it reaches ca. 4.5 and 8 J/m 2 after a 10 min anneal under forming gas at 300 and 450°C, respectively.