1,720,961 research outputs found
Forming Gas Anneal effect on plasma-induced damage: beyond the appearances
No full textIndispensable for manufacturing of modern CMOS technologies, plasma processes result in charging of dielectric surfaces, thus damaging the gate oxide. A forming gas annealing (FGA) step is usually done at the end of the process to passivate and/or recover this damage. We investigated this problem on thin (3.5 nm) gate oxides by using a series of stress-anneal-stress steps on devices with different level of latent damage. Our results confirm that FGA actually reduces the number of traps responsible for stress-induced leakage current (SILC) or for microbreakdown in ultrathin gate oxides, but also put in evidence that defects induced by plasma treatments and those generated by way of electrical stress feature different anneal kinetics. Further, we have identified two categories of dielectric breakdown events, whose characteristics are strongly modified by the FGA step
Plasma-induced Micro Breakdown in small area MOSFETs
No full textPlasma treatments, indispensable for manufacturing of ULSI integrated circuits, may lead to a latent damage in gate oxides of CMOS components. Latent damage may endanger the device long-term reliability, which is usually tested over large area MOS devices. In this work, we investigated the impact of latent plasma induced damage on the reliability of nMOSFETs with small gate area and gate oxide thickness of 3.2 nm. To this purpose, we stressed 1,500 devices with different antenna areas by using a staircase-like stress voltage, and by monitoring the gate leakage at the gate voltage VG=2V. The stress was always stopped because of an abrupt jump in the gate current. The statistics obtained for the breakdown current is characterized by two different oxide breakdown modes. The first is the well-known HardBreakdown, while the second one, which we called Micro Breakdown, can be modeled as a Double Trap Assisted Tunneling mechanism, and is characterized by a very small leakage current (around 100pA at the gate voltage VG=2V). In devices with large antenna, i.e., more prone to be damaged by plasma processing, the number of micro broken oxides is larger and breakdown occurs at lower voltages than in reference devices (non plasma damaged). For converse, the Hard Breakdown statistics shows only a weak dependence on the gate antenna ratio of plasma damaged devices. This has been explained by considering the intrinsic nature of latent plasma-induced oxide defects, linkedto the different generation mechanisms involved in Micro Breakdown and Hard Breakdown phenomena
Depassivation of Latent Plasma Damage in n-MOSFETs
No full textIndispensable in CMOS manufacturing, plasma treatments may result in a latent damage in gate oxides. We propose a method to detect this latent damage as a function of the area of the multifingered metal pad connected to the gate, by using an experimental method based on constant current stress and oxide trapped charge measurements. We measured a power law behavior describing the dependence of the trapped charge on the injected charge
Correlation Between Soft Breakdown and Plasma Process Induced Damage
No full textThe correlations between soft breakdown (SB) and plasma process induced damage of devices with ultra-thin gate oxides were presented. A stress and test methodology was proposed to analyze SB due to sudden decrease in gate voltage during a constant current stress. The voltage used for measurements was kept small to avoid Fowler-Nordheim tunneling. The analysis suggested the dependence of cummulative failure distribution on antenna ratio. It was found that the use of low voltages caused more localized damage and increased the chance trigger SB spot into conduction
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Radiation induced depassivation of latent plasma damage
No full textThe radiation impact on antenna devices can give new insights on basic mechanisms underlying the latent plasma damage nature and radiation hardness of commercial CMOS technologies for space applications. When MOS structures are exposed to ionizing radiation, electron-hole (e/sup -/-h/sup +/) pairs are created along the track of the incident particle. Some fraction of these e/sup -/-h/sup +/ pairs will recombine, and that fraction is a function of the oxide material, the kind of radiation, and the applied oxide electric field. In general, thinner oxides are less prone to radiation effects than thicker ones; applied bias permits to investigate (modulate) the trap creation in the bulk oxide and at the interface. In this study X-rays and e-beam sources have been considered. Although an e-beam LINAC with 8 MeV electrons is a standard source for radiation hardness characterization, its use is difficult for irradiating wafer with a large diameter. On the other side, fully automated protestations with X-ray tubes are commercially available. As a fair comparison, for a given dose and SiO/sub 2/ oxide technology, X-rays usually have a larger detrimental impact on MOSFET I-V characteristics with respect to the e-beam. Electrical stresses reactivate the latent plasma damage as well as ionizing radiation, but fewer studies have addressed the latter aspect and most of them date back to the older MOS technologies of the 70's and 80's. More recently, plasma damage reactivation in a 17.5- nm oxide due to ionizing, radiation has been addressed. The rapid evolution of plasma equipments and MOS technologies, such as the reduction of the gate oxide thickness well below 10 nm and the increase of the metal levels, suggests extending this investigation to more recent CMOS generations. This has been the purpose of this work, which is concentrated on the latent damage reactivation induced by ionizing radiation on a commercial 0.35 /spl mu/m (t/sub ox/=7 nm) CMOS technology
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Plasma induced damage from via etching in pMOSFETs
No full textIn this paper, we present a study of micro breakdown (MB), soft breakdown (SB), and conventional hard breakdown (HB) on pMOSFET devices. In particular, we report evident damage due to via etching
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