Thermal effects in Ni/Au and Mo/Au gate metallization AlGaN/GaN HEMT's reliability

AlGaN/GaN high electron mobility transistors (HEMT) are key devices for the next generation of high-power, high-frequency and high-temperature electronics applications. Although significant progress has been recently achieved [1], stability and reliability are still some of the main issues under investigation, particularly at high temperatures [2-3]. Taking into account that the gate contact metallization is one of the weakest points in AlGaN/GaN HEMTs, the reliability of Ni, Mo, Pt and refractory metal gates is crucial [4-6]. This work has been focused on the thermal stress and reliability assessment of AlGaN/GaN HEMTs. After an unbiased storage at 350 o C for 2000 hours, devices with Ni/Au gates exhibited detrimental IDS-VDS degradation in pulsed mode. In contrast, devices with Mo/Au gates showed no degradation after similar storage conditions. Further capacitance-voltage characterization as a function of temperature and frequency revealed two distinct trap-related effects in both kinds of devices. At low frequency (< 1MHz), increased capacitance near the threshold voltage was present at high temperatures and more pronounced for the Ni/Au gate HEMT and as the frequency is lower. Such an anomalous “bump” has been previously related to H-related surface polar charges [7]. This anomalous behavior in the C-V characteristics was also observed in Mo/Au gate HEMTs after 1000 h at a calculated channel temperatures of around from 250 o C (T2) up to 320 ºC (T4), under a DC bias (VDS= 25 V, IDS= 420 mA/mm) (DC-life test). The devices showed a higher “bump” as the channel temperature is higher (Fig. 1). At 1 MHz, the higher C-V curve slope of the Ni/Au gated HEMTs indicated higher trap density than Mo/Au metallization (Fig. 2). These results highlight that temperature is an acceleration factor in the device degradation, in good agreement with [3]. Interface state density analysis is being performed in order to estimate the trap density and activation energy.

Op[us] egregiu[m] / beatissimi Bernardi amplecte[n]s [ser]mo[n]es ei[us] de t[em]p[or]e, [et] sup[er] o[mn]es fere toti[us] a[n]ni festiuitates ...

Huecos para iniciales con letras de aviso

Solennis ac perutilis Repetitio c. Raynutius. extra de testa. (vt poteque de testamentis, vltimis voluntatib[us] institutionib[us] substitutionib[us] [et] h[uius]mo[d]i iuriu[m] difficultatib[us] pertractet) Iuris vtriusq[ue] monarche ... / do. Guillelmi

Port. arquitectónicas a dos tintas

Cómo se vive y cómo se muere en Bilbao : reseña demográfica de la I. Villa : obra dedicada por su autor al Excmo. Ayuntamiento de Bilbao e impresa por cuenta de la Corporación... / por Gumersindo Gómez.

Digitalización Vitoria-Gasteiz Archivos y Bibliotecas Julio 1994 18-62

Libro primero d las epistolas familiares / del Reuerendissimo señor don Antonio de Gueuara ..., obispo de Mo[n]doñedo ...

Sign.: []2, A-N8, O6

Tres iglesias sajonas fortificadas en Transilvania, Rumanía: Hosman, Pelişor y Moşna

Saxon colonization in Transylvania occurred from 12th Century with the establishment of the populations with certain degree of freedom and autonomy. External threats over this territory obliged to the fortification of their churches, mainly between 15th and 16th Centuries with the advance of Turkish Empire. The fortification of the churches consists on the building of walls with gates and flanking towers, and also with the incorporation of several defensive elements over the apses. Most outstanding characteristics of this fortified system are the homogeneity in typology, construction and polyorcetic, without detracting of the singularity of each one of the more of 150 conserved churches. The article presents an actual state of the art. Also, it develops the main historical elements and it explains the architectonic typology and the constructive characteristics. At last, defensive elements are analyzed from the comparative and deep study through three proper examples: the churches of Hosman, Pelisor and Mosna. La colonización sajona de Transilvania se produjo a partir del siglo XII con el asentamiento de poblaciones con cierto grado de libertad y autonomía. Las amenazas externas sobre este territorio obligaron a la fortificación de sus iglesias, principalmente entre los siglos XV y XVI ante el avance del imperio turco. La fortificación de las iglesias consta de la construcción de murallas con puertas y torres de flanqueo, además de la incorporación de diversos elementos poliorcéticos sobre las cabeceras de las iglesias. Las características más relevantes de este sistema fortificado es la homogeneidad tipológica, constructiva y poliorcética sin menoscabo de la singularidad de cada una de las más de 150 iglesias conservadas. El artículo presenta un estado de la cuestión actualizado, además de desarrollar los elementos históricos más relevantes, explicar la tipología arquitectónica y las característica constructivas y analizar los elementos poliorcéticos desde el estudio comparado y profundo de tres ejemplos característicos: las iglesias de Hosman, Pelisor y Mosna.

Characterization of a Mo/Au thermometer for ATHENA

The first dark characterization of a thermometer fabricated with our Mo/Au bilayers to be used as a transition edge sensor is presented. High-quality, stress-free Mo layers, whose thickness is used to tune the critical temperature (TC ) down to 100 mK, are deposited by sputtering at room temperature (RT ) on Si3N4 bulk and membranes, and protected from degradation with a 15-nm sputtered Au layer. An extra layer of high-quality Au is deposited by ex situ e-beam to ensure low residual resistance. The thermometer is patterned on a membrane using standard photolithographic techniques and wet etching processes, and is contacted through Mo paths, displaying a sharp superconducting transition (α ≈ 600). Results show a good coupling between Mo and Au layers and excellent TC reproducibility, allowing to accurately correlate dM o and TC . Since dAu is bigger than ξM for all analyzed samples, bilayer residual resistance can be modified without affecting TC . Finally, first current to voltage measurements at different temperatures are measured and analyzed, obtaining the corresponding characterization parameters.

Furs de Môço

Copia digital: Biblioteca valenciana, 2010

Oracion, que en la festiuidad celebrada por el Cabildo de la Sta. Iglesia Metropolitana de Valencia el dia 11, de Deciembre de 1773, por la traslacion del Santis[si]mo Sacramento al nueuo templo de las Escuelas Pías

Sign.: [A]-C4, D3

Letras de la Sagrada Congregacion del Concilio de orden de N.SS.P. y ... Clemente XII, que amonestan à todos los Eclesiasticos à que hagan una vez en el año los Exercicios Espirituales : Carta pastoral del Il.mo ... Andres de Orbe y Larreategui, Arzobispo de Valencia ... en que ... exorta al cumplimiento de dichas Letras. Edicto en que ... se manda ... à los Predicadores la explicacion de la Doctrina Christiana en ... los Sermones

Los tres textos están fechados al final en 1732

Alegacion juridica por parte del Dr. Dn. Juan Bautista Company... Cura... de Chestealcampo... en la causa que sigue con Vicente Sanchiz, Christoval Delaro y diferentes vecinos cosecheros... [Texto impreso] : sobre pago y respectiuo modo... de satisfacer el Diez- mo.

Sign. : []1, A-K2

Cu(In,Ga)Se2 absorber thinning and the homo-interface model: Influence of Mo back contact and 3-stage process on device characteristics

Thinning the absorber layer is one of the possibilities envisaged to further decrease the production costs of Cu(In,Ga)Se2 (CIGSe) thin films solar cell technology. In the present study, the electronic transport in submicron CIGSe-based devices has been investigated and compared to that of standard devices. It is observed that when the absorber is around 0.5 μm-thick, tunnelling enhanced interface recombination dominates, which harms cells energy conversion efficiency. It is also shown that by varying either the properties of the Mo back contact or the characteristics of 3-stage growth processing, one can shift the dominating recombination mechanism from interface to space charge region and thereby improve the cells efficiency. Discussions on these experimental facts led to the conclusions that 3-stage process implies the formation of a CIGSe/CIGSe homo-interface, whose location as well as properties rule the device operation; its influence is enhanced in submicron CIGSe based solar cells.

RETRATO DEL EX.MO É ILL.MO S.OR D.N FRAI JOAQUIN COMPANY [Material gráfico] : Caballero Gran Cruz de la Rl. distinguida Orden de Carlos III Arzobispo antes de Zaragoza y después de Valencia

Resumen: Descripción: retrato de 3/4 en el interior de un óvalo. Viste indumentaria de arzobispo. En el ángulo izqdo., la mitra y báculo

Optical absorption and applications of the ABO4 (A=Ca, Pb and B= Mo, W) semiconductors

Ternary molybdates and tungstates ABO4 (A=Ca, Pb and B= Mo, W) are a group of materials that could be used for a variety of optoelectronic applications. We present a study of the optoelectronic properties based on first-principles using several orbitaldependent one-electron potentials applied to several orbital subspaces. The optical properties are split into chemical-species contributions in order to quantify the microscopic contributions. Furthermore, the effect of using several one-electron potentials and orbital subspaces is analyzed. From the results, the larger contribution to the optical absorption comes from the B-O transitions. The possible use as multi-gap solar cell absorbents is analyzed.

1.8 Chicago Defender article "STIFF FIGHT IS SEEN IN MO. U. JIM CROW SUIT"

The NAACP argued that the 14th Amendment left the court with no other alternative than to order the admission of Gaines to Missouri. Judge W. M. Dinwiddie set July 10, 1936, for the presentation of oral arguments. Lloyd Gaines and the NAACP were ready to do battle.