Bias Stress Induced Conduction Mechanism Evolution in Silica Based Inter-Metal Dielectrics
The real-time conduction mechanism evolution during bias stress of three silica based inter-metal dielectrics in Cu damascene structures was investigated. Capacitance measurements at 1 MHz and I-V measurements were intermittently inserted into the process of bias stress to monitor the conduction mechanism evolution with time. All experiments show that the capacitance is constant and the I-V curve slope decreases with bias stress and converges to the half of the initial value. Based on these findings, we conclude that the conduction mechanism changes from a normal Frenkel-Poole emission to an "abnormal" Frenkel-Poole emission with bias stress
Enhanced dielectric-constant reliability of low-k porous organosilicate glass (k = 2.3) for 45-nm-generation Cu interconnects
The mechanism of the dielectric-constant increase in porous organosilicate glasses (OSGs) under electric-field stress has been revealed for the first time, where the dielectric-constant increase is caused by the oxidation of methyl groups in porous OSGs. By optimizing the methyl content, the authors developed a highly reliable, novel low-k porous OSG (k =2.3) with a dielectric-constant lifetime of 10/sup 3/ years for 45-nm-generation copper interconnects. The newly developed porous OSG was successfully integrated into 240-nm-pitch copper interconnects, where the line-to-line capacitance shows a much longer lifetime than the case of conventional porous OSGs.
Exploring interculturally competent teaching in social sciences classrooms
Abstract This paper explores a grounded research-based framework for intercultural competence and discusses the implications of interculturally competent teaching in the classroom and beyond. Given the importance of teachers being interculturally competent in today’s diverse classrooms, a number of questions, based on the framework, are presented, which guide teachers in reflecting upon their own teaching practice and the ways in which they integrate aspects of intercultural competence into their classrooms. The paper also provides some examples from the USA of ways in which intercultural competence development is being addressed in teacher training.