We study the level spacing distribution p(s) in the spectrum of random networks. According to our numerical results, the shape of p(s) in the Erdős-Rényi (E-R) random graph is determined by the average degree k and p(s) undergoes a dramatic change when k is varied around the critical point of the percolation transition, k = 1. When k 1, the p(s) is described by the statistics of the Gaussian orthogonal ensemble (GOE), one of the major statistical ensembles in Random Matrix Theory, whereas at k = 1 it follows the Poisson level spacing distribution. Closely above the critical point, p(s) can be described in terms of an intermediate distribution between Poisson and the GOE, the Brodydistribution. Furthermore, below the critical point p(s) can be given with the help of the regularized Gamma-function. Motivated by these results, we analyse the behaviour of p(s) in real networks such as the internet, a word association network and a protein-protein interaction network as well. When the giant component of these networks is destroyed in a node deletion process simulating the networks subjected to intentional attack, their level spacing distribution undergoes a similar transition to that of the E-R graph.

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We investigated the Al post metallization annealing (PMA) effect on Al2O3/GeOX/Ge gate stacks. The Al-PMA is effective for Al2O3/GeOX/Ge gate stacks, similar to the case of SiO2/GeO2 gate stack. It was found that interface states density in the lower half of the band gap and slow trap density can be reduced by Al-PMA at 400°C. However, a serious problem occurred in the metal source/drain (S/D) MOSFET fabricated using the gate stack with Al-PMA, which was poor electrical isolation between gate and S/D. It was found that Al-PMA at 400°C caused the reaction of Al with Al2O3 film on the S/D side wall, resulting in a decrease in insulating quality of Al2O3 film. To solve this problem, we demonstrated a method for depositing a thin SiO2 film on the S/D side wall.

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