A novel cylinder-type metal-insulator-metal (MIM) capacitor in porous low-k film (CAPL) is proposed for embedded DRAMs (eDRAMs). The CAPL removes long bypass-contacts (BCT) with high resistance, which have been used to connect transistors with Cu interconnects by way of the MIM capacitor layer. A key technical challenge for the CAPL integration is control of pore structure in the low-k film to avoid metal contamination during the gas-phase deposition of the MIM electrode (BE) on the porous low-k film. A molecular-pore-stack (MPS) SiOCH film (k=2.5) with very small pores (0.4 nm-diameter) is found to be the best candidate for the CAPL structure, applicable to eDRAM with high performance logics for 28 nm-node and beyond. IntroductionEmbedded DRAM with a conventional COB (capacitor over bit-line) in SiO 2 pre-metal-dielectric (PMD) is attractive to keep high bandwidth, low latency, and low power of the memory-logic interface with small cell size [1-2]. The conventional COB structure, as shown in Fig. 1, is a straightforward solution to insert add-on process for MIM capacitors into the CMOS technology. In this structure, long W-contacts, what we call bypass contact (BCT), are needed to connect the transistors with Cu Metal-1 (Fig. 1). Scaling of the CMOS technology shrinks the diameter of the W-BCT and increases the aspect ratio of W-contact. These changes bring significant increases in parasitic resistance and capacitance of the long W-BCT (Fig. 2), and degrading circuit performances of CMOS logics with the eDRAM, compared to those of pure CMOS logics.To suppress those parasitic effects, a structural paradigm shift is needed in scaled-down eDRAM device,

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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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