In nano-scale systems, design for manufacturability is essentially required. For sub 20 nm technology node, Self-Aligned Double Patterning (SADP) is an important manufacturing technique, and complex two-dimensional patterns are requested to be fabricated by SADP. However all two-dimensional patterns cannot be fabricated by SADP. In this paper, two-dimensional patterns that satisfy connection requirements as well as manufacturability by SADP are effectively derived by our proposed approach in which partially pre-colored two-color base grid is used.

Although self-aligned double and quadruple patterning (SADP, SAQP) have promising processes for sub-20 nm node advanced technologies and beyond, not all layouts are compatible with them. In advanced technologies, feasible wafer image should be generated effectively by utilizing SADP and SAQP where a wafer image is determined by a selected mandrel pattern. However, predicting a mandrel pattern is not easy since it is different from the wafer image (or target pattern). In this paper, we propose new routing methods for spacer-is-dielectric (SID)-type SADP, SID-type SAQP, and spacer-is-metal (SIM)-type SADP to generate a feasible layout satisfying the connection requirements. Routing algorithms comprising simple connecting and cutting rules are performed on a new grid structure where two (SID-type SADP) or three colors (SID-type SAQP and SIM-type SADP) are assigned alternately to grid-nodes. Then a mandrel pattern is selected without complex coloring or decomposition methods. Also, we try to reduce hotspots (potentially defective regions) by the proposed dummy pattern flipping for SID-type SADP. In experiments, feasible layouts meeting the connection requirements are generated and the effectiveness of the proposed framework is confirmed.

In this paper, we propose a multicast protocol, called BAM: branch aggregation multicast, for wireless sensor networks. The main contribution of BAM is a reduction in the radio communication load, which is a dominant factor of sensor energy consumption. BAM does not use any control packet such as join/leave messages and does not manage multicast groups. BAM is highly compatible with existing wireless sensor protocols, such as routing protocols, MAC protocols, and other kinds of energy efficient protocols. BAM implementation is quite simple and BAM works on various networks even if some sensors are not BAM-capable. BAM is composed of two aggregation techniques. One is single hop aggregation (S-BAM) and the other is multiple paths aggregation (M-BAM). S-BAM aggregates radio transmission within single hop and enables just single transmission to multiple intended receivers. M-BAM aggregates multiple paths into fewer ones and limits the range of radio transmission. S-BAM is designed to reduce redundant communication at every branch and M-BAM is designed to reduce the number of branches. SM-BAM, the combination of S-BAM and M-BAM, can reduce the radio communication load thus enabling energy efficient multicast communication. We evaluated BAM in three ways, qualitative evaluation by theoretical analysis, quantitative evaluation through computer simulations, and experiments using CrossBow's MICA2. Our results show that BAM is a very energy efficient multicast protocol that well supports wireless sensor networks.

The current mobile IP specification forces all packets forwarded to a mobile terminal (MT) to be routed via that terminal's home agent (HA), which often leads to triangular routing, which in turn causes data transmission delay and wastes network resources. IETF (Internet Engineering Task Force) is studying a solution that can optimize the route length, but this solution requires the implementation of additional functions on all correspondent nodes, so it will not be realistic. The paper proposes the use of mobile IP border gateways (MBGs) to optimize the routing in a carrier-scale network and reduce the processing burden on the HA without adding more functions to the correspondent nodes, and shows the effect of reducing the route length and the HA's load. We also propose a hierarchical arrangement of foreign agents (FAs) to reduce the processing burden on MBGs.