No abstract

Plasma damage of low-k dielectrics during photoresist (PR) stripping in a dual-damascene process is a critical issue in the application of copper/low-k technology for ⩽45nm nodes to increase the signal processing speed of integrated circuit devices. In this article, a detailed and systematic work has been conducted to study the low-k damage on porous methyl silsesquioxane ultralow-k films using various PR strip chemistries and process conditions on a high density plasma reactor. The experimental results obtained from different test methodologies show that the low-k damage generated under fixed process conditions increases in the order of NH3<N2<H2∕N2<H2<O2. Among plasma control parameters, bias power has a very pronounced effect on low-k damage for reducing chemistries due to the acceleration of Si–C bond breaking by ion bombardment. Source power also affects the low-k damage significantly as it controls the ion density and flux to the wafer surface. The pressure effect is more complicated and shows different characteristics for oxidizing and reducing chemistries. The extent of low-k damage depends on the orientation of the wafer surface exposed to the plasma, leading to different sensitivity of the damage to the strip chemistry and process condition. Based on this work, an optimized chemistry and process regime are identified to effectively reduce low-k damage and achieve good strip process performance.

Abstract-A technology for multicasting packetized multimedia streams such as IPTV over the Internet backbone is proposed and explored through extensive simulations. An RSVP or DiffServ algorithm is used to reserve resources (i.e., bandwidth and buffer space) in each packet-switched IP router in an IP multicast tree. Each IP router uses an Input-Queued (IQ) switch architecture with unity speedup. A recently proposed low-jitter scheduling algorithm is used to pre-compute a deterministic transmission schedule for each IP router. The IPTV traffic will be delivered through the multicast tree in a deterministic manner, with bounds on the maximum delay and jitter of each packet (or cell). A playback buffer is used at each destination to filter out residual network jitter and deliver a very low-jitter video stream to each end-user. Detailed simulations of an IPTV distribution network, multicasting 75 high-definition video streams over a fully-saturated IP backbone are presented. The simulations represent the transmission of 129 billion cells of real video data and where performed on a 160-node cluster computing system. In the steady-state, each IP router buffers approx. 2 cells (128 bytes) of video data per multicast output-port. The observed delay jitter is zero when a playback buffer of 15 milliseconds is used. All simulation parameters are presented.

No abstract

Telerobotic control systems can tolerate a fixed delay in the control loop, but are highly sensitive to delay jitter. Before such systems can be widely deployed over the Internet, packet switching techniques which ensure a high 'Quality of Service' (QoS) and low delay jitter will be required. It is shown that guaranteed-rate traffic flows can be delivered over the Internet backbone with very low delay jitter, provided that each IP router (and the destination playback buffer) have the capacity to buffer a small number of switch cells per flow. An RSVP or DiffServ algorithm must be used to reserve guaranteed bandwidth and buffer space in the IP routers. Each IP router must schedule the guaranteed rate traffic for transmission according to a recently proposed QoS switch scheduling algorithm, which exploits a Recursive Fair Stochastic Matrix Decomposition algorithm. Computer simulations illustrate that very low delay jitters can be achieved.I.