Mehrban Jam

Roll-to-roll manufacturing of electronics on flexible substrates using self-aligned imprint lithography (SAIL)

Abstract— The manufacture of large-area arrays of thin-film transistors on polymer substrates using roll-to-roll (R2R) processes exclusively is being developed. Self-aligned imprint lithography (SAIL) enables the patterning and alignment of submicron-sized features on meter-scaled flexible substrates in the R2R environment. SAIL solves the problem of precision interlayer registry on a moving web by encoding all the geometry information required for the entire patterning steps into a monolithic three-dimensional imprint with discrete thickness modulation. The pre-aligned multiple-step mask structure maintains its alignment regardless of subsequent substrate distortion. Challenges are encountered in relation to the novel nature of using flexible substrates and building toolsets for the R2R processing. In this paper, methods of the SAIL process, the resulting active-matrix backplanes, the trajectory of SAIL process development, and the remaining issues for production are presented.

Advances in roll-to-roll imprint lithography for display applications

A solution to the problems of roll-to-roll lithography on flexible substrates is presented. We have developed a roll-toroll imprint lithography technique to fabricate active matrix transistor backplanes on flexible webs of polyimide that have a blanket material stack of metals, dielectrics, and semiconductors. Imprint lithography produces a multi-level 3- dimensional mask that is then successively etched to pattern the underlying layers into the desired structures. This process, Self-Aligned Imprint Lithography (SAIL), solves the layer-to-layer alignment problem because all masking levels are created with one imprint step. The processes and equipment required for complete roll-to-roll SAIL fabrication will be described. Emphasis will be placed on the advances in the roll-to-roll imprint process which have enabled us to produce working transistor arrays.

Real time asset tracking in the data center

The importance and difficultly of asset tracking make it worthy of attention. We focus on data centers consisting of vertical racks where each rack may accommodate a variety of equipment. We describe an asset tracking system which automatically detects and identifies equipment within rack; has “pinpoint” accuracy, i.e., location resolution equals asset size; relays this information to possibly several management back-ends; includes a back-end application that maintains a location history for all equipment; and uses a visualization tool to display both the current state and the history of deployment.The solution features a flexible architecture that simplifies the connection with both existing and future asset management applications. The architecture supports simple configuration, load balancing, and redundancy. Care has been taken to use widely recognized standards wherever possible.

77.3: Invited Paper: Roll‐to‐Roll Manufacturing of Backplanes for Paper‐Like Displays

HP and Phicot are planning the worlds first R2R (roll-to-roll) manufacturing line for display backplanes based on the SAIL (Self-Aligned Imprint Lithography) process. Economic benefits for R2R compared to batch, cost comparisons of different R2R processes, comparison of substrate options, and necessary supply chain infrastructure developments are presented.

A Self-Configuring Sensing System for Data Centers

Wiring sensors in a data center is extremely expensive in comparison to the wiring of computing equipment. This is due to the central architecture of traditional sensing systems, which requires long wires to be connected between racks and a central box. In addition, a re-layout of the racks after the sensor wires are deployed is practically impossible. We propose using a wireless self-configuring network of smart sensing nodes to alleviate these problems. We explore how to design the sensor control software to be self-reconfiguring when nodes relocate. The software is divided in three layers: network organization, data aggregation and visualization. In this paper, we identify several insights into the thermal monitoring requirements, design issues and initial design solutions for these layers.

Defect analysis of roll-to-roll SAIL manufactured flexible display backplanes

HP and Phicot have made the worlds first roll-to-roll (R2R) manufactured active matrix displays. Currently we are developing a wrist-worn solar powered display for the U.S. Army. As we scale from research to preproduction on our 1/3 meter wide pilot line defect analysis and mitigation is our primary focus. In this presentation we will review the self-aligned imprint lithography (SAIL) process and discuss defects we observe, and the tools, and processes we have developed to detect and eliminate them

29.1: Invited Paper: Electrical Testing of Roll-to-Roll SAIL Manufactured Flexible Display Backplanes

HP and Phicot are making a fully roll-to roll fabricated display for a solar powered wrist display. We have developed methods for electrical testing of display backplanes on flexible substrates which are not bonded to a carrier. This has enabled improvement of yield through rapid electrical test feedback.