P-190L:Late-News Poster: Device Mobility >300 cm²/V·S Using Planarized Single-Crystal Silicon Spheres for Large Area Display Backplanes

Abstract

We report device mobility >300 cm 2 /V•s in a scalable process suitable for electronic backplanes for large area OLED displays. Single crystal Si spheres ~800 μm are planarized to form device substrates. Performance of transistors on spheres andCzochralski (CZ) silicon wafers are compared.

25‐1: Invited Paper: Progress in Active Pixel Technology for LED Video Walls

“…These substrates offer a high performance to cost ratio. For p-type spheres, bulk hole mobility of 400 cm 2 /Vꞏs has been achieved [1], electron mobility for field effect transistors on a Si wafer using a scalable process of > 500 cm 2 /Vꞏs has been realized [2] and device mobility of > 300 cm 2 /Vꞏs has been measured on planarized SCS spheres [3].…”

“…Larger sheets are readily cast in the green phase. The LTCC and device processes have been described previously [1][2][3]. The conformal coating uses a glass overglaze or encapsulant that allows planarization and polishing as the alumina ceramic is quite hard and typical polishing compounds use alumina particles as the abrasive.…”

“…As the active area of the substrate is a small fraction of the total are of the substrate, tiling is straightforward and can be achieved using the same alignment techniques being used for passive LED walls. Figure 4 shows typical output characteristics, transfer characteristics, and transconductance (Gm) curve for transistors with a channel length of 5µm fabricated on a sphere surface [3].…”

69‐4: Active Backplane Design for Digital Video Walls

“…These substrates offer a high performance to cost ratio. For p-type spheres, bulk hole mobility of 400 cm 2 /V·s has been achieved [1], electron mobility for field effect transistors on a Si wafer using a scalable process of > 500 cm 2 /V·s has been realized [2] and device mobility of > 300 cm 2 /V·s has been measured on planarized SCS spheres [3].…”

“…The LTCC and device processes have been described previously [1][2][3]. The conformal coating uses a glass overglaze or encapsulant that allows planarization and polishing as the alumina ceramic is quite hard and typical polishing compounds use alumina particles as the abrasive.…”