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Owing to tunability of MTJ stack characteristics based on perpendicular magnetic anisotropy control via sophisticated magnetic material engineering, STT-MRAM can meet a wide range of product specifications for various applications: 1) flash-type applications such as microcontroller and AI inferencing device and 2) SRAM-type applications such as frame buffer memory. However each application has different reliability challenges. In this paper, we discuss the reliability requirements for Flash-type and SRAM-type STT-MRAM, verifying superb reliability of highly tunable STT-MRAM technology.

We demonstrate a novel way of integrating STT-MRAM for on-chip hybrid memory which exhibits either features of high-retention or high-speed implemented in separate zones in a single chip. For satisfying high-temperature retention requirement, tailored MTJs are shown to support > 10 year retention at 220°C. For high-speed operation, critical improvements have been made in terms of TMR, short fail probability, overdrive and write error rate. The new integration provides a manufacturable way of combining diverse memory components by modulating non-volatility of STT-MRAM without affecting within-chip distributions of critical properties.

A compact and unique design of the integrated quench protection (QP) system for the high-current superconducting magnet coils has been fabricated and tested for the toroidal field (TF) coil system of the Korea Superconducting Tokamak Advanced Research (KSTAR) device. The QP system is capable of protecting the TF superconducting magnet coils, which consist of 16 identical coils serially connected with a stored energy of 495 MJ at the design operation level, 35.2 kA per turn.

We propose a polarization interferometry technique to measure the electro-optic coefficient in an optically active system. The technique makes use of the interference of two polarization states of the incident beam after experiencing both the electro-optic phase modulation and the optical rotation in the Bi/sub 12/SO/sub 20/ crystal.

Summary form only given. In plasma source ion implantaion (PSII), the target is biased by successive negative voltage pulses with an intrinsic finite rise time to implant ions from plasma to target surface, resulting in a time-dependent sheath around target. In this work, the Langmuir probe was used to study the sheath motion around a planar target with various pulse conditions and plasma conditions in PSII. It was observed that the time-dependent sheath consisted of two parts: the ion matrix sheath development and the dynamic sheath motion. A new model for the ion matrix sheath development was proposed to explain the experimental results which showed discrepancies compared with Lieberman's model (Stewart and Lieberman, 1991) and the computer simulation. The ion matrix sheath development was in proportion to square root of pulse rise rate over plasma density and also to square root of pulse rise time. The dynamic sheaths were faster than the ion acoustic speed after the pulse rise and eventually slowed down to approximately a third of ion acoustic speed.

To establish the design guide on coupling between inductor pairs, we measured the magnitude of the electromagnetic coupling between inductors with the variation of physical separation and substrate resistivity. We also found that the coupling effect degrades the reverse isolation of L-band CMOS LNAs, and analyzed several LNAs fabricated with different fabrication technology. Furthermore, we proposed inductors for preventing the coupling, and its coupling reduction effect on the LNA is demonstrated.