Relationship between Cornea and Lid Margin Position on the Appearance of Strabismus.

PURPOSE: Previous strabismus appearance studies using images from real face photographs could not preclude the effect of other facial landmarks, such as position and contour of brow, nose, and facial outline, from pure effect of ocular deviation itself. With conceptualized drawings of eyes, we simulated strabismus deviation and collected the responses of observers. METHODS: The experiments consisted of three sessions: (1) one-eye, (2) two-eye cornea, and (3) two-eyelid deviation simulations. On a monitor, eight different ocular deviations in increments of 6 prism diopters of horizontal or vertical deviations were simulated. Nine ophthalmology residents were asked to choose between esotropia and exotropia for horizontal simulations and hypotropia or hypertropia for vertical simulations. Psychometric function fitting was performed. Detection sensitivity, point of subjective equality, and 95% thresholds were calculated. RESULTS: Between cornea and lid deviation simulations, there was no difference in 95% thresholds, points of subjective equality, and sensitivity (all p values > 0.10), reflecting that the relative location of cornea and lid was the determinant factor in recognizing ocular deviation. The sensitivities of vertical deviation simulations were higher than that of horizontal in two-eye cornea and lid comparisons (p values < 0.04) but not in one-eye (p value = 0.37). CONCLUSIONS: Our results suggest that the appearance of strabismus depends not on the absolute ocular alignment but rather on the reciprocal relationship of cornea and lid margin. Vertical misalignment was more apparent than horizontal misalignment.

Vacuum Inner Spacer to Improve Annealing Effect during Electro-Thermal Annealing of Nanosheet FETs.

Electro-thermal annealing (ETA) in a MOSFET utilizes Joule heating. The high-temperature heat effectively cures gate dielectric damages induced by electrical stresses or ionizing radiation. However, even though ETA can be used to improve the reliability of logic and memory devices, applying ETA in state-of-the-art field-effect transistors (FETs) such as nanosheet FETs (NS FETs) has not yet been demonstrated. This paper addresses the heat distribution characteristic of an NS FET considering the application of ETA, using 3D simulations. A vacuum inner spacer is newly proposed to improve annealing effects during ETA. In addition, evaluations of the device scaling and annealing effect were performed with respect to gate length, nanosheet-to-nanosheet vertical space, and inner spacer thickness. Guidelines for ETA in NS FETs can be provided on the basis of the results.

Impact of Iterative Deuterium Annealing in Long-Channel MOSFET Performance.

In contrast to conventional forming gas annealing (FGA), high-pressure deuterium annealing (HPD) shows a superior passivation of dangling bonds on the Si/SiO2 interface. However, research detailing the process optimization for HPD has been modest. In this context, this paper demonstrates the iterative impact of HPD for the better fabrication of semiconductor devices. Long-channel gate-enclosed FETs are fabricated as a test vehicle. After each cycle of the annealing, device parameters are extracted and compared depending on the number of the HPD. Based on the results, an HPD condition that maximizes on-state current (ION) but minimizes off-state current (IOFF) can be provided.