A visual defect in dyslexics?

2017 ◽  
pp. 137-156
Author(s):  
J.F. Stein
Keyword(s):  
Visual Defect

Analysis of an Anomalous CMOS Transistor Exhibiting Drain to Source Leakage—Its Model and Cause

2014 ◽  
Author(s):  
Yuk L. Tsang ◽  
Alex VanVianen ◽  
Xiang D. Wang ◽  
N. David Theodore
Keyword(s):  
Threshold Voltage ◽  
Crystalline Silicon ◽  
Electrical Characterization ◽  
Visual Defect ◽  
Scanning Capacitance Microscopy ◽  
Device Model ◽  
Graphical Simulation ◽  
Cmos Transistor

Abstract In this paper, we report a device model that has successfully described the characteristics of an anomalous CMOS NFET and led to the identification of a non-visual defect. The model was based on detailed electrical characterization of a transistor exhibiting a threshold voltage (Vt) of about 120mv lower than normal and also exhibiting source to drain leakage. Using a simple graphical simulation, we predicted that the anomalous device was a transistor in parallel with a resistor. It was proposed that the resistor was due to a counter doping defect. This was confirmed using Scanning Capacitance Microscopy (SCM). The dopant defect was shown by TEM imaging to be caused by a crystalline silicon dislocation.

Analysis of an Anomalous Transistor Exhibiting Dual-Vt Characteristics and Its Cause in a 90nm Node CMOS Technology

2012 ◽  
Author(s):  
Yuk L. Tsang ◽  
Xiang D. Wang ◽  
Reyhan Ricklefs ◽  
Jason Goertz
Keyword(s):  
Threshold Voltage ◽  
Electrical Characterization ◽  
Cmos Technology ◽  
Short Channel ◽  
Visual Defect ◽  
Subthreshold Region ◽  
Short Channel Effect ◽  
Channel Effect ◽  
Transistor Model

Abstract In this paper, we report a transistor model that has successfully led to the identification of a non visual defect. This model was based on detailed electrical characterization of a MOS NFET exhibiting a threshold voltage (Vt) of just about 40mv lower than normal. This small Vt delta was based on standard graphical extrapolation method in the usual linear Id-Vg plots. We observed, using a semilog plot, two slopes in the Id-Vg curves with Vt delta magnified significantly in the subthreshold region. The two slopes were attributed to two transistors in parallel with different Vts. We further found that one of the parallel transistors had short channel effect due to a punch-through mechanism. It was proposed and ultimately confirmed the cause was due to a dopant defect using scanning capacitance microscopy (SCM) technique.

Statistical methods for visual defect metrology

1999 ◽  
Vol 21 (2) ◽  
pp. 182
Author(s):  
Sean P. Cunningham ◽  
Scott MacKinnon
Keyword(s):  
Statistical Methods ◽  
Visual Defect

Visual Defect Detection of Metal Screws using a Deep Convolutional Neural Network

2021 ◽  
Author(s):  
Daniel Sauter ◽  
Cem Atik ◽  
Christian Schenk ◽  
Ricardo Buettner ◽  
Hermann Baumgartl
Keyword(s):  
Neural Network ◽  
Convolutional Neural Network ◽  
Defect Detection ◽  
Deep Convolutional Neural Network ◽  
Visual Defect

Use of 22 nm Litho SEM non-visual defect data as a process quality indicator

2012 ◽  
Author(s):  
C. A. Boye ◽  
C. J. Penny ◽  
J. Connors ◽  
D. Boyles ◽  
C. Janicki ◽  
...  
Keyword(s):  
Quality Indicator ◽  
Process Quality ◽  
Visual Defect

scholarly journals An unusual chiasmal visual defect in a patient with neuromyelitis optica: case report

2007 ◽  
Vol 70 (1) ◽  
pp. 153-155 ◽  
Author(s):  
Roberta Martins da Silva Costa ◽  
Antonio Carlos Santos ◽  
Laudo Silva Costa
Keyword(s):  
Case Report ◽  
Neuromyelitis Optica ◽  
Visual Defect

scholarly journals Epiretinal Membrane Surgery in Daily Clinical Practice: Results of a Proposed Management Scheme

2019 ◽  
Vol 2019 ◽  
pp. 1-6
Author(s):  
Jesús Pareja ◽  
Alba Coronado ◽  
Inés Contreras
Keyword(s):  
Epiretinal Membrane ◽  
Visual Loss ◽  
Observation Group ◽  
Visual Defect ◽  
Management Guidelines ◽  
Postsurgical Complications ◽  
Corrected Visual Acuity ◽  
Management Scheme ◽  
Visual Status

Purpose. To report the results of the epiretinal membrane (ERM) management guidelines followed in our center. Methods. Patients with ERM seen between 2014 and 2015, with ≥2 years follow-up or who had undergone ERM surgery, were included. Corrected visual acuity (VA), lens status, and ERM configuration were recorded at each visit. Our guidelines for ERM are if VA is ≥20/30, observation is recommended unless there is moderate/intense metamorphopsia. Vitrectomy is recommended during follow-up if there is a drop >one line in VA with changes in ERM configuration. If VA at diagnosis is <20/30, vitrectomy is recommended. If visual loss is thought to be due to cataract, phacoemulsification is performed first and visual status reevaluated. Results. Ninety-nine eyes of 94 patients were included; 52 eyes underwent vitrectomy, and 47 eyes were monitored. From eyes with VA at diagnosis <20/30 (41 eyes), 8 eyes underwent isolated phacoemulsification: VA improved to ≥20/30. Vitrectomy was recommended but refused by 4 patients. The other 29 eyes underwent vitrectomy. Of the 58 eyes with VA at diagnosis ≥20/30, 5 underwent surgery due to metamorphopsia. Eighteen eyes underwent vitrectomy during follow-up. VA improved a mean of 0.13 logMAR (SD 0.30) after vitrectomy. There were no differences in mean VA improvement between eyes that underwent vitrectomy within six months of diagnosis (0.24, SD 0.32) and those that underwent surgery more than six months after diagnosis (mean 0.17, SD 0.17), p=0.106. Three eyes developed postsurgical complications with visual loss: persistent macular edema in one eye, two consecutive retinal detachments in one eye, and a central visual defect in another eye. At the end of follow-up, VA was similar in the observation group (0.14, SD 0.14) and in the vitrectomy group (0.16, SD 0.28), p=0.528. Conclusions. Our proposed guidelines lead to visual preservation in most patients while limiting surgery and its possible complications.

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