{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

ECE216-Lecture-17-Metal-Gate-MOS-Capacitors

ECE216-Lecture-17-Metal-Gate-MOS-Capacitors - ECE 216...

Info iconThis preview shows pages 1–10. Sign up to view the full content.

View Full Document Right Arrow Icon
ECE 216 DEVICE PHYSICS FOR INTEGRATED CIRCUITS Lecture 17 METAL-GATE MOS CAPACITORS Professor Hisham Z. Massoud Department of Electrical and Computer Engineering Fitzpatrick Building, Room 3521 Duke University, Durham, NC 27708–0291 [email protected] https://courses.duke.edu/webapps/portal/frameset.jsp ECE 216 Chapter 10 – Metal-Gate MOS Capacitors Lecture 17.1
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
LECTURE 17 – TOPICS 10. Bias-Voltage Dependence of MOSCAP Variables 11. MOSCAP Small-Signal Capacitance-Voltage Characteristics ECE 216 Chapter 10 – Metal-Gate MOS Capacitors Lecture 17.2
Background image of page 2
10. BIAS-VOLTAGE DEPENDENCE OF MOSCAP VARIABLES The bias-voltage dependence of the MOSCAP variables can be obtained in the following way: 1. Start by selecting a value of V SC,B that corresponds to conditions of strong accumulation in the substrate. In a metal-gate MOSCAP fabricated on a p -type substrate, a starting value of V SC,B of - 1 . 0 V is a good choice. 2. Calculate Q SC,B using the Q SC,B ( V SC,B ) relationship. 3. Calculate E x,B (0 + , V GB ) from Q SC,B . 4. Calculate E x,OX (0 - , V GB ) from E x,B (0 + , V GB ), Q f , and Q it ( V GB ). 5. Calculate V OX ( V GB ) from E x,OX (0 - , V GB ), Q mi , and Q ot . 6. Calculate Q G ( V GB ) from the charge-conservation relationship. 7. Calculate V GB from the potential-distribution relationship. 8. Calculate ψ B ( x, V GB ) for the chosen value of V SC,B by numerical in- tegration. ECE 216 Chapter 10 – Metal-Gate MOS Capacitors Lecture 17.3
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
10. BIAS-VOLTAGE DEPENDENCE OF MOSCAP VARIABLES 9. Calculate n B ( x, V GB ) from ψ B ( x, V GB ). 10. Calculate p B ( x, V GB ) from ψ B ( x, V GB ). 11. Calculate % B ( x, V GB ) from n B ( x, V GB ) and p B ( x, V GB ). 12. Calculate E x,B ( x, V GB ) from ψ B ( x, V GB ). 13. Change V SC,B to a new value V SC,B + δV SC,B where δV SC,B is a small increment. 14. Repeat steps 2 to 12. 15. Plot the variable of choice vs V GB . ECE 216 Chapter 10 – Metal-Gate MOS Capacitors Lecture 17.4
Background image of page 4
10. BIAS-VOLTAGE DEPENDENCE OF MOSCAP VARIABLES Q mi + Q ot Q f + Q it Q G E x,OX Q SC,B V SC,B V OX V GB ϕ PM ECE 216 Chapter 10 – Metal-Gate MOS Capacitors Lecture 17.5
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
10. BIAS-VOLTAGE DEPENDENCE OF MOSCAP VARIABLES Gate-to-Bulk Voltage, V GB (V) Substrate Space-Charge Voltage, V SC,B (V) p -Si, 300 K, X ox = 20 nm N - a,B =4 . 0 × 10 15 cm - 3 ϕ PM = 0 V, Q f = Q it = 0 E v /q E i /q E c /q - 2 - 1 0 1 2 3 4 - 0.4 - 0.2 0 0.2 0.4 0.6 0.8 1.0 1.2 ECE 216 Chapter 10 – Metal-Gate MOS Capacitors Lecture 17.6
Background image of page 6
10. BIAS-VOLTAGE DEPENDENCE OF MOSCAP VARIABLES Gate-to-Bulk Voltage, V GB (V) Substrate Space-Charge Density, | Q SC,B | ( μ C/cm 2 ) Flat-band Depletion Strong Inversion Accumulation p -Si, 300 K, Q f = Q it = 0, ϕ PM = 0 N a,B = 4 . 0 × 10 15 cm - 3 , X ox = 20 nm - 5 - 4 - 3 - 2 - 1 0 1 2 3 4 5 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 ECE 216 Chapter 10 – Metal-Gate MOS Capacitors Lecture 17.7
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
10. BIAS-VOLTAGE DEPENDENCE OF MOSCAP VARIABLES Gate-to-Bulk Voltage, V GB (V) Substrate Space-Charge Density, | Q SC,B | (C/cm 2 ) Flat-band Depletion Accumulation Strong Inversion p -Si, 300 K, Q f = Q it = 0, ϕ PM = 0 N a,B = 4 . 0 × 10 15 cm - 3 , X ox = 20 nm - 5 - 4 - 3 - 2 - 1 0 1 2 3 4 5 10 - 9 10 - 8 10 - 7 10 - 6 10 - 5 10 - 4 ECE 216 Chapter 10 – Metal-Gate MOS Capacitors Lecture 17.8
Background image of page 8
10. BIAS-VOLTAGE DEPENDENCE OF MOSCAP VARIABLES Gate-to-Bulk Voltage, V GB (V) Oxide Electric Field, |E x,OX ( V GB ) | (MV/cm) Flat-band
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 10
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}