Consider a P-body MOS capacitor with following parameters: doping in the body region Na1015 cm-3, thickness...
A MOS capacitor is made on n-type silicon with oxide thickness of 50 A, a positive interface charge of 5 x 1010 cm2 and a uniform positive oxide charge of density p- 2 x 106 cm3 throughout the oxide. The substrate is doped with Na-101" cm3 and the gate is polysilicon doped with boron just to the edge of degeneracy (p+ poly, Ef -Ev). a. Calculate the flat band voltage VB and the threshold voltage Vr b. Sketch the charge...
Problem3: Consider a MOS capacitor maintained at T 300K with the following characteristics: Assume Esi 1.9,x 3.9,8.85 x 10-14 F/cm, and n 1.5 x 1010cm3 . Gate material is n+ poly-silicon . Total negative oxide charge of 5x 1011q C/cnm2 . Substrate is n-type Si, with doping concentration 1x1016 cm3 Oxide thickness 5 nm . The electron affinity for Si is 4.03eV? a) Draw the band diagram at equilibrium. b) From part (a). What is the substrate (bulk) condition at...
from Semiconductors class 2. An n-MOSFET has substrate doping N,-10°cm, oxide thickness ox-50 nm and n+ poly silicon gate. The oxide has fixed charge of 2 x1010/cm2 Cim 1. Calculate the flat band voltage VF Hint: fixed charge adjustsVby OIC 2. Threshold voltage V HINT
Problem 3: Consider a MOS capacitor maintained at T= 300K with the following characteristics: Assume s 11.9, ox 3.9, 8.85x 10-1 F/cm, and n 1.5 x 1010cm3 Gate material is n poly-silicon Total negative oxide charge of 5x 1011q C/cm . Substrate is n-type Si, with doping concentration 1 x1016 cm-3 Oxide thickness 5 nmm The electron affinity for Si is 4.03eV? e) What is the flat capacitance? f) What is the depletion region width? g) What is the potential...
Problem 5: The gate capacitance vs. gate voltage characteristic of a p+ poly-Si gated MOS capacitor of area 1x10"cm', is as shown: Assume Esi = 11.9, Eox-39,E,-8.85 × 10-14 F/on, and nl = 1.5 x 1010 cm3 Co [Farads] 3.45x1011 >Va [Volts] 1.0 0.3 (a) Is the semiconductor (silicon) substrate doped n-type or p-type? Explain briefly. (b) Is the measurement frequency low or high? Explain briefly. (c) What is the thickness of the gate oxide (SiO2), xo? (d) Estimate the...
Problem 6: The energy band diagram for an ideal MOS-capacitor is shown below. tx 0.2 μm and Ep = E, at the Si-SiO2 interface. Assume no oxide charge and φ'm5-0. Answer the following. EpM Eps Toz9ev 055ev a) What is the numerical value of the electron concentration at the Si-SiO2 interface? b) What is the substrate doping type and concentration? c) What is the electrostatic potential at the Si-SiO2 interface? d) What would be the depletion depth (width)? e) What...
Q1 Which of the following is true for a MOS capacitor with a P-type body? Select one: a. The charge in the inversion layer stays approximately constant as the gate voltage is increased above the threshold voltage b. The charge in the depletion region is proportional to the square root of the depletion region width, assuming that the body is uniformly doped c. In inversion, the total charge is equal to the sum of the charge in the depletion region...
Problem 3 (25 points) Consider a MOS capacitor with p polysilicon gate and p-type silicon substrate with NA 1016 cm3. Ef- Ev in the polysilicon gate. Assume the following parameters: I200A, , 1.5x10° cm*,E, -3.9x8.854x104FIcm ox a) (5 points) Calculate the metal-semiconductor work function difference. b) (5 points) Calculate the surface potential at the threshold inversion. c) (5 points) Calculate the depletion width (in μm) at the threshold inversion. d) (5 points) Calculate the flat band voltage. e) (5 points)...
An n-channel Sí MOSFET (ni-1.5 1010 cm-3 ,er-11.8) with 50 nm thick HfO2 high- K dielectric (Er-25). The device width is W-10 m wide. The distance between the source and drain is L 0.5 μm long. The diffusion constant of the minority carriers in the channel at room temperature is 25 cm2/s. The n+ poly-Si gate is doped with Np 1020 cm-3 donors. This MOSFET is designed to have a threshold voltage of Vt 0.5 V. A gate-source voltage of...
Problem 1: The MOSFET as a Resistor Consider an n -poly-Si-gated long-channel n-MOSFET with WIL- 10, effective gate- oxide thickness Toxe 2 nm, and substrate (body) dopant concentration NA- 1018 cm3: (a) Calculate the gate-to-source voltage VGs required for the MOSFET to present a resistance of 1 kΩ between the source and drain at low values of VDS. (Hint: You will need to solve this problem iteratively when you consider the dependence of effective mobility leff on the effective vertical...