Consider an n-channel Silicon MOS system with a substrate resistivity of 10 0-cm and with a...
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...
6. A MOS system has an n+ polysilicon gate and a p-type silicon substrate doped to N. =10cm. Assume there is an oxide surface charge density (Q,/q) = 100cm 2. Design the oxide thickness so that V1 = 0.5 V (no bias is applied between the channel and substrate). Answer: x 58.5 nm OX
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)...
In the silicon-based n-channel MOSMET. the work function of gate electrode 4a 4.08eV and the electron affinity of silicon χ = 4.05eV. The fixed oxide charge located at Si-SiO2 interface has a density of 5x1014 m-2 . The silicon substrate is doped with boron atoms in a concentration of 2x10*°m3. The oxide layer has a thickness of 200nm. Calculate (i) the flat band voltage, (ii) the threshold voltage to induce the inversion layer and ii) the maximum, minimum and flat...
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: 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...
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...
1. MOSFET is made on silicon substrate doped with boron to a concentration of 5x1027 cm. Silicon oxide layer of thickness 5 nm is used as an insulator. Gate electrode is made of n-type polysilicon doped to a concentration of 8x1018 cm Width and length of the transistor are 10 micrometer and 100 nm respectively. For this transistor find: a) saturation drain voltage at gate voltage 7 V; b) transconductance at gate voltage 6 V. 160 mev 140
3. A MOSFET is made on silicon substrate doped with boron with a concentration of 1018 cm. Width and length of channel are 100 and 0.1 micron respectively. Thickness of the oxide insulator under the gate is 10 nm. Find transconductance of this transistor and saturation current at gate voltage 6 V. kT (Nc Si eNa2egp Cox 3. A MOSFET is made on silicon substrate doped with boron with a concentration of 1018 cm. Width and length of channel are...
Problem 1. An n-channel MOS transistor is fabricated with the following specifications: Substrate is a p-type silicon with doping concentration NA=2x1015 cm-3 . The SiO2 gate thickness is 200 Å. Effective interface charges Qi=6.5x10-9 col/cm2. Work function difference between gate conductor and silicon substrate qфms=-0.95 eV. Calculate the following: a. Maximum depletion width, with respect to ground b. Gate capacitance per unit area, Ci c. Flat-band voltage, VFB d. Threshold voltage, VT.