Question

Notify Me Bookmark

An nMOS device has a gate oxide thickness of 100 Å, electron mobility μn = 90 cm2 /(V.s), threshold voltage VT = 0.70 V, and dimensions W = 5 μm and L = 0.25 μm. a. Determine the gate capacitance C8 and the device transconductance βn. b. Determine the region of operation and the current IDS when VDS = 2 V and for the three cases of VGS = 0.5 V, 1.5 V, and 3.5 V.

An nMOS device has a gate oxide thickness of 100 Å, electron mobility μn = 90 cm2 /(V.s), threshold voltage VT = 0.70 V, and dimensions W = 5 μm and L = 0.25 μm. a. Determine the gate capacitance C8 and the device transconductance βn. b. Determine the region of operation and the current IDS when VDS = 2 V and for the three cases of VGS = 0.5 V, 1.5 V, and 3.5 V.

Image text
An nMOS device has a gate oxide thickness of 100 Å , electron mobility μ n = 90 c m 2 / ( V . s), threshold voltage V T = 0.70 V , and dimensions W = 5 μ m and L = 0.25 μ m . a. Determine the gate capacitance C 8 and the device transconductance β n . b. Determine the region of operation and the current I D S when V D S = 2 V and for the three cases of V G S = 0.5 V , 1.5 V , and 3.5 V .

Detailed Answer

0 0

Please enter your email here. You will get email when this question is answered by our tutor.

Doubtrix Logo

Problem is not yet solved!

Click on Notify me to get email when question is answered.

Join Doubtrix with 7-days free trial

  • Icon Correct & Verified Answers
  • Icon No AI-Generated Answers
  • Icon Video Solution for Difficult Questions
  • Icon Work With Experts to Reach at Correct Answers
Notify me Login Sign Up

Similar/Related Questions

Consider the circuit shown below with a Si n−MOSFET. Given: VDD = 7 V, VG = 2 V and RL = 1.1 KΩ. Consider the MOSFET is operating in the linear region under this biasing condition. If the voltage drop across the drain and source terminals, VDS = 0.4 V and the threshold voltage, VT = 0.5 V. Calculate - (a) The drain current (IDS) and the power dissipated in the MOSFET. (b) 'ON resistance' of the MOSFET. (c) 'Conduction parameter (Kn)' of the MOSFET. (d) Capacitance of the gate oxide (Cox) [in F/cm2]. (e) Thickness of the gate oxide layer (tox) and the transconductance (gm) of the MOSFET. (f) Calculate the sheet electron concentration (ns) in the channel at the source end. Given: Channel length, L = 0.8 μm, Gate Width, W = 20 μm, electron mobility in the channel, μn = 800 cm2/Vs, and dielectric constant of the oxide layer is 3.9.
Solution
1 0

A MOS capacitor has an n+ polysilicon gate with EF = EC+0.15 eV in the polysilicon, a 50 nm thick SiO2 gate dielectric with Qss = 0, and a p-type silicon substrate with Na = x.5×1016 /cm3, where x is the last digit of your student number. For silicon at room temperature ni = 1010 /cm3, Nv = 1.8×1019 /cm3, Nc = 3.2×1019 /cm3, and ϵSi = 11.7ϵ0. For SiO2 ϵSiO2 = 3.9ϵ0. a. Find the threshold voltage for this MOS capacitor. b. If the capacitor is made into a MOSFET with L = 2 μm, W = 200 μm, and a channel field effect mobility of 450 cm2/V⋅s, find ID for VGS − VT = 2 V and VDS = 1 V. c. Suppose it is desired to have a depletion mode MOSFET and that any gate oxide thickness is possible, but no other parameters can be changed. What is the most negative threshold voltage that is possible for the MOS capacitor with your substrate doping? d. Suppose it is desired to have a MOSFET with a threshold voltage of +0.5 V and again any gate oxide thickness is possible, but no other parameters can be changed. What oxide thickness will give VT = 0.5 V ? e. Suppose the source, drain, and body of the MOSFET are all grounded and the capacitance-voltage characteristics are measured. Sketch the high and low frequency capacitance-voltage characteristics and label significant features.
Solution
0 0

An n-channel MOSFET has the following parameters: μn = 450 cm2 V−1s−1, tox = 35 nm, Vth = 0.8 V, L = 2 μm, W = 30 μm (a) Calculate the unit-area gate capacitance Cox(εo = 8.85×10−14 F/cm and εox = 3.9 for SiO2) (b) Calculate the process transconductance parameter kn′ = μnCox (c) Calculate and plot ID versus VDS for 0 ≤ VDS ≤ 5 V and VGS = 0, 1, 2, 3, 4, and 5 V, respectively. Indicate on each curve the VDS( sat) point the corresponding ID (sat). . (d) Calculate and plot ID versus VGS for 0 ≤ VGS ≤ 5 V and VDS = 1.2 V. Indicate on the curve the transition points between the cutoff region, saturation region, and linear region. (e) Follow Example 3 in the PSPICE simulation tutorial and use PSPICE to simulate the ID−VDS and ID−VGS curves for the MOSFET above. Compare your simulation results with your calculation results in part (c) and (d). Note: In PSPICE, the statement for specifying a MOSFET is: Mname D G S B model_name L = value W = value .Model model_name NMOS(VTO = value KP = value ) where VTO is the threshold voltage Vth, and KP is the process transconductance parameter kn'.
Solution
0 0