9.10. FURTHER READING 487
Na=5× 1016 cm−^3 at 300 K. The other parameters for the device are the following:
Vfb = − 0 .5V
μn = 600 cm^2 V−^1 s−^1
μp = 200 cm^2 V−^1 s−^1
Gate length = 1. 5 μm
Gate width = 50. 0 μm
dox = 500A ̊
The inversion condition isVs=2φF. Assume that the electrons induced under inversion
areinaregion200A wide near the Si/SiO ̊ 2 interface.
(a) Calculate the channel conductivity near the Si-SiO 2 interface under flat band condition
and at inversion. Use the conditionVs=2φFfor inversion.
(b) Calculate the threshold voltage.
Problem 9.4Consider ann-MOSFET at room temperature made from Si-dopedp-type.
To characterize the device C-V measurements are done for the MOS capacitor. It is found
from the low-frequency measurements that the maximum and minimum capacitances per
unit area are 1. 72 × 10 −^7 F/cm^2 and 2. 9 × 10 −^8 F/cm^2. The other parameters for the
device are the following:
μn = 600 cm^2 V−^1 s−^1
Gate length = 1. 5 μm
Gate width = 50. 0 μm
(a) Calculate the oxide thickness.
(b)Estimate thep-doping level in the channel.
(c) Calculate the channel current at saturation when the gate bias isVT+1. 5 V.
9.10FURTHERREADING ...............................
- General
- E. H. Nicollian and J. R. Brews,MOSPhysicsandTechnology (Wiley, New York,
1982).
- D. A. Neamen,SemiconductorPhysicsandDevices:BasicPrinciples (Irwin, Boston,
MA, 1997).
- R. F. Pierret,FieldEffectDevices (Vol. 4 of the Modular Series on Solid State
Devices, Addison-Wesley, Reading, MA, 1990).
