An n-channel MOS transistor is made on a p-type substrate with Na = 1015 cm-3. Find approximate depletion charge per unit area (Qd) at strong inversion.\(\left\{ {ln\;\left( {10} \right) = 2.3,\;\;\sqrt {0.046} \approx 0.215,\;\;{n_i} = {{10}^{10}}c{m^{ - 3}}} \right\}\)

An n-channel MOS transistor is made on a p-type substrate with Na = 10

1.	An n-channel MOS transistor is made on a p-type substrate with Na = 1015 cm-3. Find approximate depletion charge per unit area (Qd) at strong inversion.\(\left\{ {ln\;\left( {10} \right) = 2.3,\;\;\sqrt {0.046} \approx 0.215,\;\;{n_i} = {{10}^{10}}c{m^{ - 3}}} \right\}\)
A.	-6.9 × 10-8 C/cm2
B.	6.9 × 10-8 C/cm2
C.	-3.4 × 10-8 C/cm2
D.	3.4 × 10-8 C/cm2
Answer» D. 3.4 × 10-8 C/cm2