2 a silicon pn junction has impurity doping

This preview shows page 1. Sign up to view the full content.

This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: nge 200 < T < 400 K. The built- in potential is given by (7.10) as 31 ⎛N N ⎞ ⎛ T ⎞ ⎡ 2 ⋅ 4 ⋅ 10 ⎤ Vbi = kBT ln ⎜ a 2 d ⎟ = 0.0259 ⎜ ln ⎢ ⎝ 300 ⎟ ⎣ (1.8 × 10 6 )2 ⎥ ⎠ ⎝ ni ⎠ ⎦ ⎛T⎞ = 1.157 ⎜ ⎝ 300 ⎟ ⎠ This is shown in the figure below: 2 1.5 Built-In Potential (V) 7.7 1/2 ⎧ 2ε sVbi ⎫ ⎧ 2 ⋅ 11.7 ⋅ 8.854 × 10 −12 ⋅ 0.731 ⎫ Na xn = ⎨ ⎬ =⎨ ⎬ −19 22 ⎩ 1.6 × 10 ⋅ 2 ⋅ 2 × 10 ⎭ ⎩ e Nd (Na + Nd ) ⎭ −6 = 0.154 × 10 m = 0.154 µ m 1 0.5 0 200 250 300 350 400 Temperature (K) 8.2 A silicon pn junction has impurity doping concentrations of Nd = 2 x 1015 cm- 3 and Na = 8 x 1015 cm- 3. Determine the minority carrier concentrations at the edges of the space charge region for (a) Va = 0.45 V, (b) Va = 0.55 V, and (c) Va = - 0.55...
View Full Document

{[ snackBarMessage ]}

Ask a homework question - tutors are online