Question

Applied quantum mechanics

1. Calculate the carrier concentrations (p and n) for Si at 300k for the following doping concentrations:

2.

(a) ND = 1015/cm3

(b) NA = 1018/cm3

(c) ND = 5 x 1017/cm3

Calculate the majority and minority carriers for each side of an N+P junction if ND = 2 x 1017/cm3 for the n-side, and NA = 1014/cm3 for the p-side.

Assume the semiconductor is Si and the temperature is 300K.

3. Determine the energy of:

(a) a photon if each has momentum equal to 1.071 x 10-21kgm/s (b) an electron and the photon in (a).

4. A photon is emitted as a result of an electron transition from a higher energy level to a lower energy level. Indicate the type of a photon that is emitted if its energy is equal to (a) 2.49 eV and (b) 1.38 eV. (Hint: Solve for the wavelength and use table 2.1 in the course notes to determine the type of photon.)

1. Calculate the carrier concentrations (p and n) for Si at 300k for the following doping concentrations (a) ND 101/cm3 b) NA-101/cm3 (c) N 5 x 10"/cm3 2. Calculate the majority and minority carriers for each side of an N+P junction if ND 2 x 10/cm for the n-side, and NA-10/cm for the p-side. Assume the semiconductor is Si and the temperature is 300K. 3. Determine the energy of: (a) a photon if each has momentum equal to 1.071 x 102 kg.m/s (b) an electron and the photon in (a) 4. A photon is emitted as a result of an electron transition from a higher energy level to a lower energy level. Indicate the type of a photon that is emitted if its energy is equal to (a) 2.49 eV and (b)1.38 eV. (Hint: Solve for the wavelength and use table 2.1 in the course notes to determine the type of photon.)

Answer 1

Given that: calculate the carrier concentrations (p + n) for si at 300k (a) N_D = 10^15/cm^3 implies P_0 =^cm^-3 n_0 = n^2_i/p_0 = (1.8 times 10^6)^2/10^15 implies n_0 = 3.24 times 10^- 3 cm^- 3 (b) N_A = 10^18 cm^- 3 implies n + 0 = 10^18 cm^- 3 p_0 = n^2_i/n_0 = (1.8 times 10^6)^2/10^18 implies p_0 = 3.24 times 10^- 6 cm^- 3 (c) N_D = 5 times 10^17 cm^-3 implies p_0 = 5 times 10^17 cm^- 1 n_0 = n^2_i/p_0 = (1.8 times 10^6)^2/5 times 10^17 implies n_0 = 6.48 times 10^- 6 cm^- 3 calculate the majority and minority carries for each side of an N + P junction N_D = 2 times 10^17/ cm^3 rightarrow n - side N_A = 10^14/ cm^3 rightarrow p-side \r\n At 300k concentration of si = 1.5 times 10^10/ cm^3 n^2_i = (npo)N_A npo = concentration of electron in p-side