What fraction of the surface centers will be filled

Assignment Help Physics

Reference no: EM131505097

Question 1: The energy band diagram for a reverse-biased Si pa-junction diode under steady-state conditions is pictured in Fig

(a) With the aid of the diagram and assuming single-level R-G center statistics, T_n = T_p = T, and E_T' = E_i, simplify the general steady-state net recombination rate expression to obtain the simplest possible relationship for R at (i) x = 0, (ii) x = - x_pp, (iii) x = x_nn (iv) x = -x_p and (v) x = x_n.

(b) Sketch It versus x for x-values lying within the electrostatic depletion region (-x_p ≤ x ≤x_n).

Question 2: The energy band diagram for a forward-biased Si pn-junction diode maintained under steady-state conditions at room temperature (T = 300 K) is pictured in Fig. Note that E_Fn - E_j = E_i, E_Fp = E_G/4.

(a) For the particular situation pictured in Fig. and assuming single-level R-G center statistics, τ_n = τ_p = τ, and E_T' = E_j, show that the steady-state net recombination rate inside the electrostatic depletion region (-x_p ≤ x ≤ x_n) can be simplified to

R ≅ n_i/T [e^E_G/4kT/c^{(F_N - E_i)kT} + e^{(Ei - Fp)/kT}]

(b) Plot R/(n_i/τ) versus x for -x_p ≤ x ≤ x_n' Assume the E_i variation between x = -x_p and x = x_n is approximately linear in constructing the plot.

Question 3: The surface of an n-bulk solar cell is subjected to intense illumination giving rise to high level injection (Δn_s = Δp_s >> nso). The surface region of the device is characterized by the energy band diagram shown in fig.

(a) What fraction of the surface centers at E = F_N, E = E_i, and E = F_P will be filled for the specified steady-state situation? (Let D_Filled be the number of filled surface centers per eV-cm² at E. the fraction of filled surface centers is then D_Filled/D_IT.) Sketch D_Filled/D_IT versus E for E_V ≤ E ≤ E_c. Assume c_ns = cps for all E in this part of the problem.

(b) Defining R_s = s*Δp_s, obtain an approximate closed-form expression for s* involving only ΔE = F_N - F_p and the parameters c_ns' cps, and D_IT evaluated at mid-gap. Invoke and record all reasonable assumptions and simplifications needed to complete this problem.

Reference no: EM131505097

Questions Cloud

Discuss ways in which the argument will have to be modified : The prisoners' dilemma game offers insights into the incentives to cheat of agents who will not be placed in the same situation again, such as two criminals.

Recommend two new feature of windows server active directory : Recommend two new features of Windows Server 2012 Active Directory that you believe to be most beneficial to users from a network security standpoint.

Review the risk management plan project requirements : Review the Risk Management Plan Project requirements included below to be sure that your rough draft includes all necessary project components.

Normal or acceptable in another society or culture : Why do you think something might be considered deviant in one society but totally normal or acceptable in another society or culture?

What fraction of the surface centers will be filled : What fraction of the surface centers at E = FN, E = Ei, and E = FP will be filled for the specified steady-state situation

Opportunity to interview a female-identified : During Modules 2 and 3, you will have the opportunity to interview a female-identified and a male-identified individual regarding their perceptions.

Differentiate cournot behaviour and the cournot equilibrium : ‘The common characteristic of the Cournot model is that it assumes a common pattern of reaction by competitors in each period which, despite the fact.

Individual or the sociological impact of the group : What is more important in determining terrorists' motives: the psychology of the individual or the sociological impact of the group?

What are your plans after you have successfully completed : What are your plans after you've successfully completed this class? Have you looked into the ICND 1 Certification exam yet?

User Account

All Pages