a) Determine and TABULATE all material parameters used including doping. mobility, and lifetime.
2. A Si crystal that is 2cm³ in size has been n-type doped uniformly at a ratio of 1 in 105. The intrinsic concentration of silicon is 1 x 10¹0 cm³ and its atomic concentration is 5 x 1022 cm³. Figure 1 shows how the drift mobility varies with dopant concentration at room temperature (300K). a) What is the donor concentration? b) What is the hole concentration? c) Using the graph in Figure 1 and your answers to a) and b), calculate the electrical resistance of the n-type doped silicon crystal. d) We now dope the silicon crystal with boron atoms instead of arsenic to create a p-type semiconductor. We again doped the crystal uniformly at a ratio of 1 in 10 What is the electrical resistance now? Compare your result to that obtained in c), giving a reason for any difference.
b) Graph the semilog I-V results from calculation obtained in part a). MATLAB only.
4) Consider table 2.5 (pp165). Calculate the Heat flow in a tungston rod 1 m long with a radius of 0.1 m, where one end is at 200C and the other end is at 25C. Provide your answer in watts.
Start with the equations for density of states as a function of energy and the Fermi function and derive the equation for the effective density of states. This question has two parts: (i) setting up the initial integral properly, and (ii) performing the steps to derive the equation for effective density of states.
Start with the Fermi function: (i) Plot it at 0 K, 100 K, 300 K, 900 K, and 2700 K (ii) Assume we are using Si with the density of states in the conduction band and valence band as we wrote down in class (reference the slides for the equation). Make 1 plot with the electron concentration on the left y axis, the hole concentration on the right y axis, and the Fermi level as the x axis. Calculate this using the full equation for electrons and holes, not the effective density of states approximation you just derived. Make another plot of the same data, but the Y axis should be log scale, not linear scale.
JFET Project JFET DESIGN Study Sec. 4.5 (textbook). Design an n-channel Silicon JFET with a Pinch off voltage of -20 V with following constraints: Gate width = 0.1 cm Use only Phosphorous or Born dopants Physical design parameters must be reasonable and feasible for JFET fabrication Hand Calculations: a) Must tabulate all parameters obtained, the device geometry as well as any other unknown parameters such as the channel thickness, channel length, doping densities, carriers mobility, built-in potential, and turn off voltage (VI). b) Calculate substrate's resistance used. c) Calculate Ipat and Voat for VG at 0 V, -5 V, -10 V, -15 V, must tabulate. ORCAD: d) Submit Library file for JFET e) Examine (hand-calculated) Vr from part (a) f) Examine results in part (c) show both hand calculations and ORCAD on graph
Consider the circuit on Figure 1, in which D1 is a 10 Volts Zener diode and R₁ = 1 ΚΩ. 1. Clearly specify (draw) the polarity of diode D1. (6 pts.)