Transcript Department of Electron Devices Preparation for the first mid

Budapest University of Technology and Economics
Department of Electron Devices
Preparation for the first midterm test
16 October 2008, in the
class (V2 323)
http://www.eet.bme.hu
Budapest University of Technology and Economics
Department of Electron Devices
Conditions of the test
Time alloacted to the test is 60min. 20 minitues will be
allowed to answer 6 short questions. This part of the test
will be collected after time elapsed. The answers to the
short questions must be given on separate sheets of
paper. The answer must be a word, half sentence, a
formula or diagram – such that the evaluation of the
answer could be straightforward.
Passing the test (satisfactory mark – 2):
24 points out of the maximum of 48 points.
08-09-2008
Microelectronics BSc course, Requirements © András Poppe & Vladimír Székely, BME-EET 2008
2
Budapest University of Technology and Economics
Department of Electron Devices
Example for the test
Short questions (2 points/question)
1. What is the formula of the drift current for electrons?
2. What is the formula of the I-V characteristic of an ideal diode?
3. If we increase the reverse voltage of a pn junction, how does the
space charge capacitance change?
etc.
Total of 12 points
08-09-2008
Microelectronics BSc course, Requirements © András Poppe & Vladimír Székely, BME-EET 2008
3
Budapest University of Technology and Economics
Department of Electron Devices
Example for the test
Essay question (24 points)
Describe the static conditions of the PN junction!
Problem solving (6+6 points = 12 points)
In an abrupt Si PN junction the doping concentrations are as
follows: Na = 1017/cm3, Nd = 1014/cm3.
What is the value of the UD built-in potential of the junction? In
case of a reverse voltage of 5V what will be the width of the
depletion layer?
08-09-2008
Microelectronics BSc course, Requirements © András Poppe & Vladimír Székely, BME-EET 2008
4