 # Semi-Conductor Questions Flashcards Preview

## ELEC104P > Semi-Conductor Questions > Flashcards

Flashcards in Semi-Conductor Questions Deck (27):
1

## How do you estimate the concentration of electrons and holes in a p-type semiconductor?

### np refers to the concentration of electrons 2

## How do you calculate the concentration of electrons and holes in an n-type semiconductor?

### pn refers to hole concentration 3

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## What is the Hall coefficient ? 5

## What equation would you use to calculate the built-in voltage of a silicon PN junction? 6

## The equation that relates the depletion region width (lengths) to the concentration? What does it tell us?

### Tells us that depletion regions can only be symmetric if the donor and acceptor concentration are equal.xn region of the donor , n for negative xp  region of the accepto, p for positive 7

8

## Graphical representation of the effect a reverse and forward bias has on the diffusion current. 9

## The equation for Itotal through a pn junction ? What is this equation essentially?

### The equation for current through a diode. 10

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## What is the equation for current density? 13

14

## The equation for the energy of a photon? 15

## If you have the band gap energy, what equation do you use to determine the wavelength? 16

## The equation for current through solar cell ? 17

## Sketch the IV characteristic of a solar cell in the dark and under light.Include all details. Where is the region of interest for extracting solar power?

### Include Iphoto and V oc  and the region for extracting power 18

## What is the equation for the short circuit current for a solar cell ? 19

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## The equation for the oxide capacitance of a MOSFET?

### Where epsilon is the numerator and tox thickness of oxide layer 22

## The equation for overdrive voltage? 23

## State which of the materials given in Table 7.1 would be suitable for use in an LED, and why. ### LEDs work when the PN junction is in the forward bias. LEDs are based on electron-hole recombination. The electromagnetic energy they release is equal to the band gap energy. 24

## For each number, name the region and suggest a specific material (including dopants) from which it can be made.  25

## The equation to calculate the concentration of electrons in the conduction band. 26

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