Physics Research Proposals
Group B (Grade 11)

Getting to know Semiconductors.

An investigation into the peculiar electrical properties of semiconductors.

Special properties of semiconductors make possible modern devices such as computers and cell phones. In this project some of these properties that distinguish semiconductors like silicon and germanium from metals are investigated.

• How electrical conductivity depends on temperature will form the first part where, after establishing the conductivity of copper for different temperatures, the strange behavior of germanium will be looked at and compared to that of copper.
• After explaining the difference in conductivity, the second and main part of the project can begin where the simplest semiconductor device namely the diode will be studied.
  To get familiar with the instruments involved a commercial diode will be tested for any preference in the direction it can conduct current.
  A diode will then be manufactured by thermal evaporation of gold on silicon and tested and compared to the commercial one. Basic electronic circuits will be constructed to understand the function and applications of diodes.

Participants

• Pierre de Villiers