Which material class used in electronics has conductivity that increases with temperature?

Which material class used in electronics has conductivity that increases with temperature?

• A. Conductor
• B. Semiconductor
• C. Insulator
• D. Alloy

Answer: (B)

Temperature affects how many charge carriers are available to move in a material. In metals, more heat means more lattice vibrations that scatter electrons, so conductivity tends to drop as temperature rises. In semiconductors, however, higher temperature supplies enough energy to generate more electron-hole pairs, increasing the number of charge carriers and thus increasing conductivity. This intrinsic rise in carrier concentration with temperature is the defining behavior of semiconductors in electronics. Insulators stay poor conductors, and alloys don’t have this same characteristic trend as a rule. So, the material class whose conductivity increases with temperature is semiconductors.

Temperature affects how many charge carriers are available to move in a material. In metals, more heat means more lattice vibrations that scatter electrons, so conductivity tends to drop as temperature rises. In semiconductors, however, higher temperature supplies enough energy to generate more electron-hole pairs, increasing the number of charge carriers and thus increasing conductivity. This intrinsic rise in carrier concentration with temperature is the defining behavior of semiconductors in electronics. Insulators stay poor conductors, and alloys don’t have this same characteristic trend as a rule. So, the material class whose conductivity increases with temperature is semiconductors.