The leakage current in the transistor (Ge)

Explanation:

• As the temperature of a transistor increases, the collector current will increase because:
• Intrinsic semiconductor current between the collector and base increases with temperature.
• Its flow through the biasing resistors drives the base more positive, increasing forward bias on the base-emitter diode.
• For a silicon diode Simpson quotes an increase of 2 nA for a 10°C temperature rise.
• The base-emitter voltage required for a given collector current will decrease. This decrease is about −2.5mV/°C.

NOTE:

• Reverse saturation current (IS) of the diode increases with an increase in the temperature the rise is 7%/ºC for both germanium and silicon and approximately doubles for every 10ºC rise in temperature.