Assertion–Reason (semiconductor properties): Silicon is less sensitive to temperature changes than germanium. Reason: The cut-in (turn-on) voltage in silicon is less than that in germanium.

Introduction / Context:
Temperature sensitivity determines the stability of diodes and transistors. Silicon (Si) and germanium (Ge) differ in band gap and intrinsic carrier generation, producing different thermal behaviors and turn-on voltages.

Given Data / Assumptions:

• Typical room-temperature band gaps: Si ≈ 1.12 eV, Ge ≈ 0.66 eV.
• Typical diode cut-in voltages: Si ≈ 0.7 V, Ge ≈ 0.3 V (order of magnitude).
• Comparison is for standard, undamaged devices under similar conditions.

Concept / Approach:
The intrinsic carrier concentration n_i grows roughly as exp(−E_g/(2kT)). A larger E_g (silicon) yields much lower n_i and a smaller temperature coefficient of leakage and parameters. Hence Si is less temperature-sensitive than Ge — the assertion is true. The reason claims Si has a smaller cut-in voltage than Ge, which is false; Si's cut-in is larger.

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