Silicon is preferred over germanium primarily due to its superior thermal stability and wider operating temperature range. Silicon semiconductors can withstand higher temperatures compared to germanium without significant degradation in performance. This characteristic is crucial for semiconductor devices used in various applications where reliability and longevity are essential, such as in integrated circuits (ICs), solar cells, and power electronics. Additionally, silicon has better mechanical strength and is less prone to mechanical stress-induced failure compared to germanium, making it more suitable for mass production and diverse semiconductor applications.
Silicon and germanium are primarily used as semiconductors due to their atomic structures, which make them suitable for controlling electrical conductivity. Both elements have a crystalline structure that allows them to conduct electricity under certain conditions, such as when doped with specific impurities to create p-type and n-type semiconductor materials. This property forms the basis of semiconductor devices like diodes, transistors, and integrated circuits, which are fundamental components in modern electronics. The ability to selectively control conductivity through doping makes silicon and germanium indispensable in semiconductor manufacturing.
Silicon is preferred over germanium in photodetectors and photovoltaic devices (PV) primarily due to its lower sensitivity to temperature variations and better response to infrared wavelengths. Silicon-based photodetectors and solar cells exhibit higher efficiency and stability over a wider temperature range compared to germanium. This advantage is critical for applications where consistent performance under varying environmental conditions is essential, such as in solar energy harvesting and optical communication systems. Furthermore, silicon is abundant, cost-effective, and compatible with existing semiconductor fabrication processes, making it more practical for large-scale production of photonic devices.
The main disadvantages of germanium compared to silicon include lower thermal stability, narrower operating temperature range, and higher cost of production. Germanium semiconductors are more susceptible to thermal runaway at elevated temperatures, limiting their application in high-power devices and environments requiring reliable operation over extended periods. Additionally, germanium is less abundant and more expensive to refine and process compared to silicon, which affects its feasibility for widespread adoption in semiconductor manufacturing. These factors contribute to silicon’s dominance in the semiconductor industry despite germanium’s earlier historical use.
Germanium exhibits higher electrical conductivity than silicon primarily due to its narrower bandgap and higher intrinsic carrier concentration at room temperature. Intrinsic carrier concentration refers to the number of free electrons and holes available for conduction in a semiconductor material without external doping. Germanium’s narrower bandgap allows more electrons to move from the valence band to the conduction band at room temperature, resulting in higher conductivity compared to silicon. This property makes germanium suitable for certain specialized applications where high conductivity and unique electronic properties are advantageous, despite its limitations compared to silicon in mainstream semiconductor technology.