Semiconductor physics
Which value is closest to the atomic density of crystalline silicon?
- AAbout 5×10¹⁰ cm⁻³
- BAbout 5×10¹⁶ cm⁻³
- CAbout 5×10²² cm⁻³
Show answer and explanation
Answer: C. About 5×10²² cm⁻³
The atomic density of crystalline silicon is about 5×10²² cm⁻³. For example, doping with 1×10¹⁶ cm⁻³ donors means roughly one donor atom per five million silicon atoms. This shows how tiny amounts of impurities can greatly change a semiconductor's properties.