Why Silicon is used for chips?

Si forms the basic starting material for IC. It is a Group IV element. 

*Pure Si is a poor conductor of electricity.

Advantages:

1. Cheap and extremely abundant in nature which makes it affordable.

2. Operates better at higher temperatures.

Disadvantages:

1. Lower carrier mobility compared to Ge and GaAs.

2. Hence, not preferred for ultra-high-speed transistors.