Dielectric materials for semiconductor chips

Little funda about dielectric material:

Dielectric material characterize with very low electrical conductivity (one millionth of a mho / cm), in which an electric field can be sustained with a minimal leakage. It can store electrical energy/charge.

The electrically sensitive molecules inside dielectric material called polar molecules align by a pattern whenever external electric voltage is applied. The polar molecules align with the field so that the positive charges accumulate on one face of the dielectric and the negative charges on the other face.

Dry air is a good example of a dielectric material but is a poor dielectric. Most of the dielectric materials are solid such as porcelain (ceramic), glass, mica, plastics, and the oxides of various metals. Some liquids and gases can also good dielectric properties, vaccum and distilled water are also dielectric materials.

Dielectric material is popularly used in capacitors to reduce the size of the capacitor. The ceramic and plastic film capacitors are good examples. Another major application of Dielectric materials is in semiconductor chips to insulate transistors from each other. Dielectric materials are also used in various other electrical and electronic components.

Why the dielectric material is used in capacitor?

Dielectric material offers mechanical strength
By factor x the cap...