Silicon doped with electron electron elements of group-13 forms.

p-type semiconductor

The correct answer is option 3. p-type semiconductor.

Doping is a process used to intentionally introduce impurities into a semiconductor material to modify its electrical properties. When silicon, which is a group 14 semiconductor, is doped with elements from group 13 of the periodic table (such as boron, aluminum, or gallium), which have one less valence electron than silicon, it creates what is known as a p-type semiconductor.

Group 13 elements have only three valence electrons, whereas silicon has four valence electrons. When a small amount of a group 13 element is introduced into the silicon crystal lattice during the crystal growth process, it replaces some of the silicon atoms. These group 13 atoms have one less valence electron compared to silicon, creating "holes" in the crystal lattice.

The introduction of group 13 elements creates "holes" in the silicon crystal lattice. These holes represent missing electrons in the covalent bonds between silicon atoms. In a sense, they behave as positively charged carriers because neighboring electrons can move into these holes, leaving behind new holes.

Due to the presence of these holes, silicon doped with group 13 elements becomes a p-type semiconductor. The majority charge carriers in p-type semiconductors are holes rather than electrons. When a small voltage is applied across a p-type semiconductor, current is carried by the movement of these positively charged holes.

In summary, doping silicon with group 13 elements results in the formation of a p-type semiconductor, where the majority charge carriers are positively charged holes. This type of semiconductor is essential for the functioning of various electronic devices, including diodes and transistors.