P-type and n-type silicon wafers are two types of semiconductor wafers used in the manufacture of electronic devices such as transistors, diodes, and integrated circuits. The difference between the two types of wafers lies in the type of dopants added to the silicon crystal during the manufacturing process.
P-type silicon wafers are created by adding trivalent impurities, such as boron, to the silicon crystal. These impurities create “holes” in the silicon crystal lattice, which behave as positively charged carriers. This makes p-type silicon a type of semiconductor with a positive charge.
N-type silicon wafers, on the other hand, are created by adding pentavalent impurities, such as phosphorus or arsenic, to the silicon crystal. These impurities create extra electrons in the silicon crystal lattice, which behave as negatively charged carriers. This makes n-type silicon a type of semiconductor with a negative charge.
The use of p-type and n-type silicon wafers allows for the creation of p-n junctions, which are essential for the operation of many electronic devices. When a p-type and an n-type semiconductor are brought into contact, electrons from the n-type semiconductor flow into the holes in the p-type semiconductor, creating a region of excess negative charge on the n-side and excess positive charge on the p-side. This creates a built-in electric field, which can be used to control the flow of current through the device.
