Back drilling vias of a printed circuit board

A method of forming vias of a printed circuit board (PCB), the method comprising:

• drilling of a particular via from a first side of the printed circuit board (PCB) with a first drill bit having a first diameter to form the particular via, the particular via being formed to have a particular diameter that is equal to the first diameter;
• back drilling of the particular via from a second side of the PCB, the second side being disposed opposite of the first side of the PCB, the back drilling including:
• back drilling of the particular via with a second drill bit having a second diameter, the second diameter a first percentage greater than the particular diameter of the particular via at the first side of the PCB;
• determining whether the second diameter of the second drill bit is a threshold percentage greater than the particular diameter of the particular via at the first side of the PCB;
• determining that the second diameter of the second drill bit is less than the threshold percentage greater than the particular diameter of the particular via at the first side of the PCB, and in response:
• back drilling of the particular via with a third drill bit having a third diameter, the third diameter a second percentage greater than the particular diameter of the particular via at the first side of the PCB, the third diameter greater than the second diameter;
• determining whether the third diameter of the third drill bit is the threshold percentage greater than the particular diameter of the particular via at the first side of the PCB;
• and
• determining that the third diameter of the third drill bit is less than the threshold percentage greater than the particular diameter of the particular via at the first side of the PCB, and in response, back drilling of the particular via with a fourth drill bit having a fourth diameter, the fourth diameter greater than the third diameter,
• wherein the particular via is plated,
• wherein back drilling of the particular via includes removing a portion of the plated particular via between the second side of the PCB and a distance between the first side of the PCB and the second side of the PCB.