Techniques for forming instrumented cutting elements and affixing the instrumented cutting elements to earth-boring tools and related apparatuses and methods

An earth-boring tool, comprising:

• a cutting element brazed within a pocket extending into a body of the earth-boring tool, the cutting element comprising:
• a first hole extending over a first distance partially through the cutting element from a back side of the cutting element opposite a cutting face of the cutting element toward the cutting face, the first hole comprising a first maximum diameter;
• and
• a second hole extending over a second, shorter distance partially through the cutting element from the back side of the cutting element toward the cutting face, the second hole comprising a second, larger maximum diameter, the second hole in fluid communication with the first hole;
• an extension located at least partially within the second hole, the extension comprising a passageway extending through the extension and in fluid communication with the first hole;
• and
• a thermocouple extending through the passageway and into the first hole;
• and
• braze material affixing the cutting element within the pocket and exposed to a portion of the first hole located proximate to the back side of the cutting element and located on a lateral side of the second hole opposite a lateral side on which a remainder of the first hole proximate to the cutting face is located.

A method of forming an earth-boring tool comprising one or more instrumented cutting elements, the method comprising:

• brazing a cutting element in a pocket extending into a body of an earth-boring tool;
• exposing a portion of a first hole located proximate to a back side of the cutting element opposite a cutting face to flow of a braze material, the first hole extending over a first distance partially through the cutting element from the back side toward the cutting face, the first hole comprising a first maximum diameter;
• inhibiting flow of the braze material into a second hole and into a remainder of the first hole utilizing an extension located at least partially within the second hole, the second hole extending over a second, shorter distance partially through the cutting element from the back side of the cutting element toward the cutting face, the second hole comprising a second, larger maximum diameter the second hole in fluid communication with the first hole, the extension comprising a passageway extending through the extension and in fluid communication with the remainder of the first hole;
• and
• inserting a thermocouple through the passageway defined by the extension and into the remainder of the first hole.