Materials

• A Light Emitting Diode (LED) bulb is made from two different materials that conduct electricity, known as semiconductors. One of the two types of semiconductors has too many electrons in it, and the other one doesn't have enough. They are separated by a thin barrier that prevents the electrons from passing between the two under normal conditions.
  
  

Making the Bulb

• Once the two pieces of semiconductive material have been joined together and cut into small pieces, two wires are cut and attached to each piece. One wire provides a positive flow of electricity to the semiconductive base, while the other provides the negative flow. The base is then inserted into a translucent plastic cap that will broadcast the light. The base is glued to the cap.
  
  

Electrified

• The wires are hooked to a resistor, which is attached to a battery or other power source. The resistor keeps the power source from overloading the LED bulb. A switch that interrupts or completes the circuit allows the electricity to pass through the wires to the semiconductive base. The electricity causes electrons to pass from one part of the base to the other, releasing light along the way.
  
  

Keeping Cool

• A heat sink made of heat-absorbing material is glued to the bottom of the LED bulb before the bulb is finished. Often, the wires that connect the bulb to the power source are embedded in the heat sink to further reduce heat generated by the bulb.
  
  

Variations

• Depending on the types of semiconductor materials contained in the LED bulb and the amount of energy needed for each electron to jump from one to the other, the LED will emit different colors of light. Manufacturers produce organic LED lights in sheets that are cut into small pieces instead of gluing two different types of semiconductors together.