1-17
Figure 1-14A.—The point-contact type of diode construction.
Figure 1-14B.—The point-contact type of diode construction.
Still another process is to heat a section of semiconductor material to near melting and then diffuse
impurity atoms into a surface layer. Regardless of the process, the objective is to have a perfect bond
everywhere along the union (interface) between P and N materials. Proper contact along the union is
important because, as we will see later, the union (junction or interface) is the rectifying agent in the
diode.
Q19. What is the purpose of a PN junction diode?
Q20. In reference to the schematic symbol for a diode, do electrons flow toward or away from the
arrow?
