Ele533 Bipolar Devices
Final Exam 1998 Question 2

Figure 2   Na = 1018cm-3, a = 1023cm-4

The impurity profile of a pn junction is shown in figure 1. Na = 10¹⁸cm^-3, a = 10²³cm^-4

1. Sketch the space charge and electric field distributions.

2. If the critical electric field for breakdown is 5x10⁵V/cm, What is the total junction voltage(applied plus built-in) at breakdown?