ece340Spring04HW9Sol - ECE 340 Homework IX Due Wednesday...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
ECE 340 Homework IX Spring 2004 Due: Wednesday, March 03, 2004 1. An abrupt Si p-n junction is formed by alloying a uniformly doped n-type silicon bar where N d = 8x10 16 /cm 3 in the beginning. During the alloying process, a uniform counter doping of acceptors of N a = 1.4x10 17 /cm 3 is introduced in the region for x<0. Basically, x<0 is the p-side and x>0 is the n-side. (a) Calculate the Fermi level positions at 300 K in the p and n regions. (b) Draw an equilibrium band diagram for the junction and determine the contact potential V o from the diagram. (c) Compare the results of part (b) with V o as calculated from Eq. (5-8). (d) Using Eq. (5-8), calculate and plot V o versus temperature ranging from 250 K to 500 K. Solutions: (a), At x<0, 16 3 61 0 pad p NN c m =−= × In p region, 16 10 0 ln 0.0259 ln 0.394 1.5 10 ip Fp i kT p E Ee V qn × −= = × = × In n region, 16 10 81 0 ln 0.0259 ln 0.401 1.5 10 Fn in i kT n E V × = × = × (b), V 0 = 0.795 V (c), Equations 5-8: 16 16 0 22 0 81 0 0.0259ln 0.0259ln 0.795 ad ii VV nn ×× × == = Result is same as (b) (d), Notice that the n i is related to temperature through Eq. 3-26 Method 1: Read n i from Figure 3-17, plug into Eqn 5-8 to obtain the plot.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page1 / 4

ece340Spring04HW9Sol - ECE 340 Homework IX Due Wednesday...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online