This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: N.CHEUNG, Sp 2008 EECS243: ADVANCED IC PROCESSING AND LAYOUT Homework Assignment #4 (Due March 5 Wed) Reading Assignment : Start with Plummer Chap 3.5.4 (point defects) Plummer Chap 7 Plummer Chap 4.23,4.33,4.43,4.53 (on Gettering) EE243 Lecture Notes Problem 1 Ratio of lateral junction depth / vertical junction depth Let C max be the maximum concentration of the diffusion profile and N B be the substrate concentration.With diffusion mask covering half of the Si wafer, the 2-dimensional drive-in doping concentration is given by: C(x,y,t) = Q 2 π Dt e -x 2 /4Dt [ 1 +erf ( y 2 Dt ) ] (a) Derive an expression for the ratio of lateral junction depth y j over the vertical junction depth x j in terms of N B /C max . Diffusion Mask (0,0) y x-y j x j Substrate (N /cm3) B (b) Calculate and plot the ratio y j / x j (linear scale) versus N B /C max from 10-5 to 10-2 (log 10 scale) (Hint: You can find the erf function properties in the appendix page of this HW) Problem 2 Oxidation enhanced diffusion The following simulation result is taken from your textbook (PDG) to explain OED for Boron and ORD for Sb. (i) What is the physical origin that...
View Full Document
This note was uploaded on 11/02/2010 for the course EECS 243 taught by Professor Ee243 during the Spring '03 term at University of California, Berkeley.
- Spring '03