Electrons - Microelectronic Devices and Circuits - Solved Exam, Exams of Microelectronic Circuits

Download Electrons - Microelectronic Devices and Circuits - Solved Exam and more Exams Microelectronic Circuits in PDF only on Docsity! EECSIOS 1of8 Fall 2000 | Microelectronic Devices and Circuits- EECS105 | First Midterm Exam | Wednesday, October 11, 2000 Costas J. Spanos University of California at Berkeley College of Engineering Department of Electrical Engineering and Computer Sciences Your Name: tie Soburions ast) (frst) €. 4. SPAMS . Your Signature 1. Print and sign your name on this page before you start, 2. You are allowed a single, handwritten sheet with formulas, No books or notes! 3, Do everything on this exam, and make your methods as clear as possible Problem I £35 Problem 2 /35 Problem3_/ 15 Problem 4 mer) — yy roraL { FL) /100f 45 EECSIOS 2 0f8 Fall 2000 Problem 1 of 4 (35 points) ‘Answer each question briefly and clearly, Assume room temperature and thermal equilibriura unless otherwise noted. Whit types and concentrations of charges exist in intrinsic silicon? (6pts) ne 10" fom? (bee edberivs) pe to feu (foe hofes) List che type (hotes, electrons, ions), sign (4/-} and concentrations of all charges in silicun doped with 10'om? As and 10 om? Boron. Be sure ta mention whether each charge is mobile or not. (8pts) As domiaoves, so morerlol is n-type we hae lO eleams fo, — jo? holes Jie} cad vlro we Ie ’ t iol? purttbue As lous ftom? oad 10 negara B fous Jem? ‘What ave the four types of currents you can fiud across a p-n junction in thermal equilibrium? (6pts) yn : sr + yan . yu -o0 a  RECSIO5 30f8 Fall 2009 Ting the comtact-to-vontast resistance of the following structure (drawn to scale), it the I&s is 10 Olmsisquare, Assume that “dogbone” contact areas amount to 6.65 squares. (Spts) oa oss we hoe x trol of 93D x 10%/g - $30.8 You are given doped silicon that at thermal equilibrium has an electron concentration 10'fem* What is the built-in potential with reference to intrinsic silicon? What would be the concentration of electrons at some point within this Initice, iF you raised the potential at thal point by 120mV? (pts) , 2 6x 6Omy 2 360m na toned the poteatlal to 3600 4 nV 5 Aiba shen th tonc3on tran of ebbtrrous nould be Jo! ian to soristy the 62nV rule EECSIOS 40f8 Falf 2008 Problem 2 of 4 (35 points) Consider the following structure that consists of n-type silicon (10'4’em?), 0.1j8m of SiO and p- type silicon (10!/em>}, (dint: This is nothing more than a MOS capacitor whuse gate is made out of weakly doped silicon, This means that the gate will also deplete and‘or invert under proper conditions. The symmetric concentrations in the channel and the gate should mate this problent aqsy to solve...) ¥d (gate) Xda ulk) i rt a | a Je-—| Si02 —s| er a, Caleulate the depth of the depletion regions when Vgg ~ 0. (10pts) in themok eguibibarem me have: QM Xda DM Xd” 2 Wakdn 5. Pye Gn = SP 2B ve Cox shop across the Ww drop aero HEP agp wezoss Cox - depletion deplerion subshitare, Ga OS0V, fps 086, 9: 16:10 %Cb, Ma Wh 10'Tom?® Yad: Xd, tad Cop 2% 2 3.4587 Fame fox Ad «1 Bt MY Kae O72 20 ey Nays “bE MEH a, fy es wo 7a a b ec shate system Do Sys emt: Xp = Oe per ——