EE143 Microfabrication Technology 1 19 10 C Nguyen Lecture 1 Administration Overview History of IC s Administration Overview This Lecture Administration Overview Reading Handouts Lecture Topics Course information Syllabus Welcome to EE 143 Microfabrication Technology This is our course on wafer level fabrication of transistor integrated circuits and other microdevices such as MEMS Pass out course info sheet Pass out course syllabus Lab juggling get info on the order of people signing up for labs then only make those who were last in a section that is full move must show data on lab section counts on first lecture sheet Show calendar and settle the office hours Goals of the course Teach the skills needed to design and fabricate micro and nano devices including integrated circuits and micro electromechanical systems MEMS Design emphasis This is NOT a survey course you will be expected to design and layout physical MOS devices and MEMS devices if there s time Hands on emphasis Give you actual hands on experience fabricating micro devices using a wafer level process in a cleanroom The mechanics of the course are summarized in the course handouts given out in lecture today Course Information Sheet Course description Course mechanics Textbooks Grading policy Syllabus Lecture by lecture timeline w associated reading sections Midterm Exam Thursday March 18 tentative Final Exam Monday May 10 Copyright 2009 Regents of the University of California IC History Review of Devices Reading Jaeger Chpt 1 Lecture Topics History of IC s Devices of Interest MOS transistor Micromechanical structure History of IC s 1834 Difference Engines mechanical computers Gears cranks levers decimal pipelining 1904 Vacuum tube invented Yielded the ENIAC vacuum tube computer 1925 J Lilenfield proposed the MOSFET transistor Problem knowledge of materials not sufficient to get this to work instead 1947 Invention of the transistor Bardeen Brattein Shockley 1949 Invention of the Bipolar Xsistor Shockley 1956 First digital logic gates Harris 1959 Invention of planar silicon processing Kilby Noyce Then a slew of bipolar technologies 1 EE143 Microfabrication Technology 1 19 10 C Nguyen Lecture 1 Administration Overview History of IC s TTL 1965 ECL 1967 MTL I2L 1972 SiGe heterostructures 1990 s Bipolar ruled during the 60 s and 70 s because it was faster than anything else incl MOS But soon its excessive power consumption caught up and MOS began to come into favor as small channel lengths boosted the speed of MOS Fairly simple process only 5 masks note that this is much smaller than today s proess which might have more than 28 masking steps The rise of MOS occurred in steps 1965 PMOS w Al gate Used 111 wafers because bipolar used them This forced the use of PMOS since oxide charge was dense in 111 Si to oxide interfaces Oxide charge made it difficult to isolate NMOS devices 1967 70 Al gate NMOS Use of 100 Si together with sintering reduced oxide charges Speed faster than PMOS and path to matching bipolar speed could be seen Copyright 2009 Regents of the University of California 2 EE143 Microfabrication Technology 1 19 10 C Nguyen Lecture 1 Administration Overview History of IC s 1970 Si gate NMOS Advantage self alignment of source drain Problem power consumption similar to bipolar To reduce power consumption a complementary device was needed This is where CMOS looked advantageous Copyright 2009 Regents of the University of California 1963 pwell CMOS CMOS gate actually came before NMOS or PMOS but poor control of oxide quality at the time prevented it from thriving Why didn t CMOS thrive in 1963 1 Higher fabrication cost 2 Latch up problems 3 Lower packing density due to need for wells 4 CMOS slower than NMOS due to larger gate capacitance But soon power became an issue 1971 Intel 4004 4 bit microprocessor 2 300 devices PMOS 1978 Intel 8086 16 bit microprocessor 29 000 devices NMOS power dissipation beginning to get up there 1 5W 8MHz 1985 Intel 80386 275 000 devices NMOS light bulb A low power technology was needed Result CMOS takes over Intel 80C86 CMOS version of 80386 Intel 80486 1 2 million Xsistors Intel Pentium P5 3 million Xsistors Intel P6 5 5 million Xsistors in core 15 million more in secondary cache And of course it keeps going to today Intel Core 2 Duo 820 million Xsistors 3
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