半导体制造工艺讲义 第二章 集成电路制造介绍.pdf

Hong Xiao, Ph. D. www2.austin.cc.tx.us/HongXiao/Book.htm 1 Chapter 2 Introduction of IC Fabrication Hong Xiao, Ph. D. hxiao89@ Hong Xiao, Ph. D. www2.austin.cc.tx.us/HongXiao/Book.htm 2 Objectives ? Define yield and explain its importance ? Describe the basic structure of a cleanroom. ? Explain the importance of cleanroom protocols ? List four basic operations of IC processing ? Name at least six process bays in an IC fab ? Explain the purposes of chip packaging ? Describe the standard wire bonding and flip-chip bump bonding processes Hong Xiao, Ph. D. www2.austin.cc.tx.us/HongXiao/Book.htm 3 Wafer Process Flow Materials Design Masks IC Fab Test Packaging Final Test Thermal Processes Photo- lithography Etch PR strip Implant PR strip Metallization CMP Dielectric deposition Wafers Hong Xiao, Ph. D. www2.austin.cc.tx.us/HongXiao/Book.htm 4 Fab Cost ? Fab cost is very high, $1B for 8” fab ? Clean room ? Equipment, $1M per tool ? Materials, high purity, ultra high purity ? Facilities ? People, training and pay Hong Xiao, Ph. D. www2.austin.cc.tx.us/HongXiao/Book.htm 5 Wafer Yield total good W Wafers Wafers Y = Hong Xiao, Ph. D. www2.austin.cc.tx.us/HongXiao/Book.htm 6 Die Yield total good D Dies Dies Y = Hong Xiao, Ph. D. www2.austin.cc.tx.us/HongXiao/Book.htm 7 Packaging Yield total good C Chips Chips Y = Hong Xiao, Ph. D. www2.austin.cc.tx.us/HongXiao/Book.htm 8 Overall Yield YT = YW×YD×YC Overall Yield determines whether a fab is making profit or losing money Hong Xiao, Ph. D. www2.austin.cc.tx.us/HongXiao/Book.htm 9 How Does Fab Make Money ? Cost: – Wafer (8”): ~$150/wafer* – Processing: ~$200 (1$/wafer, 200 process steps) – Packing: ~$1/chip ? Sale: – ~100 chips/wafer – ~$50/chip (low-end microprocessor in 2000) *Cost of wafer and price of chip are changing daily, numbers are choosing randomly based on general information. Hong Xiao, Ph. D. www2.austin.cc.tx.us/HongXiao/Book.htm 10 How Does a Fab Make (Loss) Money ? 100% yield: 150+200+100 = $450/wafer ? 50% yield: