1、,Semiconductor Manufacturing TechnologyMichael Quirk & Julian Serda October 2001 by Prentice HallChapter 10 Oxidation, 2000 by Prentice Hall,Semiconductor Manufacturing Technologyby Michael Quirk and Julian Serda,Objectives,After studying the material in this chapter, you will be able to:1.Describe
2、an oxide film for semiconductor manufacturing, including its atomic structure, how it is used and its benefits.2.State the chemical reaction for oxidation and describe how oxide grows on silicon.3.Explain selective oxidation and give two examples.4.State the three types of thermal processing equipme
3、nt, describe the five parts of a vertical furnace, and give the attributes of a fast ramp vertical furnace.5.Explain what is a rapid thermal processor, its usage and design.6.Describe the critical aspects of the oxidation process, its quality measures and some common troubleshooting problems.,Diffus
4、ion Area of Wafer Fabrication,Used with permission from Advanced Micro Devices,Figure 10.1,Oxide Film,Nature of Oxide FilmUses of Oxide FilmDevice Protection and IsolationSurface PassivationGate Oxide DielectricDopant BarrierDielectric Between Metal Layers,Atomic Structure of Silicon Dioxide,Used wi
5、th permission from International SEMATECH,Figure 10.2,Field Oxide Layer,Figure 10.3,Gate Oxide Dielectric,Figure 10.4,Oxide Layer Dopant Barrier,Figure 10.5,Table 10.1Oxide Applications: Native Oxide,Table 10.1A,Table 10.1 Oxide Applications: Field Oxide,Table 10.1B,Table 10.1 Oxide Applications: Ga
6、te Oxide,Purpose: Serves as a dielectric between the gate and source-drain parts of MOS transistor.,Comments: Growth rate at room temperature is 15 per hour up to about 40 . Common gate oxide film thickness range from about 30 to 500 . Dry oxidation is the preferred method.,Table 10.1C,Table 10.1 Ox
7、ide Applications: Barrier Oxide,Table 10.1D,Table 10.1 Oxide Applications: Dopant Barrier,Table 10.1E,Table 10.1 Oxide Applications: Pad Oxide,Table 10.1F,Table 10.1 Oxide Applications: Implant Screen Oxide,Table 10.1G,Table 10.1 Oxide Applications: Insulating Barrier between Metal Layers,Table 10.1
8、H,Thermal Oxidation Growth,Chemical Reaction for OxidationDry oxidationWet oxidationOxidation Growth ModelOxide silicon interfaceUse of chlorinated agents in oxidationRate of oxide growthFactors affecting oxide growthInitial growth phaseSelective oxidationLOCOSSTI,Oxide Thickness Ranges for Various
9、Requirements,Table 10.2,Dry Oxidation Time (Minutes),Figure 10.6,Wet Oxygen Oxidation,Figure 10.7,Consumption of Silicon during Oxidation,Figure 10.8,Liquid-State Diffusion,Figure 10.9,Charge Buildup at Si/SiO2 Interface,Used with permission from International SEMATECH,Figure 10.10,Diffusion of Oxyg
10、en Through Oxide Layer,Figure 10.11,Linear & Parabolic Stages for Dry Oxidation Growth at 1100C,Used with permission from International SEMATECH,Figure 10.12,LOCOS Process,Figure 10.13,Selective Oxidation and Birds Beak Effect,Used with permission from International SEMATECH,Figure 10.14,STI Oxide L
11、iner,Figure 10.15,Furnace Equipment,Horizontal FurnaceVertical FurnaceRapid Thermal Processor (RTP),Horizontal and Vertical Furnaces,Table 10.3,Horizontal Diffusion Furnace,Photograph courtesy of International SEMATECH,Photo 10.1,Vertical Diffusion Furnace,Photograph courtesy of International SEMATE
12、CH,Photo 10.2,Block Diagram of Vertical Furnace System,Figure 10.16,Vertical Furnace Process Tube,Figure 10.17,Heater Element Power Distribution,Used with permission from International SEMATECH,Figure 10.18,Locations of Thermocouples in the Furnace Chamber,Figure 10.19,Common Gases used in Furnace P
13、rocesses,Table 10.4,Burn Box to Combust Exhaust,Used with permission from International SEMATECH,Figure 10.20,Thermal Profile of Conventional Versus Fast Ramp Vertical Furnace,Reprinted from the June 1996 edition of Solid State Technology, copyright 1996 by PennWell Publishing Company.,Figure 10.21,
14、Fast Ramp,Conventional,The Main Advantages of a Rapid Thermal Processor,Reduced thermal budgetMinimized dopant movement in the siliconEase of clustering multiple toolsReduced contamination due to cold wall heatingCleaner ambient because of the smaller chamber volumeShorter time to process a wafer (r
15、eferred to as cycle time),Comparison of Conventional Vertical Furnace and RTP,Table 10.5,Rapid Thermal Processor,Figure 10.22,Rapid Thermal Processor,Photograph courtesy of Advanced Micro Devices, Applied Materials 5300 Centura RTP,Photo 10.3,RTP Applications,Anneal of implants to remove defects and
16、 activate and diffuse dopantsDensification of deposited films, such as deposited oxide layers Borophosphosilicate glass (BPSG) reflow Anneal of barrier layers, such as titanium nitride (TiN)Silicide formation, such as titanium silicide (TiSi2)Contact alloying,Oxidation Process,Pre Oxidation Cleaning
17、Oxidation process recipeQuality MeasurementsOxidation Troubleshooting,Critical Issues for Minimizing Contamination,Maintenance of the furnace and associated equipment (especially quartz components) for cleanlinessPurity of processing chemicalsPurity of oxidizing ambient (the source of oxygen in the
18、furnace)Wafer cleaning and handling practices,Thermal Oxidation Process Flow Chart,Figure 10.23,Process Recipe for Dry Oxidation Process,Table 10.6,Wafer Loading Pattern in Vertical Furnace,Figure 10.24,Used with permission from International SEMATECH,Chapter 10 Review,Quality Measures250Troubleshooting252Summary252Key Terms253Review Questions253Equipment Suppliers Web Sites254References255,
