Silicon Oxidation Explained: Essential Process for Modern IC Technology

Complete guide to silicon oxidation processes by Dr. G.S. Virdi, Ex. Chief Scientist at CSIR-Central Electronics Engineering Research Institute, Pilani.
What you'll learn:
✓ Introduction to semiconductor oxidation methods
✓ Thermal oxidation: the key process in modern silicon IC technology
✓ Oxidation furnace setup and operation (800-1200°C)
✓ Dry oxidation process using O₂ gas
✓ Wet oxidation process using H₂O vapor
✓ Comparative advantages and disadvantages of each method
✓ Practical applications in IC fabrication
Key Topics Covered:

Classification of oxidation processes
Dry oxidation: Si + O₂ → SiO₂ (uniform, high-quality oxide layers)
Wet oxidation: Si + 2H₂O → SiO₂ + 2H₂ (faster growth rate)
Oxidation furnace components and operation
Boron and Phosphorus predeposition and drive-in processes
When to use thick vs thin oxide layers

Process Details:

Temperature range: 800-1200°C
Oxide thickness: 0.01-1.0 μm
Atmospheric pressure operation in open tube quartz furnace

Ideal for students, engineers, and professionals in semiconductor manufacturing, microelectronics, VLSI design, and materials science.
#Oxidation #SiliconOxide #ICFabrication #SemiconductorManufacturing #VLSI #Microelectronics #ThermalOxidation #ChipManufacturingRetryClaude can make mistakes. Please double-check responses.

1. Dr. G.S. Virdi Ex. Chief Scientist CSIR- Central Electronics Engineering Research Institute Pilani- - 333031, India 1 OXIDATION

2. Introduction Oxidation of silicon Classification of oxidation process Advantages and disadvantages Application G.S.VIRDI 2 CONTENT

3. Semiconductor can be oxidized by various methods, including Thermal oxidation, electrochemical anodization 3 3 and plasma enhanced chemical vapour deposition. A m ong the s e the r m al oxida t ion is m ost co mm only used. It is a key process in m odern si l icon IC te c hnolog y . G.S.VIRDI 3 INTRODUCTION

4. The most widely used technique to grow SiO ₂ on silicon is Thermal oxidation. This is usually carried out in an open tube qu a rtz furnace at atmospheric pressure between 800- 1200 ℃ . G.S.VIRDI 4 Oxidation of silicon

5. When a silicon heated in a furnace at a high temperature in the presence of oxygen gas. This oxidation process carried out in the furnace which is called an oxidation Furnace . Schematic of an oxidation Furnace Schematic of an oxidation Furnace G.S.VIRDI 5 Oxidation Furnace

6. 6 Boron Predeposition Boron Drive- in Phosphorus Predeposition Phosphorus Drive- in G.S.VIRDI Oxidation Furnace

7. Pictorial description of oxidation process 7 Si Wafer Si Wafer Si Wafer O₂ or H₂O 800- 1200 ℃ 0.0.1- 1.0μm SiO₂ G.S.VIRDI

8. Classification of oxidation process : 8 There are two type fabrication namely , Dry Oxidation 🞍 Wet Oxidation of oxidation process used in G.S.VIRDI

9. Growth of SiO ₂ using O ₂ is referred to as Dry oxidation. In Dry oxidation –oxygen is passed through the tube where it react with silicon to form SiO ₂ Reaction : Si +O ₂ SiO ₂ G.S.VIRDI 9 Dry Oxidation

10. Advantage: Oxide layer are very uniform. Relatively few defects exist at oxide interface Disadvantage : Dry oxide grows s l o wl y . G.S.VIRDI 10 Dry Oxidation

11. High purity de- ionised water, kept in a quartz bubbler at inlet of the furnace, is heated to a temperature close to its boiling point High purity oxygen or nitrogen is passed through it so that the gas flow into furnace is saturated with water vapour. Water then acts as the oxidizing agent and the oxidation reaction is given by Si +2H ₂ O SiO ₂ +2H ₂ G.S.VIRDI 11 Wet Oxidation

12. Advantage: Wet oxide grows fast. Disadvantage : Hydrogen atom liberated by decomposition of w a ter molecules produce perfections that may degrade the oxides quality. G.S.VIRDI 12 Wet Oxidation

13. The oxidation rate of wet oxidation is significantly higher than that of dry oxidation hence, whenever thickness oxide is needed, wet oxidation process is used. 🞂 ​ Wet oxidation –Thick oxide layer 🞂 ​ Dry oxidation-Thin oxide layer G.S.VIRDI 13 APPLICATIONS

14. Thank You… G.S.VIRDI 14