Chapter 1: Introduction

Current market situation

In 2024, global consumer electronics market sales were between $1.2 billion and $1.3 billion. With a predictive CAGR of ~6.6% through 2030. Whereas, Global semiconductor sales were clocked at just below $700 billion. Due to multi-billion USD investements and local government's incentive towards "Semicon India", India seems to be the fastest growing semiconductor market with a projected CAGR of 13-15% through 2025-2030.

Short historical timeline

• 1958: Jack Kilby from Texas Instruments invented the first Germanium (Ge) based IC.
• 1959: Robert Noyce from Fairchild Semiconductor modified it to Si-based IC, bringing this technology closer to high-volume manufacturing (HVM).
• 1980: Beginning of Computer Integrated Monitoring of ICs (IC-CIM), which improved productivity in the IC manufacturing process.

Introduction to p-n junction fabrication process

A p-n junction diode is one of the most fundamental semiconductor devices. It consists of two regions of doped semiconductor material:

• P-type region: Rich in holes (positive charge carriers).
• N-type region: Rich in electrons (negative charge carriers).

When these two regions are joined, they form a P-N junction, giving the diode its unique electrical characteristics.

In p-n junctions, SiO2 film is used to define the junction area and can provide functionalities such as an insulator, a diffusion barrier, or an implantation barrier. There are two ways to grow SiO2 layers:

• Dry oxidation (O2 gas) for thin films, with good interfacial properties between Si-SiO2
• Wet oxidation (H2O vapor) for thick films, as high growth rates, can be obtained with this process.

The fabrication schematic of the p-n junction is provided below.

Goals of Manufacturing

• Low cost of production
• High quality 
• High reliability

1) Cost of production

• The cost of IC manufacturing is roughly divided equally between fabrication, testing, and packaging.
• IC fabrication cost ~  $4/cm2 (excluding design cost) at mature production levels.
• Cost minimization can be carried out by
• Maximizing yield
• Maximising number of chips/wafer
• Cost of IC to produce N chips ~ e^(kN), where k represents the cost of assembly and testing and is represented in figure below.

2) Quality

• Quality of design
• Represents the choice of fabrication material, component specification, product size, and other features
• Quality of conformance
• Represents how well the product conforms to required specifications.
• Impacted by manufacturing process, equipment performance, competence and training of workforce, and quality control.

Manufacturing Systems

Two types:

1) Continuous flow manufacturing

• Refers to a chemical/physical process that changes the state of the part before it is connected to other components to form a finished product. Example: IC fabrication process before wafer dicing and packaging.
• Two types
• Batch process: a process that operates on multiple products or batches (aka "lots") simultaneously. Example: CVD of a whole lot.
• Pro: faster processing
• Con: difficult to control parameters
• Single workpiece (wafer) processes: individual wafer processed one at a time.
• Pro: Easier to control parameters
• Con: slow processing

2) Discrete-part manufacturing:

• Assembly of distinct pieces to yield a final product. Example: Printed circuit board (PCB) assembly using individual ICs.

Chapter 1 provided a quick summary of the semiconductor market situation and important aspects of IC fabrication process. In the next chapter, we will dive deeper into the technical features of the different processes required for the IC fabrication.