There is a certain value in this paper for understanding semiconductor manufacturing

As science and technology continue to advance, people are becoming more reliant on versatile digital devices. wafer prober Bluetooth headsets, smartphones, smart TVs, and even smart refrigerators have become essential parts of our daily lives. These advanced products constantly shape our routines. However, it is important to acknowledge that the small chip plays a significant role in creating these experiences. We also owe our current level of convenience to the ongoing development and evolution of semiconductor industry processes. Join me as we explore the history of semiconductor chips.

Semiconductors: what are they?

Semiconductor definition

Materials can be divided into three categories based on their electrical conductivity: conductors, insulators, and semiconductors.

Material with a conductivity greater than 103s/cm, such as gold, silver, or copper

Silicon, germanium, and boron are semiconductors, which fall between electrical conductivity and resistance

Materials with a conductivity less than 10-8 s/cm, such as glass and plastic, are insulators

The band structure theory derived from quantum computational mechanics can also be used to analyze it. We can see from the figure below that the band-gap width of the insulator is about 9eV, the band-gap width of the semiconductor is about 1eV, and there is basically no overlap between the conduction band and the valence band of the conductor.

Semiconductor classification

Semiconductors can also be divided based on their composition:

Semiconductors are classified as elements, such as germanium, silicon, and so on. probe test Nowadays, semiconductors are mainly silicon, which we use in our everyday lives.

A compound semiconductor consists of two or more elements, such as gallium arsenide.

As a semiconductor, glass is an amorphous semiconductor, wafer probing which can either be oxidized or not oxidized.

The semiconductor industry uses elemental semiconductors to prepare chips, and the semiconductor chip we can often use is a very large integrated system circuit.

Technical Requirements, Part 2

Technology that is ultra-clean

At present, dust particles can be controlled at a nanometer level to achieve pollution-free production. To accomplish this, it is necessary to strictly control the dust in the working environment. Using the 0.25 process, 1 cubic meter of air diameter greater than 0.1 micron dust cannot exceed 100 particles.

Purity at the highest level

Materials, gases, and reagents used in the manufacturing process must be ultra-pure. At present, harmful impurities can be controlled to a maximum of PPB(billion).

Technology for ultra-fine processing

Micromachining is a general term for processing micron or submicron linewidth materials, which includes crystal growth and thin layer generation, microscopic image processing, and precision control doping. As a result of these technical levels, the diameter of the substrate material and the tiny size of each component determine the integration of an integrated circuit.

The previous process in Part 3 of the FEOL

The production process of semiconductor manufacturing can be divided into front process and back process. In semiconductor manufacturing, the front process research is of the utmost importance, and the technical difficulties are numerous, the operating system is complicated, and it is the core of the entire process. As we proceed, we will discuss the important technologies and processes in the previous path sequentially.

Processing of wafers

Before we can make a chip, we need to make a qualified wafer first. Semiconductor technology starts with a grain of sand. To make high-quality wafers, we first need to extract high-purity monocrystalline silicon wafers from silica sand with a silica content of more than 95%. There are three steps to creating a wafer:

Casting of ingots

After heating silica sand to remove impurities, high purity electronic grade silicon is obtained by a series of processes including dissolution, purification, and distillation. By using the czochralase method, molten monocrystalline silicon was solidified into rod-like ingots.

Cutting of ingots

Diamond saws are used to cut the ends of the ingot, and the ingot is then cut into slices of a certain thickness. The diameter of the ingot determines the size of the wafer.

Polishing of wafer surfaces

In order to use such wafers directly, their surfaces must first be ground and chemically etched to remove defects, and then polished and cleaned to smooth and complete the surface.