Although silicon (Si) cannot be replaced in integrated circuit chip manufacturing at present, after so many years of development, each mature semiconductor material can drive the development of its own industry. So what semiconductor materials are currently available in the industry?
First-generation semiconductors:
The industry has classified semiconductor materials, with silicon (Si) and germanium (Ge) mentioned earlier being first-generation semiconductor materials.
Silicon (Si): As mentioned earlier, silicon (Si) is currently the most widely used semiconductor material, and integrated circuits are basically made of silicon (Si). Silicon (Si) is widely known because it is the material for CPUs; Intel and AMD processors are both based on silicon (Si). Of course, besides CPUs, GPU chips and flash memory are also dominated by silicon (Si).
Germanium (Ge): Germanium (Ge) was an early material for transistors. It can be said that Germanium (Ge) declined after the advent of silicon (Si). However, Germanium (Ge) was not completely replaced by silicon (Si). As one of the important semiconductor materials, Germanium (Ge) is still active in some optical fiber, solar cell and other channel fields.
The first generation of semiconductor materials was the most mature in terms of both technology development and cost control. Therefore, even though the second and third generation of semiconductor materials completely surpassed silicon (Si) in certain performance characteristics, they could not commercially replace the value of silicon (Si) and could not bring the same high returns as silicon (Si).
Second-generation semiconductors:
Second-generation semiconductor materials are fundamentally different from first-generation semiconductors. First-generation semiconductors, such as silicon (Si) and germanium (Ge), are elemental semiconductors, meaning they are composed of a single substance. Second-generation semiconductors, on the other hand, are compound semiconductors, synthesized from two or more elements, and possess semiconductor properties. Common second-generation semiconductors include gallium arsenide (GaAs) and indium phosphide (InP).
Gallium arsenide (GaAs): Gallium arsenide (GaAs) is one of the landmark products of second-generation semiconductor materials. The LED light-emitting diode that we often hear about contains gallium arsenide (GaAs).
Indium phosphide (InP): Indium phosphide (InP) is produced by heating metallic indium and red phosphorus in a quartz tube. It is characterized by high temperature resistance, high frequency and high speed, so it is widely used in the communications industry to make communication devices.
Second-generation semiconductors can be considered the foundation of the 4G era, and many 4G devices use materials based on second-generation semiconductor materials.
Third-generation semiconductors:
Third-generation semiconductors also belong to compound semiconductor materials, characterized by high bandgap, high power, high frequency, and high voltage. Representative products are silicon carbide (SiC) and gallium nitride (GaN).
Silicon carbide (SiC): Silicon carbide (SiC) has the characteristics of high temperature resistance and high voltage resistance, making it very suitable for making power device switches. For example, many high-end MOSFETs on motherboards are made of silicon carbide (SiC).
Gallium nitride (GaN): Like silicon carbide (SiC), gallium nitride (GaN) is a high bandgap semiconductor. Its characteristics include low power consumption and suitability for high frequencies, making it suitable for building 5G base stations. The only drawback is that the technology cost is too high, making it difficult to see in the commercial field.
Currently, the development of third-generation semiconductors is being promoted in China because the gap between domestic and foreign starting points is small, and there is still room for competition.
Precautions:
Although these semiconductor materials are considered to be classified into first-generation and second-generation, which sounds like iterative products, these first-generation, second-generation, and third-generation semiconductor materials are not replacements. They have different characteristics and different application scenarios. The first, second, and third generations are just a distinction made by the industry based on the materials. In some scenarios, they are even used together.
