Predictions and Challenges of Fifth-Generation Semiconductor Materials
April 29, 2025
Predictions and Challenges of Fifth-Generation Semiconductor Materials
Semiconductors are the cornerstone of the information age, and the iteration of semiconductor materials directly defines the boundaries of human technological advancement. From first-generation silicon-based semiconductors to today’s fourth-generation ultra-wide bandgap materials, each wave of innovation has driven leapfrog development across communications, energy, computing, and other fields.
By analyzing the characteristics and generational replacement logic of four generations of semiconductor materials, we can infer the possible directions for fifth-generation semiconductors and discuss China's breakthrough path in this domain.
I. Characteristics of Four Generations of Semiconductor Materials and Generational Replacement Logic
First-Generation Semiconductors:
The "Foundational Era" of Silicon and Germanium
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Characteristics: Represented by elemental semiconductors like silicon (Si) and germanium (Ge), they offered advantages such as low cost, mature processing, and high reliability. However, they were limited by relatively narrow bandgaps (Si: 1.12 eV, Ge: 0.67 eV), resulting in poor voltage resistance and insufficient high-frequency performance.
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Applications: Integrated circuits, solar cells, low-voltage and low-frequency devices.
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Reason for Replacement: As the demand for high-frequency and high-temperature performance in communications and optoelectronics surged, silicon-based materials could no longer meet requirements.
Second-Generation Semiconductors:
The "Optoelectronic Revolution" of Compound Semiconductors
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Characteristics: Represented by III-V compound semiconductors such as gallium arsenide (GaAs) and indium phosphide (InP), these materials feature wider bandgaps (GaAs: 1.42 eV) and high electron mobility, making them suitable for high-frequency and optoelectronic applications.
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Applications: 5G RF devices, lasers, satellite communications.
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Challenges: Scarcity of materials (e.g., indium's abundance is only 0.001%) and high manufacturing costs, with toxic elements (such as arsenic) involved.
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Reason for Replacement: The emergence of new energy and high-voltage power equipment demanded even higher voltage resistance and efficiency, prompting the rise of wide bandgap materials.
Third-Generation Semiconductors:
The "Energy Revolution" of Wide Bandgap Materials
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Characteristics: Centered around silicon carbide (SiC) and gallium nitride (GaN), these materials offer significantly wider bandgaps (SiC: 3.2 eV, GaN: 3.4 eV), high breakdown electric fields, high thermal conductivity, and superior high-frequency performance.
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Applications: Electric drive systems in new energy vehicles, photovoltaic inverters, 5G base stations.
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Advantages: Compared to silicon-based devices, they reduce energy consumption by over 50% and shrink device volume by 70%.
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Reason for Replacement: Emerging fields such as artificial intelligence and quantum computing demanded materials with even higher performance, leading to the advent of ultra-wide bandgap materials.
Fourth-Generation Semiconductors:
The "Extreme Breakthrough" of Ultra-Wide Bandgap Materials
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Characteristics: Represented by
(Ga₂O₃) and diamond (C), these materials further extend the bandgap (Ga₂O₃: 4.8 eV), offering ultra-low conduction resistance, ultra-high voltage resistance, and significant cost-reduction potential.
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Applications: Ultra-high voltage power chips, deep UV detectors, quantum communication devices.
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Breakthroughs: Gallium oxide devices can withstand voltages exceeding 8000V, with efficiency tripling compared to SiC devices.
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Replacement Logic: As global demands for computing power and energy efficiency approach physical limits, new materials must achieve performance leaps at the quantum scale.
II. Trends for Fifth-Generation Semiconductors:
The "Future Blueprint" of Quantum Materials and Two-Dimensional Structures
If the evolutionary path of "expanding bandgap + functional integration" continues, fifth-generation semiconductors may focus on the following directions:
Topological Insulators:
Materials that are conductive on the surface but insulating inside, enabling the construction of zero-energy-loss electronic devices and overcoming the heat generation bottleneck of traditional semiconductors.
Two-Dimensional Materials:
Materials like graphene and molybdenum disulfide (MoS₂), whose atomic-level thickness enables ultra-high-frequency response and potential for flexible electronics.
Quantum Dots and Photonic Crystals:
Utilizing quantum confinement effects to regulate the energy band structure, achieving multifunctional integration of light, electricity, and heat.
Bio-Semiconductors:
Self-assembled materials based on DNA or proteins, compatible with both biological systems and electronic circuits.
Core Driving Forces:
Disruptive technological demands, such as artificial intelligence, brain-computer interfaces, and room-temperature superconductivity, are propelling semiconductors towards intelligent and bio-compatible evolution.
III. China's Opportunities:
From "Following" to "Running Side by Side"
Technological Breakthroughs and Industry Chain Deployment
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Third-Generation Semiconductors:
China has achieved mass production of 8-inch SiC substrates, with automotive-grade SiC MOSFETs successfully deployed by carmakers like BYD.
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Fourth-Generation Semiconductors:
Institutions like Xi'an University of Posts and Telecommunications and CETC 46 Institute have broken through 8-inch gallium oxide epitaxy technology, joining the ranks of the world's leading players.
Policy and Capital Support
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The national "14th Five-Year Plan" designates third-generation semiconductors as a key area.
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Local governments have set up industry funds worth hundreds of billions of yuan.
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In the 2024 Top 10 Technological Advances, achievements like 6–8 inch GaN devices and gallium oxide transistors were recognized, indicating full supply chain breakthroughs.
IV. Challenges and Pathways to Breakthrough
Technical Bottlenecks
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Material Preparation:
Large-diameter single crystal growth has low yield rates (e.g., gallium oxide is prone to cracking) and defect control is extremely challenging. -
Device Reliability:
Standards for lifetime testing under high-frequency and high-voltage conditions are not yet fully established, and automotive-grade certifications are lengthy.
Industry Chain Shortcomings
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Dependence on Imported High-End Equipment:
For instance, domestic production rates for SiC crystal growth furnaces are below 20%. -
Weak Application Ecosystem:
Downstream companies still prefer imported devices; domestic substitution will require policy guidance.
Strategic Development Approaches
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Industry-University-Research Collaboration:
Learn from models like the "Third-Generation Semiconductor Alliance," jointly tackling core technologies through collaboration between universities (such as Zhejiang University Ningbo Institute of Technology) and enterprises. -
Differentiated Competition:
Focus on incremental markets like new energy and quantum communications to avoid direct confrontation with traditional industry giants. -
Talent Cultivation:
Establish special funds to attract top scholars from overseas and promote the development of disciplines such as "Chip Science and Engineering."
From silicon to gallium oxide, the evolution of semiconductors is a saga of humanity challenging the limits of physics.
If China can seize the window of opportunity presented by fourth-generation semiconductors and strategically position itself for fifth-generation materials, it may achieve a "lane change overtaking" in the global technological race.
As Academician Yang Deren said, "True innovation requires the courage to tread untrodden paths."
On this road, the resonance of policy, capital, and technology will determine the future of China's semiconductor industry and its journey towards the stars and the sea.