Microwave-Assisted Processing for Advanced Semiconductor Nodes

• Volumetric Heating: Unlike surface-limited conduction, microwaves interact directly with dipolar species and free carriers. This enables uniform energy deposition deep within the wafer bulk, ensuring consistent and reliable processing.
• Selective Absorption: Materials with high dielectric loss, such as doped silicon and IGZO, absorb microwave energy preferentially. This allows for selective heating, which dramatically reduces thermal stress on sensitive materials like low-k dielectrics and polymer substrates.
• Rapid Thermal Cycles: MAP achieves dopant activation in under 60 seconds and at temperatures lower than traditional rapid thermal processing (RTP). This minimizes dopant diffusion and junction smearing, which is critical for forming ultra-shallow junctions.

• Dopant Activation Beyond Solubility Limits: MAP enables high phosphorus activation in silicon without extended diffusion, a key requirement for ultra-shallow junctions.
• Silicide Formation: Localized heating allows for precise phase transformation (e.g., NiSi → NiSi₂) with minimal agglomeration, preserving material integrity.
• Oxide Semiconductor TFTs: MAP facilitates low-temperature crystallization of IGZO, enabling the fabrication of flexible and transparent electronics.
• Microwave Plasma Cleaning: Provides effective wafer conditioning with significantly reduced ion bombardment damage, preserving delicate structures.

Successful MAP implementation requires addressing specific challenges to ensure high-volume manufacturing:

• Process Uniformity: Managing standing wave patterns in multimode cavities requires advanced impedance matching algorithms to ensure consistent heating across the entire wafer.
• Metrology: Implementing real-time dielectric loss monitoring and temperature mapping is crucial for closed-loop control and process repeatability.
• Tool Design: Creating integrated systems that combine microwave applicators with conventional heaters and thermal management is necessary for precise thermal gradient management.

MKS provides the unique domain expertise and integrated solutions necessary to overcome the toughest MAP challenges.

• Precision Power Delivery: Our industry-leading microwave generators ensure a uniform field distribution across the wafer, which is fundamental to process consistency.
• Advanced Integration: Proprietary, real-time feedback systems enable closed-loop control of dielectric loss and temperature, ensuring reliable and repeatable processing.
• Process + Equipment Synergy: MKS combines microwave applicators with thermal management and plasma technologies, delivering integrated systems optimized for demanding BEOL and 3D IC flows.
• Global Ecosystem & Support: A proven track record in semiconductor fabs worldwide ensures scalability, reliability, and support for high-volume manufacturing.

MAP-enabled modules are set to become standard in back-end-of-line (BEOL) and 3D integration flows, particularly for applications requiring:

• Monolithic 3D ICs: Critical for processes where thermal budgets below 400 °C are mandatory.
• Advanced Packaging: Ideal for processes involving polymer substrates and heterogeneous stacks.
• Energy-Efficient Fabs: Leveraging MAP’s low power consumption and rapid thermal cycles to optimize overall fab efficiency.

Learn More:

• MKS offers compact industrial microwave generators and systems in 915MHz and 2450MHz that are adaptable to a wide range of applications. See our Microwave Generators and Systems here
• Contact an MKS Applications Specialist to discuss how MKS Microwave Systems can improve your process.