A semiconductor manufacturer faced challenges cleaning intricate structures on substrates. Conventional methods were inadequate, causing defects and lower device performance. Cee® suggested using megasonic technology, utilizing high-frequency sound waves to remove contaminants effectively. We chose the ProSys Stainless Steel MegPie™ transducer for its precision and adaptability, integrated with DataStream Software for process control. The solution led to reduced cleaning time, improved yield, and less structural damage.
A semiconductor manufacturing company was facing significant challenges in cleaning high aspect ratio structures and hard-to-clean materials on their substrates. Traditional cleaning methods, such as chemical cleaning and spin cleaning, were proving insufficient to remove stubborn contaminants and residues from deep trenches, narrow channels, and complex surface geometries. As a result, the company was experiencing reduced yield, increased defects, and decreased overall device performance. They needed an advanced cleaning solution that could effectively and safely clean high aspect ratio features without causing damage to the delicate structures.
After careful evaluation of the customer’s challenges including substrate sizes, aspect ratio, device sensitivity, materials, throughput, and operator requirements, Cee® recommended megasonic technology for advanced cleaning capabilities.
The megasonic approach utilizes high-frequency acoustic energy (0.8-2 MHz) to create cavitation bubbles in the cleaning solution. These bubbles collapse near the surface of the substrate, generating powerful micro-energy that effectively removes particles and contaminants.
Because the acoustic transducer requires the presence of liquid material on a spinning substrate, the Apogee® 450 Developer was selected as the ideal base model.
After an extensive evaluation of different megasonic cleaning systems, Cee® selected the ProSys Stainless Steel MegPie™ as the transducer most appropriate for the client’s use case.
Transducer Selection: The ProSys Stainless Steel MegPie™ offered chemical compatibility and precision control over frequency and power output. This allowed the client to adjust cleaning parameters for different materials and substrate sizes ensuring optimal cleaning performance.
Software Interface for Process Monitoring and Feedback: Megasonic controls were incorporated into DataStream Software, enabling complete recipe management to automate the cleaning process. Recipe options allowed for precise control over duty cycle, timing, and process power. Forward and reflective power values were captured in application logs for additional process optimization.
Fully Integrated for Process Flexibility: The megasonic transducer was affixed to a programmable positional arm allowing for adjustments to both radial position and z-axis. The radial positioning allowed the apparatus to serve for both conventional spin-cleaning/developing procedures and the acoustic cavitation of substrates. The recipe-controlled z-axis allowed for fine-tuning of reflective power and varying substrate thicknesses.
The megasonic process module was then packaged into an X-Pro II Workstation for consolidation of connection points, fume management, chemical storage, and ease of installation.
The client achieved measureable improvements including significantly reduced clean time, accelerated throughput, improved yield, and a reduction in damage to structures.
Substrate Sizes
60mm х 48mm
30mm x 24mm
100 x 0.145-0.2mm Germanium CMP polished wafers
200 x 0.7-0.9mm Germanium CMP polished wafers
PhotoMask
4″ square
5″ square
Materials
Isopropanol Alcohol (IPA)
H2O2:NH3
DI Water
N2
© Copyright 2024 - Cost Effective Equipment, LLC
Cee® is a registered trademark of Cost Effective Equipment, LLC.