Chip carriers are common building blocks used in semiconductor packaging to hold the IC and offer electrical connectivity through which the IC is connected.
Semiconductor industry requires clean surfaces of devices due to multiple reasons. Organic impurities like oils, residues, and particles are the main type of contamination which is an obstacle in the adhesion and the reliability of the device.
Plasma is a fast, efficient, and non-consuming procedure for the removal of extraneous contaminated particles and thus ensuring the right level of cleanliness.
Understanding Chip Carriers and Their Applications
What are Chip Carriers?
Chip carriers are customized substrates on which an integrated circuit (IC) is placed and protected. They primarily guarantee the thermal and electrical stability of the semiconductor devices they hold.
These carriers work as the link between the small semiconductor chips and the electronic systems.
Types of Chip Carriers
There are a few types of chip carriers that are most commonly used in the industry:
- Ceramic chip carriers are fine with thermal properties and stability.
- Organic chip carriers are the best solution for many applications and the most affordable ones.
- Metal-core substrates are needed for high-power applications, which provide superior heat dissipation.
- The different types of chip carriers, such as processors, sensors, and other high-performance devices, are mainly used in earlier high-performance stages.
Applications
Chip carriers are used in many different electronic devices; here are a few examples:
- Microprocessors in computers and smartphones
- Memory modules in different electronic devices
- Automobile sensors for vehicle monitoring and safety systems
- Devices as a part of the telecommunications infrastructure
Challenges with Organic Contaminants
Sources of Contaminants
Any organic contaminants on chip carriers can stem from various locations during the making process. Oils and flux residues are some of the familiar contaminants that can originate from:
- Oils from handling or machining processes
- Flux residues from soldering operations
- Solder paste remnants
- Adhesive residues from temporary bonding or masking
Impact on Chip Carrier Performance
The presence of organic contaminants might lead to various adverse effects on chip carrier performance:
- Less adhesion in the die results in more possibility of device failure.
- Signal issues due to less electrical conductivity. Therefore, the device may not function properly.
- Higher failure rates because of lower thermal or electrical performance
Limitations of Traditional Cleaning Methods
Whereas traditional cleaning methods using chemical solvents have made strides, there are disadvantages:
- The chemical solvents can leave their residues in the place of the contaminants.
- Harsh chemicals may cause damage to the components and/or surface finishes due to their presence near these delicate materials.
- Environmental concerns related to using and disturbing these chemicals
How Plasma Cleaning Removes Organic Contaminants
What is Plasma Cleaning?
Plasma cleaning is a method in which ionized gases are used to clean surfaces at the molecular level. In this method, a plasma is forced to exist under very high pressures, which are taken up by the electrons and the gas molecules.
These plasmas encounter the obstacles on the surfaces, break them, and throw them away through the chip carriers at high speed, thus leaving the surface clean.
Mechanism of Cleaning
The cleaning process in the plasma treatment includes the following steps:
Creation of reactive species: The plasma generates reactive species such as oxygen radicals.
Interaction with contaminants: The reactive species bind with organic pollutants on the surface.
Molecular bond disintegration: The incoming particles break the organic molecules into more minor, volatile compounds.
Byproduct removal: The resulting volatile compounds are quite easily removed from the surface, which eventually affects its cleanliness.
Advantages of Chip Carriers
Plasma treatment technology, with its chip-specific advantages (e.g., chip-carrier-mounted vibration measurement), provides several benefits:
- It does not involve abrasive materials and direct or significant contact with the fragile structures of carriers (which may be damaged).
- It eliminates the microscopic amounts of organic dust left by the preceding cleaning procedures.
- It cleans the carrier surfaces evenly, even with complex geometries and recessed areas.
Benefits of Plasma Cleaning for Chip Carriers
Enhanced Surface Cleanliness
Plasma cleaning provides clear, ultra-clean surfaces and conducting substances for bonding, coating, or soldering. This purity is what makes the final product desirable and reliable.
Improved Adhesion
Plasma treatment thoroughly cleans the surface and removes the dirt particles, which was the main reason for the weak and unreliable attachment of integrated circuits, wires, or encapsulants.
This change in the substrate material provides a much better connection to the device, thus maintaining the overall integrity of the packaged device.
Better Electrical Performance
Plasma cleaning dissolves the contaminants that could have interfered with the electrical connection between the components. Hence, its benefit is better signal integrity from the assembly of chip carriers.
Eco-Friendly
Plasma cleaning reduces the use of chemical solvents, which positively affects the environmental treatment of the cleaning activity. This complies with the expanding ecological consciousness among the semiconductor industry players.
Cost-Efficient
One typical case is that the outlay for plasma cleaning equipment is a bit high, but most of the time, it reduces defects and reworking on the production floor. This usually results in significant time and financial savings in the long term.
Applications of Plasma-Cleaned Chip Carriers
Die Bonding
Plasma cleaning would guarantee the bond of the integrated circuits to the carrier surface without any defect, thus a device that has proper performance as well as product reliability would be assured.
Wire Bonding
Clean surfaces increase the wire’s adhesion to bond pads. Thus, electrical connections are made easier, and the speed increases.
Encapsulation
The plasma process enhances the adhesion of the coatings or encapsulants, resulting in better durability and resistance to weather conditions.
Thermal Management
Clean surfaces form the bonds of the thermal pads and adhesives, which assist heat dissipation in high-power devices.
Process Optimization for Plasma Cleaning
Key Parameters
Before the plasma cleaning of the chip carriers, it is important to set several parameters:
Gas Composition: The selection of gas (for example, oxygen or inert gas mix) would depend on the type and criticality of the contaminants to be removed.
Power Levels: The plasma is the control parameter that has to be set in accordance with the optimum level of the cleaning power that does not cause any harm to the delicate carrier parts.
Treatment Duration: The exposure time is a critical period that should be fine-tuned to guarantee the complete removal of contaminants without overprocessing.
Integration into Production Lines
State-of-the-art plasma cleaning systems are being integrated into semiconductor manufacturing entities. This technology, which is one part of the integration, provides high-speed operations and ensures the quality of cleaning throughout the entire process.
Challenges and Considerations
Material Compatibility
It is of utmost importance that the plasma cleaning settings are correct for the specific chip carrier type, whether ceramic, organic, or metal-core. To make the cleaning as effective as possible, one might need to control the parameters for different materials.
Over-Treatment Risks
Care must be taken to prevent over-processing, which could change the equipment’s surface properties or damage the components due to the high treatment. Maintenance of proper process control and monitoring are inevitable measures against these risks.
Cost of Implementation
While plasma cleaning has inevitable benefits, the equipment and training costs may be too much to accept.
Companies have to take into account this expense together with the more than fair results guaranteed by plasma cleaning, such as an increase in production power and product quality.
Case Studies and Industry Insights
Semiconductor Packaging
In one instance, a flagship semiconductor packaging factory used plasma cleaning to remove residues from the chip carriers, which reduced side effects. It also brought down die-leveling reproduction by 15%, with models of the products.
Automotive Electronics
An automotive electronics manufacturer used innovative coatings and materials fabrication technologies to produce plasma-treated chip carriers for applications like engine controllers.
The synthesized compounds yielded a beneficial increase of 20% in the module’s lifetime for the temperature and vibration situations it underwent.
5G Communication Devices
In the 5G communication devices, plasma treatment of the chip carriers provided better conditions for soldering and wire bonding, thus they had to be placed in a device that passes data constantly.
This condition caused an increase in the signal by 30% and a reduction of the noise during the calling handover process for the assembled devices.
Future Trends in Plasma Cleaning for Chip Carriers
Advanced Contaminant Removal
Scientists’ research drives the production of plasma systems that could remove organic and inorganic contaminants in one operation. Such an improvement reduces the time spent cleaning operations even more, thus saving the semiconductor industry time and money.
AI-Driven Plasma Processes
The fusion of artificial intelligence for real-time monitoring of plasma parameters and tuning up plasma power has come to light.
This might pave the way for the precise and adaptive cleaning process, which will only increase the efficiency and overall effectiveness of plasma cleaning for chip carriers.
Sustainability
The semiconductor industry now offers various green technologies and processes to reduce risks.
This includes creating advanced plasma sectors, building energy-efficient plasma systems, and using more environmentally friendly process gases.
Conclusion
Plasma cleaning is a powerful and flexible way to clean off organic contaminants from chip carriers in the semiconductor industry.
The increasing demand for multifunctional and micro electronic devices will make plasma cleaning essential in quality provision. Fari Plasma is doing quality work by erasing the organic contamination on the chip carriers through plasma cleaning.
As the technology develops, it is expected to become an essential part of the semiconductor industry and significantly impact the future generation of electronic devices.
