The semiconductor manufacturing industry is rapidly evolving and attracting significant attention from businesses. One crucial and indispensable component for success in chip production is the cleanroom. Let’s explore the role of cleanrooms in chip manufacturing and reputable cleanroom construction companies with INTECH Group in the following article.
The Role of Cleanrooms in Chip Manufacturing
Cleanrooms play a vital role in the process of chip and other small electronic device manufacturing. The primary roles of cleanrooms in chip production include:
Preventing dust and particulate matter: Electronic chips are predominantly made from thin and small layers, where tiny dust particles can cause discrepancies in the manufacturing process. A patch of dust or small particles can damage printed circuits and may harm small components on the chip’s surface. Cleanrooms are designed to remove dust and particles from the air inside, preventing them from infiltrating the production process.
Temperature and humidity control: Maintaining stability in temperature and humidity within cleanrooms helps sustain ideal conditions for the manufacturing process, minimizing the rate of defective products. Any fluctuations in environmental conditions can affect the performance and stability of the manufactured electronic chips.
Ensuring quality and performance: By eliminating disruptive factors like dust and particles, cleanrooms enhance the quality and performance of the produced chips. This is particularly important in manufacturing electronic components with increasingly smaller sizes and high precision requirements.
Standards Applied in Chip Manufacturing Cleanrooms
Cleanrooms for chip manufacturing typically require a highly clean environment to prevent contaminants that could disrupt the semiconductor manufacturing process. Federal Standard 209E (FED-STD-209E) (1992) and ISO 14644-1 are two standards commonly applied in chip manufacturing cleanrooms.
Federal Standard 209
This standard was first defined in 1963 (referred to as 209), and then continuously improved, evolving into versions like 209A (1966), 209B (1973), and eventually 209E (1992).
FED STD 209E defines cleanroom classes based on the quantity of dust particles and contaminants present in the air per standard unit (cubic meters or cubic feet). Cleanroom classes are determined by measuring and evaluating the quantity of dust particles and contaminants in the air with pre-defined particle sizes, according to the logarithmic scale of dust particle diameter larger than 0.5 μm.
ISO 14644-1 Standard
ISO 14644-1 standard, released in 1999, is commonly used to classify cleanrooms based on the permissible quantity of dust particles and contaminants in the air. These standards classify cleanroom ISO classes based on the expression: Cn=10N[0.1D]2.08
Where:
- Cn: maximum permissible concentration (in particles/m3) of airborne particulate matter greater than or equal to the considered size
- N: ISO cleanliness classification number, not exceeding 9 and the minimum allowable number being 0.1
- D: particle diameter measured in micrometers. Here, 0.1 is a constant with an exponent of μm
Thus, the dust concentration can be determined from the above formula, facilitating the classification of cleanliness levels based on the limit table.
Equivalent standards stipulated in Vietnam include TCVN 8664-1:2011 for cleanliness classification.
For chip manufacturing, cleanrooms typically have to meet very high standards:
- ISO 1 or ISO 2: These are the highest cleanliness levels according to ISO 14644-1 standards. In these cleanrooms, the number of particles is extremely controlled. For some chip manufacturing processes, especially for nano-sized chips, ISO 1 cleanrooms are often required.
- ISO 3 or ISO 4: Other chip manufacturing processes may effectively operate in ISO 3 or ISO 4 cleanrooms.
The specific level required depends on the type of chip being produced and the technology used. Manufacturing components with nano-sized dimensions and surfaces containing many tiny features require a cleaner environment compared to larger and less complex components. Chip manufacturing companies often invest heavily in cleanroom systems to ensure their products meet stringent quality requirements.
Important Criteria in the Design and Construction of Semiconductor Cleanrooms
Climate Requirements (Temperature, Humidity, Pressure)
The average temperature in semiconductor cleanrooms typically ranges from 20 to 26 degrees Celsius, providing a safe temperature for equipment and stable operation of electronic components, preventing solder joints or bonds from melting.
Average humidity in semiconductor cleanrooms ranges from 18 to 55%, depending on the type of component and the presence of personnel. Each manufacturing plant will have regulations regarding temperature and humidity.
Pressure differentials in semiconductor cleanrooms typically range from 15 to 45 Pa, with most cleanrooms operating at positive pressure to limit contamination from outside.
Noise Requirement
Noise levels (in the empty state) in semiconductor cleanrooms usually range from 40 to 65 dB and must not exceed 65 dB.
Equipment and Materials Requirements
Requirements for cleanroom equipment, materials, surface coatings (electrostatic paint, antibacterial floor paint), fire resistance (mineral wool panels, PU, PIR), design, and movement should also be ensured to suit the manufacturing environment and investment limits.
Fresh Air Flow Requirements
The amount of fresh air in semiconductor manufacturing plants must meet two main objectives: compensating for the total exhaust air volume in the plant and providing the necessary clean air to maintain positive pressure in the cleanroom.
Ensuring a minimum air cleanliness per person per hour in electronic cleanrooms of 40m3.
Other Requirements
Appropriate lighting, humidity, and temperature for workers, especially areas such as photolithography, which require suitable lighting as optical materials are very sensitive to white light and UV light.
Water and compressed air supplied into certain stages must be absolutely pure.
Exhaust gas and wastewater require quality treatment systems as they may contain optical materials, HF, etc., with HF being a highly toxic substance.
Cleanroom requirements for semiconductor manufacturing also demand extreme attention to electrostatics, so when constructing, it is essential to ensure factors related to electrostatics.
INTECH Group – Specialized Consultant, Design, Turnkey Construction of Semiconductor Cleanrooms
One of the contributing factors to the success of semiconductor manufacturing businesses is choosing a reputable and professional cleanroom construction company. INTECH Group confidently delivers professional value and satisfaction to customers by providing comprehensive services from consulting, designing to constructing cleanrooms. INTECH has implemented projects for numerous customers and investors from Japan, Korea, the US, Europe, Indonesia, Thailand, Vietnam, and more.
Contact INTECH Group now to receive advice from experienced and professional experts in the field of electronic and semiconductor cleanrooms.
