We live in the era of professionalization – we are continually looking for solutions that would let us be more and more effective. That is why we decided to remake our cleanroom. Now it is a room of 45 m² with ten workstations.
The modern-day cleanroom was developed in the sixties of the 20th century by Willis Whitfield. It was a great deal – only within a few first years, this invention had generated more than US$50 billion in sales.
The cleanroom in a nutshell
In the cleanrooms, there are strictly specified conditions – the controlled concentration of contaminations guarantees the best (in this instance: the cleanest) production conditions. The cleanrooms are isolated from the surroundings by the proper infrastructure. Their dimensions are not defined – it can be a tiny room as well as a huge hall. The heart of every cleanroom is the air handlers that provide the proper air conditioning. They consist of HEPA or ULPA filters and other equipment like coolers, heaters or humidifiers.
There are a few procedures that facilitate the maintenance of cleanliness in the cleanrooms. The truth is that the greatest enemy of the cleanliness in such rooms is… human. Only the trained staff wearing protective clothing should have access to the cleanrooms. Furthermore, the equipment can affect the cleanliness of the cleanrooms – hence, all of the utensils should be made of materials that minimize the generation of airborne particles.
It is also necessary to constantly monitor the critical parameters of the cleanrooms, not only the cleanliness but also temperature, humidity, or pressure.
How clean are cleanrooms?
The cleanrooms are classified according to the permitted number of airborne particles in a particular volume of air – per one cubic meter (m3) or one cubic foot (ft3).
The most commonly used classification of cleanrooms is the ISO standard 14644-1. In the table*, you can find the maximum concentrations of particles in a different size per cubic meter in all of the ISO classes:
|ISO 3||1 000||237||102||35||8||–|
|ISO 4||10 000||2 370||1 020||352||83||–|
|ISO 5||100 000||23 700||10 200||3 520||832||29|
|ISO 6||1 000 000||237 000||102 000||35 200||8 320||293|
|ISO 7||–||–||–||352 000||83 200||2 930|
|ISO 8||–||–||–||3 520 000||832 000||29 300|
|ISO 9||–||–||–||35 200 000||8 320 000||293 000|
In our offices, the maximum concentrations of particles in the size of ≥0.5µm is about 35 000 000/m3. Then, they classify as the ISO class 9.
There are also other classifications of cleanrooms such as the Federal Standard 209 (FED STD 209/FS 209), an American federal standard that was officially canceled but is still widely used. In the Federal Standard 209, there are six classes – 1, 10, 100, 1 000, 10 000, 100 000. Each class designation describes the number of particles in size of ≥0.5µm per one cubic foot of air. In other words, in class 1, there can be at least one particle in size of ≥0.5µm in one cubic foot of air, etc. Each class of the Federal Standard 209 compares with a specified class of the ISO standard 14644-1, here you go: FS 209 class 1 (ISO class 3), FS 209 class 10 (ISO class 4), FS 209 class 100 (ISO class 5), FS 209 class 1 000 (ISO class 6), FS 209 class 10 000 (ISO class 7), and FS 209 class 100 000 (ISO class 8).
It is worth noticing that cleanrooms are not sterile – they won’t protect us against microorganisms.
The new level of production
Some industries must use cleanrooms – e.g., food and drink, pharmaceutical, or biotechnology. They are also required in a few sectors of the electronic industry (e.g., semiconductors).
Our cleanroom fulfills the requirements of the ISO class 6 (or FS 209 class 1 000). That enables us to increase the scope and quality of Unisystem’s production, e.g., the integration of displays with touch panels with the air bonding method (optical bonding technology will be available soon). Such activities can only be done in the cleanrooms – if there are any contaminations between some “layer” of the module, the final device might not function properly. What is more, we can also integrate your display with, e.g., glass that prevents mechanical damages or with coatings as anti-reflective (AR) or anti-fingerprints (AF).
In fact, sometimes the customers appreciate the ability to produce in our cleanroom when they face problems with commodities provided by foreign suppliers, e.g., from China. The customer complaints are prolonging due to, e.g., shipments. The carrying time from Poland to China in case of non-special deliveries may take up to 10 days. In such cases, we can manage in a flash – that is our great advantage.RADOSŁAW PYTER
Key Account Manager
What is more, our Department of Quality supervises all of the production processes. Every manufactured module is full optical inspected due to our restrictive internal procedures.
Contact us to find out the lead time for the manufacturing of your device.
Optical Bonding – How to Combine Display with a Touch Panel
The touchscreen function is increasingly becoming a common display feature in industry. It is an additional feature because specific components need to be attached to the standard display to make …
Optical Bonding – How to Combine Display with a Touch Panel Read More »
Implementing Touch Screens in Public Spaces
When using devices located in public spaces, we increasingly interact with them through touch screens. We operate in this manner devices such as ATMs, ticket machines, parking meters, parcel machines, …
Local Dimming – improving LCDs
Backlight in LCDs directly affects parameters in the end user’s application. There are two types of backlight available nowadays: edge-lit and direct-lit. Backlights can be further improved in their performance …
LCD-TFTs – in pursuit of non-standard shapes
Most of the LCD-TFTs surrounding us are rectangles in standard 16:9 aspect ratio. We are familiar with this common format. It works well for most applications. In recent years, however, …