What are MicroLED 바카라 꽁머니 사이트s?

바카라 꽁머니 사이트s (µLEDs) are a relatively new technology that produces brilliant, high-resolution바카라 꽁머니 사이트sthat can be economically scaled up to huge dimensions – easily more than 20 feet (6 meters).  Right now, they’re useful for large 바카라 꽁머니 사이트s in conference rooms, arenas, concert venues, and outdoor applications. Eventually, they will probably become a common technology for big TVs. In the next five years, µLED 바카라 꽁머니 사이트s will grow to be a B-plus market — and lasers play a critical role in enabling their production.

The difference between AMOLED and 바카라 꽁머니 사이트s

With AMOLED and other 바카라 꽁머니 사이트 technologies currently used for mobile devices and televisions, the light emitting (or light filtering) pixels are produced directly on the glass panel that forms the 바카라 꽁머니 사이트. So, scaling them up in size means performing multiple steps with expensive OLED materials on a very large panel containing all the necessary circuitry. That gets expensive and impractical very fast as you go larger. It’s why televisions larger than 80 inches can cost tens of thousands of dollars.

MicroLED 바카라 꽁머니 사이트s are different. The individual LED emitters are mass-produced on relatively small sapphire wafers. They are packed closely together resulting in low unit costs. These µLEDs are then removed from that wafer and transferred to a piece of glass with a circuit already patterned on it.  Really huge 바카라 꽁머니 사이트s can be cost-effectively constructed by increasing the spacing between the µLEDs on it – the main cost driver is then the number of pixels, not the size of the glass. Tiling together many individual panels also keeps costs down for larger 바카라 꽁머니 사이트s.

바카라 꽁머니 사이트llions and 바카라 꽁머니 사이트llions of pixels

Now, there’s one big hitch. Each pixel in the µ바카라 꽁머니 사이트바카라 꽁머니 사이트consists of three separate LED emitters (red, green, and blue) which are really, really small. State-of-the-art is currently about 50 x 50 microns and is predicted to eventually approach 10 x 10 microns. And, there are literally millions of them. For example, even just a standard high-definition 바카라 꽁머니 사이트 (1920 x 1080) has over 2 million pixels. And, remember, each one of these pixels requires three separate µLEDs.  So, a really large 바카라 꽁머니 사이트 might have 100s of millions of µLEDs in it.

The manufacturing challenge is to physically move all these tiny LED sources from the sapphire they’re grown on to the final glass 바카라 꽁머니 사이트 panel. And, to place them very precisely, and not to damage them. Any kind of mechanical method, whether it uses vacuum pickup or very precise actuators, would be too slow, and probably too rough, for handling the µLEDs. It should be no surprise that lasers supply exactly the “light touch” necessary for such a delicate and demanding operation.

What Is 바카라 꽁머니 사이트-Induced Forward Transfer (LIFT)? Thanks for asking.

The practical method turns out to be a process cal바카라 꽁머니 사이트 Laser-Induced Forward Transfer (LIFT). How does it work? You can see it illustrated in . In brief, it’s a two-stage process. First, the µ바카라 꽁머니 사이트s are separated from the sapphire wafer they’re grown on and transferred to a temporary carrier using another laser-based technique cal바카라 꽁머니 사이트 Laser Lift-Off (LLO). This leaves the µ바카라 꽁머니 사이트s on the temporary carrier with the same close spacing they had on the growth wafer.

Figure. In LIFT a large area laser beam passes through a photomask so that only specific dies are released and pushed onto the 바카라 꽁머니 사이트 substrate. A uniform so-called top-hat beam is critical to perfect placement. (Not to scale).

Next comes LIFT. Here, pulses from anultraviolet (excimer) 바카라 꽁머니 사이트enter through the backside of the carrier, which is transparent. The laser light is absorbed in the thin layer of adhesive which has been holding the µLEDs to the temporary carrier and vaporizes it. This actually physically blows the µLEDs off and pushes them onto the final 바카라 꽁머니 사이트 panel, which is placed in close contact. Adhesive on the final glass panel holds the µLEDs in place.

The beam and the mask

The secret is this, though. The rectangular laser beam passes through a mask that has holes in it that are the same distance apart as the pixels in the final 바카라 꽁머니 사이트. So only every 5th, or even every 10th, µLED is pushed across to the 바카라 꽁머니 사이트 by a given laser pulse. The optical path with the mask is fixed and the temporary carrier then moved over very slightly to get to the adjacent set of µLEDs, but the 바카라 꽁머니 사이트 panel is moved a large distance, and the process is repeated on a new part of the panel. This allows a large number of µLEDs to be economically fabricated on a relatively small sapphire wafer and then placed with much larger separations to create a single big panel. And, the other big advantage of LIFT is that it’s fast. Thousands of µLEDs are moved by each pulse. At a laser pulse rate of 500 pulses/second (500 Hz), an area up to 32 mm x 1 meter can be covered in µLEDs in only a second!

We’re working on it

Coherent is already producing a tool cal바카라 꽁머니 사이트UVtransferfor µLED 바카라 꽁머니 사이트 processing that actually performs three separate processes – Laser Lift-Off (LLO), Laser-induced Forward Transfer (LIFT), and Repair/Trimming for defective pixels. This 3-in1 tool will set processing standards and demonstrates the potential of manufacturing large µLED 바카라 꽁머니 사이트s practical and economical.