Indium Blog

Miniaturization in LED Technology: MicroLEDs

  • LED Solder

  • Hi All,

    I recently spoke about Mini-LEDs and how Indium Corporation is meeting the assembly needs of that product in a recent post. Something that I had to do a fair bit of research on as a young person new to the electronics assembly field is the difference between Mini-LEDs and Micro-LEDs. While the names of each of those technologies imply the same thing (small LED), each of their design and application is fundamentally different from each other.

    I’ll start with a quick Mini-LED review. Mini-LEDs are commonly used in conjunction with LCD displays to emit light. The differentiator between Mini-LEDs and the current state-of-the-art Organic LEDs (OLEDs) are that Mini-LED systems are brighter, offer better contrast, and are cheaper, without running the risk of burn-out over time.

    The key point to make when comparing Mini-LEDs to Micro-LEDs are the kind of light it provides when used in a display. Mini-LEDs are used as a backlight in combination with an LCD to provide an image. Micro-LEDs, on the other hand, are used as the screen technology itself, with each individual LED being self-illuminating to provide a picture without the need for a backlight. The benefits of this technology are that Micro-LEDs can provide even brighter displays with better contrast than Mini-LED displays, and can be more efficient as well. The big downside with Micro-LEDs are that they are EXPENSIVE. This is due to the technology; Micro-LED pixel groups are modular, meaning the screens have to be large (Samsung’s smallest Micro-LED TV is 77 inches for example, and that’s on the small end) to avoid low resolution. Samsung’s 110-inch Micro-LED TV will cost roughly $150,000. My TV is only 45 inches, so that’s the kind of size and money we’re dealing with. Samsung also released its newest version of “The Wall” earlier in July, which uses Micro-LED technology, designed for retail environment displays.

    From an assembly standpoint, there isn’t as much differentiation for assembling Mini-LEDs vs Micro-LEDs. The solder paste used still needs to have excellent printability for the small component size of these technologies and the paste needs to have high tackiness to avoid die shift and minimal voiding to ensure strong joints. The necessary fluxes need to have high tackiness as well, and in some cases have a high enough activity to solder to surfaces like AuSn. The same assembly materials can be used interchangeably for both Mini-LEDs and Micro-LEDs.

    Mini-LEDs and Micro-LEDs are fascinating technologies, and Indium Corporation is prepared to meet their assembly challenges.