All of the major packaged LED manufacturers were present at LightFair International (LFI), with Everlight Electronics, Samsung Electronics, Osram Opto Semiconductors, Luminus, and Cree all hosting demonstrations that point toward future LED trends. Apparently, broad adoption of chip-scale packages (CSP) will wait for next year, although high-density and –intensity package architectures will be very important in the shorter term, as will package architectures that deliver new beam distributions for solid-state lighting (SSL) applications.

Osram Opto Semiconductors

The packaged LED announcements and demonstrations at LFI were generally tuned to specific applications as is increasingly the case in the technology sector for LEDs that target general illumination. For example, Osram announced the new Duris S 2 mid-power LED designed for applications such as LED retrofit tubes for fluorescent replacement and for other shallow, ceiling-mount linear fixtures. The new LED measures 2×1.6 mm — the smallest packaged LED in the Duris family.

Osram uses what it calls a volumetric phosphor technology in manufacturing the Duris S 2. The phosphor is mixed into a three-dimensional silicone encapsulant atop an epoxy-molded-compound (EMC) package/substrate. The result is a packaged LED that emits from the four sides of the device as well as from the top surface, creating a wider beam pattern for the targeted application. Such an emission pattern enables more-shallow designs in linear luminaires designed for flush-mount or recessed mounting.

The night before the LFI exhibits opened, Samsung held a press conference and executive vice president Jacob Tarn also positioned CSP technology as a key enabler of further efficacy gains and ultimately lower system cost. Tarn was bold throughout his presentation, asserting that Samsung alone was capable of a number of packaged-LED innovations including gallium-nitride-on-silicon (GaN-on-Si) LEDs along with true CSP devices. About silicon substrates, Tarn said, “Samsung is the only company in the word to be capable of 8-in. GaN-on-Si,” and added that such devices will come in 2016, probably based on CSP technology.

Still, despite Tarn’s boasts on CSP, and the company’s long CSP experience in the broader semiconductor industry, he said volume production of sapphire-based CSP product would come late this year at the earliest. He said Samsung had already shipped CSP-based LEDs into display backlight application and claimed that by shipping late this year the company would be first to commercialize CSP LEDs for general illumination.

Tarn’s claims led us to ask him specifically about Lumileds. In the SIL keynote mentioned above, Lumileds’ senior vice president of research and development Jy Bhardwaj said the company shipped more than a quarter-billion CSP LEDs in 2014. Samsung’s Tarn argued, however, that the Lumileds products weren’t true CSP devices although he did not define what must be a subtle perceived difference. We will follow up on that difference of opinion.

Everlight Electronics

Meanwhile, Ewing Liu, head of lighting marketing at Everlight, took a slightly more rational approach when discussing the CSP sector. Everlight is truly a packaging specialist, buying LED chips from third parties such as Epistar. Liu said Everlight can deliver CSP LEDs today, but that few customers have the high-precision printed-circuit-board (PCB) manufacturing capability to use the LEDs. He said some auto makers can work with the LEDs, but Liu expects the general-lighting industry to delay uptake until at least 2016. Of course, Lumileds has asserted from day one that many lighting customers would buy CSP LEDs in so-called level-2 or modular light engine form with Lumileds assembling the PCBs.

Everlight showed a number of other recent LED developments at LFI. For example, the EAHE 5630 mid-power LED achieves 187 lm/W at 0.2W and is designed for linear applications such as LED T8 tubes. The EAHP 3030 mid-power LEDs can operate to 1W and are offered in CCT options as low as 2200K for halogen replacement. Everlight also has some impressive UV LEDs, although Liu said the company is still working to boost power output and lifetime on those LEDs.

<Source: LEDs Magazine>