Technological breakthrough: LED chip anti-reverse electrostatic capacity up to 3 kV

[OFweek Semiconductor Lighting Network Editor/mike Translation/oscar] Korean researchers have improved the anti-back-electrostatic ability of InGaN LEDs to 3 kV by integrating bypass diodes in LED chips . Researchers from the Korea Optical Technology Institute (KOPTI) and the Gwangju Science and Technology Institute claimed: "This LED chip is easy to process and has high reliability."

Researchers have been trying to improve the current anti-reverse electrostatic capability of 100V-1kV . The recovery of positive static electricity has decreased in the range of 1 kV to 3 kV . Such devices are often used in traffic lights, large-scale displays, and liquid crystal display backlights.

The difference in characteristics between forward bias and reverse bias is due to the high dislocation density difference between the epitaxial material and the side device structure. Side devices are required for standard nitrided LEDs grown in an insulating sapphire substrate . These two opposite characteristics tend to cause a large number of reverse ESD voltage pulses and damage the LEDs .

Researchers have employed a number of methods to avoid such damage to the device by reducing the density of defects comprise ---, external diodes. However, it is difficult to apply these technologies to real production processes at low cost.

The researchers used a traditional In 0.15 Ga 0.85 N/GaN MQW 450nm (blue) LED architecture to grow in c-plane sapphire in MOCVD equipment . This LED is etched to the n -type epitaxial growth layer by photolithography and ICP . The indium tin oxide ( ITO ) LED chip is equivalent to a transparent ohmic electrode, and the bonding pad is composed of a gold-nickel-chromium-tin alloy.

The researchers extended the bypass diode to the LED by extending the n- pole contact to the p- region (see Figure 1 ) to achieve ESD protection of the LED chip . Treatment with oxygen plasma between the n- pole and p-GaN causes the Schottky barrier to rise; the purpose of this is to reduce the reverse leakage current generated by the reverse ESD . Because large leakage currents tend to damage the n poles, the performance of the device is reduced.

Figure 1 : ( a ) cross-sectional view and circuit schematic of the amplified n- pole LED ; top view ( b ) conventional ( LED-C ), comb-shaped LED-F3 without n- pole and LED-F5 , ( c ) plasma treated Comb ( LED-F3-P and LED-F5-P ). The shaded area in ( c ) is the plasma processing area.

Professional Iron Lamp manufacturer is located in China, including Iron Pendant Lamp,Iron Pendant Light,Metal Pendant Light, etc.

Iron Pendant Lamp

Iron Lamp,Iron Pendant Lamp,Iron Pendant Light,Metal Pendant Light

Monike lighting , https://www.monikelight.com