led driver in LED Lighting Industry

Semiconductor lighting source (here mainly refers to the G24 LED light source) now has quantities into the lighting field, but still a lot of problems, mainly energy efficiency, reliability, quality of light and color, as well as cost. About the content involved in energy efficiency and the quality of light and color is very rich, such as visual comfort, intelligent dimming control, we will not describe this. This article will discuss the major technical issues need to be resolved, attributed to the “three high and one low, high light efficiency, high color rendering, high reliability and low cost technical problems, and achieve low-cost essentially technical problems led driver. Solve the four major technical problems, need to take a series of measures in the semiconductor lighting industry chain, such as the adoption of new technologies, new structures, new processes, new materials, only mentioned here should take the technical route and direction, we want to product innovation in the LED business help.

How to achieve high light efficiency

led driver in LED Lighting Industry

Semiconductor lighting light efficiency, or energy efficiency is an important indicator of the energy-saving effect. LED device luminous efficiency the industrialization levels up to 120 ~ 140lm / W, and made the overall energy efficiency of the lighting can be more than 100lm / W. This is not high, the energy-saving effect is not obvious value of 250lm / W there is a great distance away from the theory of optical efficiency of semiconductor devices. To achieve true high light efficiency, related to all aspects of the industry chain to solve the technical problems, mainly to improve the internal quantum efficiency, external quantum efficiency, encapsulated optical efficiency and luminaire efficiency, epitaxy, chip, package, lamps several a link to solve the technical problems.

1. Improve the internal quantum efficiency and external quantum efficiency

Take the following measures to improve the internal quantum efficiency and external quantum efficiency.

(1) surface roughening, and the non-polar substrate

 

Using nanometer FIG type substrate, the alignment type the FIG type substrate or non-polar, semi-polar substrates growth GaN reduce dislocation and defect density and polarity field influence, improve internal quantum efficiency led driver.

(2) generalized homogeneous substrate

Using HVPE (hydride Liquid Phase Epitaxy) grown on the sapphire substrate Al2O3 GaN, as a mixed homogeneous substrate GaN/Al2O3 of, based on this epitaxial growth of GaN-, can greatly reduce the dislocation density of 106 to 107cm-2, and greatly improve the internal quantum efficiency. Nichia, Cree and China, Peking University in research and development.

(3) improvement of the quantum well structure

Control the patterns of change and the change amount of the In composition, to optimize the quantum well structure is to improve the electron and hole overlap probability, increasing the radiative recombination probability, and adjusting the non-equilibrium carrier transport, etc., to improve internal quantum efficiency.

(4) The new structure of the chip

The new structure requires the chip hexahedral light uses a new technology, a variety of surface roughening at the chip interface, reducing the probability of photon is reflected at the chip interface, and increase the surface transmittance, in order to improve the chip the external quantum efficiency led driver.