Identification of gallium nitride based flip chip power LED

February 15th, Chinese semiconductor institute innovation project "GaN based flip chip structure of power semiconductor light emitting diode (LED) and the key technology achievement appraisal by.

The core technology semiconductor lighting is high brightness Gan and AlGaInP materials such as the representative of the two luminescence tube, semiconductor solid foundation in this field of research for several years research results and a good research research team, innovation has its own characteristics in the core technology. In June 2004, the semiconductor "GaN based flip chip structure of power type semiconductor light emitting diode (LED) and semiconductor technologies" in the knowledge innovation project, and investment funds, on the GaN based high power blue and white LED design, manufacture and batch production of the key technologies to carry out research.

Traditional small power LED and power LED usually adopting the structure, with power, working current and chip size increases, there are many problems in the structure, the influence of light efficiency and reliability. After the efforts of scientific research personnel, the use of the inverted structure power LED design, to solve the problem of the existence of the formal structure of the structure, so that the project made breakthroughs in key technologies. Appraisal committee that: GaN based flip chip power semiconductor light-emitting diode (LED) and key technologies, successfully developed a gallium nitride (GaN) - based flip - chip power type blue, white LED. The development of testing Chinese Institute of Metrology blue power LED at 350mA current, the forward voltage is less than 3.5V, the highest power of 189mW blue light, white light, the highest luminous efficiency is 47.5lm/W, the color coordinates (0.335,0.338), 5413K color temperature, color rendering index greater than 80. Comprehensive indicators in the domestic leading position, some indicators exceed the international market in 2005 the same device product indicators.

Experts believe that the design method of flip chip LED the project has developed a self intellectual property of light, electricity and heat integrated simulation, first proposed and implemented a flip chip power LED with low thermal resistance of heat sink back hole structure transition in the world, the development of integrated technologies should be the optimization; the plasma enhanced chemical vapor deposition (PECVD) and inductively coupled plasma (ICP) etching P type gallium nitride (P-GaN) conditions, the development of a low damage PECVD mask deposition and low damage without contamination of ICP etching technology; the development of a new type of low contact resistance is composed of non metals such as nickel and gold. High reflectivity and high reliability de P metal electrode system; N electrode metal system developed with high reliability and low contact resistance.