LED manufacturing industry
Optogan’s chip assembly within the newly installed LED component and module factory in St. Petersburg
and guide the light, or remove sidewall scribing damage and increase light dispersion by roughening the sidewalls. Absorption by metal contacts is another issue, which we address with some very simple approaches. We limit the area of this contact and suppress current injection into the active region under the contacts with current blocking layers (see Figure 1 g).
Forming a good p-type contact to any visible nitride LED is challenging. The p-GaN surface must be predominantly covered with contact material to ensure uniform current spreading and minimised contact resistance. Consequently, if the LED is to exhibit high emission efficiency, either highly reflective or highly transparent p-contact materials are mandatory, depending on chip geometry. This sets challenges for the correct contact material and structuring of the selected material.
Putting it all together Making LEDs that excel in light extraction requires optimisation of the chip architecture on several fronts. A tremendous amount of research related to this is ongoing, and a search of the literature reveals that more than 2000 papers were published on this topic last year. Given this high
level of research activity, it is not surprising that there are a multitude of schemes for extracting more light from the LED. The portfolio of light extraction technologies is actually a mixed blessing, because not all the schemes are suitable for LED manufacturing. Selecting those that are most appropriate is of paramount importance – one trap for the unwary is the approaches that promise incredibly high levels of light extraction, but are impractical, complex, and difficult to integrate into the LED.
We are devoting a great deal of time and effort to selecting a handful of technologies for light extraction that can work together to create LEDs with cutting-edge performance. This effort is already paying dividends, with our in-situ epitaxial and ex-situ mask-less approach (see Figure 2) yielding a 187 percent improvement over our previous generation of LED chips.
However, we know that we still have a long way to go on the road to the production of LEDs with incredibly high values of extraction efficiency.
© 2011 Angel Business Communications. Permission required.
The Optogan Group manufacturers innovative, competitively priced, high- brightness chips, LED components, LED lamps and LED luminaires. Three Russian scientists and entrepreneurs in Helsinki, Finland founded the company in 2004, and the following year this start-up began developing chip technologies in Dortmund, Germany. Currently the new production facilities for LED assembly in St. Petersburg, Russia, and high volume chip production in Landshut, Germany, are ramping up.
of which is taken up by a clean room environment. The first production line has an annual production capacity of 360 million LEDs and further capacity extensions are scheduled.
The manufacturing plant in St. Petersburg was opened on 29 November 2010 by Deputy Prime Minister of the Russian Federation, Sergey Ivanov. With an overall investment of 3.35 billion rubles (80 million euros), it is the largest LED component and module factory in both Eastern Europe and the Commonwealth of Independent States. The factory, which will employ up to 800 people, covers 15,000 m2 m2
High-brightness chip technology currently
ramping up at the new
Optogan facility in Landshut, Germany
FURTHER READING V.E. Bougrov et al. LED
professional Review 18 42 (2010) T.-X. Lee at al. Optics Express 15 6670 (2007)
of floor space, 5,000
June 2011
www.compoundsemiconductor.net 49
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122 |
Page 123 |
Page 124 |
Page 125 |
Page 126 |
Page 127 |
Page 128 |
Page 129 |
Page 130 |
Page 131 |
Page 132 |
Page 133 |
Page 134 |
Page 135 |
Page 136 |
Page 137 |
Page 138 |
Page 139 |
Page 140 |
Page 141 |
Page 142 |
Page 143 |
Page 144 |
Page 145 |
Page 146 |
Page 147 |
Page 148 |
Page 149 |
Page 150 |
Page 151 |
Page 152 |
Page 153 |
Page 154 |
Page 155 |
Page 156 |
Page 157 |
Page 158 |
Page 159 |
Page 160 |
Page 161 |
Page 162 |
Page 163 |
Page 164 |
Page 165 |
Page 166 |
Page 167 |
Page 168 |
Page 169 |
Page 170 |
Page 171 |
Page 172 |
Page 173 |
Page 174 |
Page 175 |
Page 176 |
Page 177 |
Page 178 |
Page 179 |
Page 180 |
Page 181 |
Page 182 |
Page 183 |
Page 184 |
Page 185 |
Page 186 |
Page 187 |
Page 188 |
Page 189 |
Page 190 |
Page 191 |
Page 192 |
Page 193 |
Page 194 |
Page 195 |
Page 196 |
Page 197 |
Page 198 |
Page 199 |
Page 200 |
Page 201 |
Page 202 |
Page 203 |
Page 204 |
Page 205 |
Page 206 |
Page 207