Sunday, November 23, 2014
Search
  
Submit your own News for
inclusion in our Site.
Click here...
Breaking News
Regin Trojan Enables Stealthy Surveillance: Symantec
ASTC Says 100 TB HDDs Coming in 2025
Alienware Alpha PC Gaming Console Now Shipping
Samsung Files ITC Complaint Against Nvidia
Europe To Ask Google Unlink Its Commercial And Search Services
Streaming TV Service Aereo Files for Bankruptcy
Square Launches Cash Register Service
Call of Duty: Advanced Warfare is the Biggest Entertainment Launch of 2014
Active Discussions
cdrw trouble
CDR for car Sat Nav
DVD/DL for Optiarc 7191S at 8X
Copied dvd's say blank in computer only
Made video, won't play back easily
New Features In Firefox 33
updated tests for dvd and cd burners
How to generate lots of different CDs quickly
 Home > News > Optical Storage > Sharp I...
Last 7 Days News : SU MO TU WE TH FR SA All News

Friday, June 24, 2005
Sharp Improves MBE-grown Blue Laser Performance


Engineers at Sharp's research laboratory in the UK have fabricated the first continuous-wave InGaN-based laser diodes to be grown by MBE.

All commercial blue-violet laser diodes are grown by MOCVD currently, but early last year Jon Heffernan and colleagues at Sharp Laboratories Europe produced 405 nm diodes using MBE for the first time.

One key advantage of the MBE method is its much lower consumption of source materials for device growth, in particular the amount of ammonia required as the source of nitrogen.

However, those initial devices only worked in pulsed mode and had a very high threshold current. To be used commercially, the lasers need to work continuously and at sufficient power to read data on optical discs.

"This result confirms that MBE is a viable growth method for nitride lasers," said Heffernan. "Sharp is now in the unique position of having both MBE and MOCVD technologies available."

At room temperature, the Sharp team?s latest lasers emitted around 0.2 mW for three minutes before burning out. The continuous-wave threshold current was 125 mA, corresponding to a threshold current density of 5.7 kAcm-2, reports the team in the June 23 issue of the journal Electronics Letters.

Heffernan and colleagues made the lasers on n-type GaN substrates supplied by Sumitomo Electric Industries. The active laser region included three undoped 3 nm-thick InGaN quantum wells with 10% indium fraction.

During the three minutes that the lasers worked for, there was a variation of around 6 nm about the crucial emission wavelength of 405 nm.

Growing the lasers by MBE rather by MOCVD promises to lower manufacturing costs by reducing the consumption of ammonia gas, which provides the nitrogen content in the devices.

However, Heffernan and colleagues still have a lot of development work to do before the MBE method can be considered suitable for mass production. The team will now concentrate on improving device operating characteristics by optimizing p-type doping in the AlGaN cladding region and reducing the growth temperature, which should increase the lifetime of the devices.

Significantly, the European laboratory's parent company already uses MBE in mass production of lasers. At its Mihara fabrication facility in Hiroshima, Sharp manufactures a large proportion of the world's red lasers that are used in DVD applications.

Sharp is also part of the Blu-ray Disc Association, along with potential blue laser manufacturers Nichia, Sony and Matsushita Electric.


Previous
Next
UMD Format Approved by ECMA        All News        Sony, Toshiba Push Their Own Standards for Next-Generation DVD
Teac Unveils 8x DVDR DL Burner     Optical Storage News      Sony, Toshiba Push Their Own Standards for Next-Generation DVD

Get RSS feed Easy Print E-Mail this Message

Related News
Sharp Showcases 4.1-inch, 736ppi IGZO LCD Prototype
Sharp 2Q Profit Slides
Sharp To Produce New Backlight-free LCD Panel For Wearables
Sharp To Start Making 4K Displays For Smartphones
Sharp Licensing TV Brand in Europe to Slovak Universal Media
Sharp Pushes Back Production Of Energy-efficient MEMS-IGZO Displays
Sharp, Pioneer Dissolve Their Capital Alliance
Sharp Launches 12-Mpixel CMOS Sensor for 4k Video
Sharp Brings Bezel-free Smartphone To The U.S.
Chinese Smartphones Boost Sharp's 1Q Operating Profit
Sharp Develops Brighter LED for LCD Backlights
Sharp to Exit TV And Home Appliance European Markets

Most Popular News
 
Home | News | All News | Reviews | Articles | Guides | Download | Expert Area | Forum | Site Info
Site best viewed at 1024x768+ - CDRINFO.COM 1998-2014 - All rights reserved -
Privacy policy - Contact Us .