Researchers study doping of zinc oxide for LEDs

German researchers say they've made a discovery that could open the use of zinc oxide as a semiconductor, creating new possibilities for use in light-emitting diodes (LEDs).

A team of chemical scientists at the Ruhr University in Bochum said they found a way to overcome the problems that occur when doping zinc oxide with hydrogen atoms. The findings are the basis for the production of higher-performance zinc-oxide electronic circuits.

Doping is necessary to activate semiconductors. The process involves inserting foreign atoms into the crystal lattice of a solid.

But scientists have struggled with p-doping, in which the hydrogen would absorb an electron and create a hole in the zinc oxide. P-doping is necessary to create LEDs and transistors.

The researchers discovered that hydrogen atoms always result in n-doping, in which foreign atoms either release an electron. The scientists found they could reversibly dope zinc oxide substrates using hydrogen and then eliminate the hydrogen by heating.

According to ScienceDaily, the problem is that hydrogen atoms disturb the process. The scientists found that controlled concentration of hydrogen atoms during the production of intrinsic zinc oxide is the key to using zinc oxide as a semiconductor.

Zinc oxide also has uses in food additives, sunscreen (see Carbon capture gets crystal powered), and thin-film solar panels (see Oerlikon sees 50% gains in thin-film fab).

Read the article »

Cleantech developments making news in the past 24 hours

• Nexamp closes Series A round, brings on new CEO
• Water innovation beyond desal: the new opportunities?
• Areva to launch solar business with Ausra takeover

View the last week of cleantech developments here | Subscribe to full feed