Solar powered microchips put batteries in the shade

In a new, more efficient approach to solar powered microelectronics, researchers have produced a microchip which directly integrates photovoltaic cells. While harnessing sunlight to power microelectronics isn't new, conventional set-ups use a separate solar cell and battery. What sets this device apart from is that high-efficiency solar cells are placed straight onto the electronics, producing self-sufficient, low-power devices which are highly suitable for industrial serial production and can even operate indoors.
The autonomous microsystem was developed by the Semiconductor Components group at the University of Twente's MESA+ Institute for Nanotechnology led by Professor Jurriaan Schmitz. The researchers collaborated with colleagues from Nankai University in Tianjin, China and the Debye Institute of Utrecht University. The research was made possible by the STW Technology Foundation.
Instead of manufacturing the solar cell separately, the design sees the chip used as a base and the solar cell applied to it layer by layer. According to the UT release, this results in a more efficient production process, uses fewer materials and ultimately performs better.
The production process has not been trouble-free with the researchers finding that the fragile electronics can easily be damaged. For this reason it was decided to use amorphous silicon or CIGS (copper - indium - gallium – selenide) solar cells. The manufacturing of these cells does not influence the electronics, and these types of solar cells also produce sufficient power to allow the microprocessors to operate in low-light or indoors. There is a catch though – the chip's energy use must be well below 1 milliwatt.
Tests have shown that the electronics and the solar cells function properly, and the manufacturing process is also highly suitable for industrial serial production with the use of standard processes.
The paper Above-CMOS a-Si and CIGS Solar Cells for Powering Autonomous Microsystems by J. Lu, W. Liu, C.H.M. van der Werf, A.Y. Kovalgin, Y. Sun, R.E.I. Schropp and J. Schmitz was presented at the International Electron Device Meeting in San Francisco in December.

Samsung to unveil next-gen flexible and transparent AMOLED displays at CES 2011

There’s bound to be all manner of display technologies vying for eyeballs at CES 2011 when it kicks off in Las Vegas next week and two prototype AMOLED displays from Samsung Mobile Display (SMD) will definitely be high on our list of things to check out. The first is a 4.5-inch 800 x 480 (WVGA) resolution flexible AMOLED display concept prototype for mobile devices, while the second is the world’s largest transparent AMOLED display prototype for use in PC monitors and TVs.

Flexible AMOLED display prototype

SMD’s 4.5-inch flexible AMOLED display is two millimeters (0.08-in) thick and can be rolled down to a radius of one centimeter (0.39-in). The concept prototype’s 800 x 480 resolution, which Samsung claims is four times that of the previous most flexible AMOLED prototype constructed, comes courtesy of a new plastic substrate that can withstand the 450-500 degree Celsius temperatures required in the manufacturing process.
As this overcomes the problem of previous plastic materials melting during the manufacturing process that made commercialization of such devices difficult, Samsung says the concept display on show marks a major step on the road to mass production for the next-gen display, which is aimed at smartphones and tablet PCs.

Transparent AMOLED display prototype

The second prototype display to be unveiled is aimed at larger screen applications such as TVs and PC monitors. The 19-inch transparent AMOLED display prototype sports a qFHD (quad Full High Definition) resolution. This is a non-standard resolution of 3840 x 2160 pixels arranged in a 16:9 aspect ratio that gets its name from being four times the resolution of 1080p.
The prototype display is the world’s first large transparent AMOLED display prototype and, while the average amount of transparency previously achieved has been below 10 percent, SMD’s display maintains up to 30 percent transparency whether it is turned on or off. Samsung says this will allow the technology to be used for surfing the internet while watching TV or even watching TV on windows – and by that it means the glass kind, including car windows, not the operating system.
As well as the 19-inch prototype, SMD will also be exhibiting a 14-inch qFHD transparent AMOLED display designed for notebooks.