Global semicon trends and spotlight: UWB and PV developments

Here are the excerpts from the Global Semiconductor Monthly Report, March 2010, provided by Malcolm Penn, chairman, founder and CEO of Future Horizons. This post covers market trends and semicon developments. Those interested to know more may contact Future Horizons.

Market trends – UWB
Ultra-wideband (UWB) is a low power, short-range radio technology that uses a large portion of the radio spectrum to carry high bandwidth data. UWB uses pulse-coded information with sharp carrier pulses using a number of centre frequencies. It has traditional applications in radar imaging.

As well as transmitting data, it has been used for sensor data collection as well as precision locating and tracking applications. UWB communications transmit in a way that should not interfere with other more traditional 'narrow band' and continuous carrier wave used in the same frequency band.

However studies have shown that a number of UWB transmitters increases the noise level and can make traditional communications services more difficult in proximity to the UWB transmitters. This may affect the stability and reliability of existing systems.

Ultra-wideband (UWB) is an unlicensed radio technology that can provide audio/video data streaming over short distances. It is expected to deliver the bandwidth and Quality of Service (QoS) for multi-channel consumer video equipment in the home, which is more difficult for other data transmission technologies like WiFi.

UWB transceivers can communicate at a data rate of up to 480Mbits/sec and operate at 3.1 to 10.6 GHz. ISO/IEC and also the European Commission have approved the standard. As well as streaming high-definition video, UWB can also be used for transferring digital data between domestic entertainment and computer equipment.

Agreeing standards is problematical but UWB is a good concept. It uses a wide slice of the radio spectrum, is efficient, and sends data at almost minimal power over a short distance. Technically it is quieter than background radio noise, yet it can theoretically transmit data signals of 480MBits/s. Realising this potential has been more difficult in practise.

Lack of agreement in UWB technology choice was beginning to hinder the market potential for UWB as established wireless LAN (IEEE803.11) has developed higher bandwidth solutions in the new ‘n’ specification, which has the possibility to steal some applications in higher speed media streaming.

The lack of agreement caused the IEEE Standards Association to disband the IEEE 802.15.3a Task Group. Nevertheless, some of the world's top chip firms still consider the UWB market important, especially for the high volume and potentially lucrative home consumer market. The industry was helped, during 2006, by some more concrete applications for wideband wireless Bluetooth version 3.0 and wideband wireless USB links.

On 28 March 2006, the Bluetooth Special Interest Group announced its selection of the WiMedia Alliance Multi-Band Orthogonal Frequency Division Multiplexing (MB-OFDM) version of UWB for integration with current Bluetooth wireless technology (although it does also see the Bluetooth protocol stack being used with WiFi as well). However, in 2009, the Bluetooth SIG made an announcement concerning Bluetooth 3.0 High Speed, which (notably) did not mention UWB and only 802.11 as the physical layer, which must come as a warning sign for UWB technology.

Unfortunately, UWB has seen a number of technical and standards issues and although the technology shows some promise, the full potential has yet to be realised. Despite the initial optimism over the use of UWB a number of companies have either been taken over or ceased operations. Tzero Technologies joined a shakeout of UWB manufacturers in 2009 that also claimed Focus Enhancements. WiQuest and Artimi also merged with Staccato to pool resources. Intel also announced that it was stopping development in November 2008.

Bluetooth technology using the UWB physical radio layer has the capability to meet the high-speed demands of synchronising and transferring large amounts of data but at the moment appears to be beset by technical problems with a very much lower than expected data rate in current silicon. However, these problems are likely to be temporary and it could still be an ideal solution to enable high-quality video and audio applications for portable devices, multi-media projectors and television sets.

Home video networking applications cannot easily be met using existing wirebased technologies (for installation and aesthetic reasons), and modified existing wireless technology is struggling to meet the latest video networking requirements. UWB could resolve most of these issues at least in a single room -- at short range. It does, however, need the broad agreement of the consumer electronics industry on standards for this to happen. If it does, then home video networking applications could drive UWB with connections likely to be seen on a broad range of consumer products.

In summary, UWB has lost some traction because of standards and technical problems, but Future Horizons believes the technology is delayed rather than dead and our forecast for unit sales shows steady growth from 2011 onward.


Semiconductor spotlight – Photovoltaic developments
Photovoltaic (PV) cells are arrays of cells that convert radiation from the sun into (direct current) electrical energy. This conversion happens without intermediate steps although the efficiency of the conversion can vary. Semiconductor materials used for photovoltaic devices include various types of silicon and other semiconductors with dopants including boron and phosphorus.

The increasing interest in green energy sources including photovoltaic modules has spurred research and development in PV especially in the last four years. Production has been increasing, especially, as government grants and incentives have become available for smaller installations.

Although the total power produced by PV modules installed worldwide has increased significantly in the last two years it is still a very small percentage of the electricity produced by fossil fuels and is still far behind nuclear power stations. The worldwide production from photovoltaic sources is approximately 21 Gigawatts and for nuclear is 370 Gigawatts.

The PV effect is caused by photons of light stimulating electrons into a higher state of energy. When a photon is absorbed, the energy of the photon is transferred to an electron in an atom of the semiconductor cell photodiode. The higher energy electron is able to escape from its ‘normal’ position associated with the atoms in the material to become part of the current in an electrical circuit. The absence of the electron in its usual position causes a hole to form and the current flows through the PN junction with enough voltage and current to drive a load viz.charge a battery or light a light bulb.

Polysilicon (c-Si) is the primary material of wafers used to fabricate crystalline silicon solar cells but cheaper alternatives are being developed such as thin film (CdTe) casting wafers instead of sawing, thin film copper indium gallium and selenium (CIGS), as well amorphous and microcrystalline silicon.

Almost all photovoltaic devices are an adapted photodiode with a large light collecting area. The semiconductor interest is primarily in the PV cell itself, but there is also the need for control and management of the system using microprocessors and also the components necessary for the inverter.

The inverter is needed to bring the low voltage direct current battery or from the solar cell to AC mains voltages for use in the premises or for onward transmission to the grid. Advances in technology and increases in manufacturing competence have resulted in price reductions for PV solar cells and modules, which is typical of other semiconductor devices.

Financial incentives, including attractive feed-in tariffs for solar-generated electricity, have also led to growth of solar PV installations in many countries where these incentives exist. Australia, China, Germany, Greece, Israel, Japan, Spain and the United States are examples of countries where incentives are offered and others are set to follow.

Solar PV installations can either be stand-alone or connected to the grid depending on the location. Stand-alone applications include cellular base stations, telemetry, electrical power for remote buildings, rural communities, parking meters and emergency telephones. Grid connected systems are used in houses and in industrial buildings as a supplementary source of power. Some more extensive arrays for commercial energy production are also grid connected.

Many governments are pushing green energy and solar cells and arrays are important components in the mix of renewable energy options, especially for smaller installations and also on a larger scale in more extensive arrays in suitable locations. Because of this, the demand for PV cells has almost doubled every two years for the last seven years, despite the relatively high cost of installation and a long time for payback (tens of years).

Further reductions in the cost of PV installations will reduce this payback and encourage future market growth. The main suppliers of PV modules include Suntech, Sharp, JV Solar, Q-Cells, BP Solar and SunPower.

The economic downturn did have an effect on the PV market but it has shown some resilience and despite a build up of inventory in the early part of 2009 the inventory has mostly been consumed during the upturn in the second half of the year. The forecast in the figure shows the growth in the generation capacity of PV modules to 2014.

Thin film based technologies will grow its share of total production from 15 percent in 2008 to over 35 percent by 2014. The technology is advancing and prices are falling which will encourage uptake. On the other hand, this growth will be negatively affected by the gradual reduction of government subsidies either as direct grants or the benefit of generous feed-in-tariffs.

To summarise, the PV market is still growing and is forecast to grow at a CAGR of 54 percent between 2008 and 2014. The effective price of PV silicon and modules will reduce by approximately 40 percent during the same period, which will encourage this growth. The forecast does not include the essential peripherals such as inverters, which will also add to the semiconductor total for these installations.