A VIEW ON THE POWER SEMICONDUCTOR MARKET

Power semiconductor components are at the core of any power electronic converter.

They have a history of more than 50 years, reach in technology development and market success. Since the technology behind these devices is not new, the differ-ences between the newly released components and the role of these changes are not always easy to understand for a student. For this reason, a brief market survey is herein presented with the goal of outlining why efforts are made for certain perfor-mance indices of the power semiconductor devices. It is also important to understand the specifics of the semiconductor industry. Since production is based on large capi-tal equipment, the technology development is done in a cyclical manner.

Power semiconductor devices are at the heart of many modern industrial and con-sumer end-use applications and come in different size and ratings. The application objectives are ranging from low power supplies of tens of watt to 4 MW locomotives or 10 MW steel rollers.

The power discrete market was estimated at $12.9 billion in 2011, having grown by just over 2% from 2010 [1]. It is worthnoting the continued high demand for dis-crete IGBTs that accounted for nearly all the growth. This was fuelled by new prod-ucts for domestic appliances such as room air-conditioning and washing machines targeting especially the Asian markets. Sales of standard power MOSFETs and thy-ristors declined slightly in 2011 given the limited new development within the eco-nomic crisis.

According to IMS Research, the market for power semiconductor modules grew faster than that for discrete power semiconductors in 2010, increasing by 32% to $4.6 billion. The power module market growth was continuing in 2012 despite slowing demand.

The power semiconductor devices most related to our book topic are MOSFET, IGBT, and diverse modern variations of thyristors (SCR). The last 20 years have seen spectacular improvement in technology and performance. The technological S-curves related to the power device capacity are shown in Figure 2.1 [4].

The power MOSFET device was introduced in early 1980s with starting param-eters of 3–5 A for the drain current, up to 400 V breakdown voltage and turn-off time in the range of 1.2 ms. Technology development allowed improvement of rat-ings to different sets of 9 A/600 V or 100 A/50 V and decrease of the turn-off time to 600 ns. The most recent technology advances include the CoolMOS devices that are able to switch 20 A/600 V with a turn-off time of around 100 ns. Among all sorts

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of MOSFET devices, the largest market increase is now seen in the high current applications where new devices are released continuously.

IGBT devices combine the advantages of bipolar and MOSFET transistors into a device dedicated to power-switching converters operated under high current and high voltage. These devices are the most useful for the class of converters pre-sented in this book, and we will dedicate more space to the presentation of IGBT’s parameters.

The history of IGBTs starts also in early 1980s, but the real technological advent was in late 1980s and early 1990s when several generations of IGBT devices have been developed by a series of companies. Snapshots of performance evolution are next included:

• 1986: starting parameters 50 A/600 V/3 ms

• 1990: commonly from 50 A to 400 A/1000 V/1.8 ms

• 1995: commonly from 50 A to 400 A/1200 V/1.3 ms

• 1996: 800 A/1600 V/1.6 ms

• 1997: 1200 A/3,3 kV/2.2 ms

• 2000: 50 A to 400 A/1200 V/0.4 ms to 0.8 ms

• 2000: 1000 A/3,3 kV are available in smaller series

• 2004: commonly 1000 A/1700 V/1.2 ms, in small series up to 1200 A/6 kV Given their application to high-power converters, the focus was on the improve-ment of parameters that relate to the power conversion. During the last 20 years, we have seen technology evolution with effects in

• Current handling capability—increased four times since 1982

• Voltage handling capabilities—increased four times

Device ratings (GVA) 100 10 1 0.1 0.01

Year 400 V BJT

80 A

IGBT

2000 V 400 A

3300 V 1200 A

4500 V 2000 A 8000 V

3500 A 1200 V

800 A

4000 V Thyristor

2500 V

Flat-packaged IGBT

1965 1970 1975 1980 1985 1990 1995 2000 2005 2500 V

1800 A

FIGURE 2.1 Technology S-curves with maximum device ratings as parameter.

• Turn-off time dropped 20 times, to around 100 ns today

• Switching frequencies from 2 kHz in early 1980s to 150 kHz in 1999 and 200 kHz nowadays

The evolution of the IGBT market was also impressive over the last 10 years. The 1995 world market for IGBT market was estimated at $200 million, the European market taking the largest share (approximately 45%). The global market increased to

$800 million in 2003, and it topped $1 billion in 2005.

All the above performance-related information refers to the limits of the IGBT technology. It is worthlooking also into the market depth. Most of the power converter applications are in lower power range (around kW) rather than the multi-100 kW power range. Also, the production volumes are higher in low kW power range. For instance, there are more inverterized A/C units than locomotives in the world. This explains why the number of vendors and the number of product variations are higher in the lower power range. Figure 2.2 shows a snapshot of all the IGBT product offering of a distribu-tor (digikey) for North American market, in November 2011. It is clearly shown that the most IGBT product types are for 600 V and <50 Amp ratings. Knowing the peculiar aspects of protection and control for these devices covers more applications than focus-ing on the multi-kW IGBTs. It is true that the companies with products in higher power range also work on direct supplier agreements rather than with distributors.

The success of power semiconductor devices in existing applications and the appearance of new applications encouraged the development of new concepts. Today, emerging high-frequency power semiconductor devices (Example 1–10 kW switched at 100 s kHz) are a very hot R&D topic.

1250 1200 1150 1100 1050 1000 950 900 VCEB (max) (V)

IC (max) (A)

850 750

700 650 600 550 500 450 250

NPT IGBT IGBT Products

FieldStop IGBT 200

150

100

50

0 800

FIGURE 2.2 Cumulative view on the digikey offer for IGBT, on November 2011.

Currently, the discrete power semiconductor devices target the following mar-kets [2]:

• IT and consumer for 33.9%

• Automotive for 12.5%

• Industrial equipment 23.8%

• Consumer appliances 29.8%

The first two categories use mostly lower power devices, and the last two are more related to our book. However, the advent of hybrid electric vehicle (HEV) power elec-tronics is expected to increase the market share of high-voltage automotive applications.

A special market segment refers to the integrated circuits dedicated to power management and motor control. This sector is very dynamic with large investments over the last years.

2.2 POWER MOSFET^s