As environmental problems evolve into serious social issues, power semiconductor devices offer promising solutions. The status and future outlook for the major product groups of power semiconductor devices are described. The V-series of the latest 6th generation IGBT and high power IGBT modules are introduced. The newly developed E³-series of high voltage MOSFETs and several low-loss and smallsize power ICs are introduced. Finally, COC (chip on chip) package assembly technology is described for new integrated automotive-use trench MOSFETs.

The IGBT module for hybrid vehicles introduced here is able to contribute to reducing the inverter size and improving the energy efficiency by means of regenerative braking. By this we meet the needs for further improvement in fuel consumption and cost reduction of hybrid vehicles.
This hybrid IGBT module has realized both of the improvement of inverter conversion efficiency and the reduction of module size by applying field-stop type trench-gate IGBT for 600 V application. Further, the power recovery efficiency at operation of a regenerative brake was improved by optimizing the free wheel diode chip size. Also, the response of the sensor to a transient temperature rise of an IGBT chip was improved by using the built-in on-chip temperature sensor in IGBT.

Markets for new types of energy such as wind power and solar power, which do not use fossil fuels in order to limit global warming, have been growing rapidly. Targeting applications in this new energy sector, Fuji Electric has redeveloped high-power IGBT modules. They are equipped with the U4 chip, improved thermal characteristics and environmental requirements. They have rating voltage of 1,200 and 1,700 V, and have rating current of 600 to 3,600 A. The package dimensions are 130×140 mm or 190×140 mm, and are configured as 1-in-1 or 2-in-1 modules.

The further miniaturization and increase in efficiency of power devices play an important role in protecting the global environment. In response to requests for higher efficiency, higher performance, lower cost and stable supply in IPMs (intelligent power modules) that integrate an IGBT driver IC into a single package, a small-size highperformance driver IC for IPMs has been developed and is introduced in this paper.

500 to 600V products of the SuperFAP-E³ Series, which supports the key challenges of higher efficiency and lower noise in switching power supplies, were commercialized in 2007, and a 900 V product of the same series has recently been developed. In particular, since the 900V product is a high-voltage product, the avalanche resistance and gate voltage V_GS wringing characteristics were improved, and an easyto- use product having lower loss and higher resistance to damage was developed. This paper presents an overview of the SuperFAP-E³ 900V series.

Demand for higher efficiency of switching power supplies is increasing rapidly, and the simultaneous realization of low switching loss and low noise is essential for switching devices. Fuji Electric's newly developed SuperFAP-E^3S low Q_g series realizes an improved tradeoff between switching loss and noise due to a reduction in gate charge Q_g of approximately 20% compared to prior devices and optimization of gain (g_fs), while maintaining the industry's lowest ON-resistance with the planar-type MOS structure of existing products. Moreover, a system-wide improvement in power efficiency and a lower rise in temperature were realized as a result of application.

A trench MOSFET product series having low ON-resistance, high gate threshold voltage and high reliability has been developed for electric power steering systems and the DC-DC converters in hybrid automobiles and the like. Aiming to improve fuel economy and to reduce the environmental load of automobiles, a reduction in the consumption of electric power by automotive electrical components is sought, and even lower ON-resistance is being requested of MOSFETs for automotive- use. In response to these requests, a new type of trench MOSFET has been developed with finer design rules for the trench structure.

Fuji Electric has developed an intelligent power MOSFET "F5060L" that incorporates an open-load detection circuit and status output circuit, and realizes lower on-state resistance of 350 mΩ (max) compared to the 600 mΩ (max) of Fuji's prior device. The F5060L realizes lower on-state resistance due to quasi plane junction (QPJ) wafer process technology and finer IC circuit line widths and smaller chip size due to 3rd generation 1.5 μm self-isolation process technology. Even with these functional and performance enhancements, a 2-channel chip can housed in the conventional SOP-8 package.

The issue of global warming has garnered attention in recent years, and efforts to increase the efficiency and reduce the standby power consumption of LCD TVs, audio equipment, PCs and the like have become key challenges, and energy-saving specifications such as International Energy Star Program are being upgraded to stricter ones. Fuji Electric is advancing the development of a series of switching power supply controller ICs that incorporate starting elements and that is effective in realizing low power consumption. This paper presents Fuji's series of quasi-resonant power supply controller ICs which reduce standby power consumption by operating intermittently or at low frequency during light load or unloaded states while the electric product is in its standby state.

In recent years, stricter standards for energy savings and harmonic regulations are being requested for all electric products; active filtering is being used to suppress harmonic current and highly-efficient lownoise current resonance methods are increasingly being employed in offline converters. This paper presents an overview of Fuji Electric's newly developed combo-IC for critical conduction mode PFC and current resonance. The results of a power supply evaluation of this IC verified its applicability for high power factor, high efficiency and low standby power applications.

With the recent and sudden rise in popularity of digital home appliances and the expansion of the market for industrial-use digital equipment, higher efficiency, smaller size, higher reliability and the ability to operate at lower voltage are being required of products, and buck converter ICs must support such operating requirements. In response to these market requirements and in order to achieve higher efficiency, higher frequency, higher reliability, lower voltage and fewer external parts than prior models, Fuji Electric has developed a hiccup-operation type buck converter IC that incorporates a high side n-channel MOSFET having a load current of 1.5 at 45 V, and also has built-in current mode control and phase compensation.

Portable type electronic equipment such as digital still cameras is required to be small in size, lightweight and to achieve extended battery life operation. The power supplies used in these devices are also required to be small, lightweight, and have low current consumption and high efficiency. Fuji Electric has developed the FA7763R, a 7-channel DC-DC converter that incorporates a power MOSFET and supports synchronous rectification and current mode control for multi-channel power supplies.

To support the safety, comfort and energy savings required by automobiles and to address environmental problems, many vehicle components are being designed as electronic components. These electronic components must be highly reliable to operate under the severe conditions when installed in an automobile. To support operational compatibility with the various assumed electrical stresses and conditions in an actual vehicle, Fuji Electric has developed a sophisticated ignitor that is provided with its own protective function. Furthermore, in order to continue using the traditional small package size, a circuit configuration in which power supply voltage is the ON-voltage and a fine line process were applied in the development of this ignitor.

In the automobile industry, efforts to address environmental issues have increased with the strengthening of regulations, and the importance of achieving increased accuracy and efficiency of automotive engine management and the importance of pressure sensors, which are a key device, are increasing. This paper describes a newly developed small atmospheric pressure sensor that uses a 5th generation digital trimming type pressure sensor chip and that can be mounted as a surface mount device (SMD) on an ECU board for use in high altitude compensation when an automobile travels at a high elevation. This newly developed sensor is approximately 65% the size of our previous sensor.

Thermal design has become an increasingly important factor in the development of power conversion equipment that use semiconductor devices, and Fuji Electric has developed and released an IGBT/FWD power loss simulation tool (ver. 4) which is based on a one-dimensional thermal resistance model and enables the easy computation of dissipation loss and temperature rise of an IGBT module in an inverter circuit. This version of the simulation tool adds a computation function that considers the thermal resistance of heatsinks and a function that continuously calculates the dissipation loss and temperature according to a variable load pattern. As a result, computations can be made based on the actual operation of equipment that uses Fuji Electric's IGBTs.

The development of computer and simulation technology enables noise levels to be predicted with a high degree of precision and shorter lead times for design. Fuji Electric used a PSIM simulator to reproduce common-mode leakage current, and then verified that the noise reduction effect of the simulation results matched that of the experimental results. This paper proposes an active filter, which is used to cancel common-mode voltage, realizable as a compact-size low-voltage filter since the detected common-mode voltage is divided by the stray capacitance of the motor and capacitors connected to ground.

Trench filling epitaxial growth technology used for filling deep trenches fabricated on a silicon substrate is introduced. Optimizing the selected epitaxial growth conditions and crystalline direction for fabrication of the trenches enables the trenches to be filled without any voids. A super junction substrate can be fabricated by introducing impurities when filling the trenches. SIMS and SCM were used to verify that the distribution of impurities was uniform in super junction substrates fabricated by trench filling.

In support of trends toward smaller sizes and higher reliability of automotive electrical systems, Fuji Electric has developed automotiveuse intelligent powers switches (IPS) that use a self-isolation process to integrate output stage power devices and peripheral circuitry into a single chip. This paper describes newly developed IPS device technology for automotive systems that combines improved vertical power device technology with 1.5 μm lateral CMOS technology. With this technology, size was reduced by 30 to 50% compared to prior devices, and the ON-state resistance per area was also reduced by 25%.

To enhance the performance of SiC power MOSFETs, technology for improving trench shape control and sidewall flatness was examined. The shape of a trench can be changed by annealing in an atmosphere of SiH4/Ar at 1,700^oC, and inner walls of the trench can be made flat, without changing the trench shape, by annealing in an atmosphere of H₂ at 1,500^oC. By sequentially performing the SiH₄/Ar annealing at 1,700^oC and then the H₂ annealing at 1,500^oC, the roundness of the trench corners and semicircular contour of the trench bottom can be controlled, and sidewalls of the trench can be made flat simultaneously. This technology is expected to help to increase device withstand voltage and to improve electron channel mobility.