Power semiconductor devices play a leading role in improving technologies in the various fields of industry, information, consumer goods, car electronics, and so on. Low loss technology has made much progress such as reduced MOSFET on-state resistance, third-generation insulated-gate bipolar transistors, and MOS gate thyristors. Wide-ranging intelligent devices such as intelligent power modules and switches have been developed into product series. The application of MOS gate power semiconductor devices are rapidly expanding in traction uses, resonance type inverters, and use in space.

Demand for improvement in efficiency, noise, functions and size has been increasing in the field of power electronic equipment such as general-purpose inverters, numerically controlled machines, and industrial robots.
To meet this technical trend, applying a newly developed special IC using a third-generation insulated-gate bipolar transistor (IGBT) for the output stage power device, Fuji Electric has developed a high-speed, low-loss, IGBT output type intelligent power module incorporating various protective functions, and completed a product series.

Fuji Electric has developed 1,400V class IGBT modules applicable to inverters with 575V AC input. Rated current is 50 to 400A. These modules have the same package as 1,200V class IGBT modules (460V AC input) at the same collector current rating and equal power dissipation loss to 1,200V ones at the same capacity PWM inverter application, so that common design can be applied to both AC inputs. To secure RBSOA and short-circuit duration rating, chip design was optimized and an overcurrent limiting system was adopted. These modules will enhance the improvement of performance in various high-voltage inverter applications.

The use of insulated-gate bipolar transistor (IGBT) modules in place of GTO thyristors in vehicle inverter circuits is now under way. Fuji Electric has developed a 2,000V, 400A IGBT module of the largest capacity in the word usable for vehicle-use 3-level inverters. Compared with GTO thyristors, this module has high-speed switching and low saturation voltage characteristics as well as insulating construction, and its use will reduce the size and noise and improve the maintainability of equipment. The application of IGBTs to vehicles will make a rapid progress and greatly contribute to performance improvement.

Fuji Electric has developed a 2.5kV 100A μ-stack insulated-gate bipolar transistor (IGBT) of a flat, pressure-contact type. This is the first high-voltage, high-current, high-reliability, pressure-packaged MOS controlled device. Four pressure contacts formed on a chip 20mm square act as an electrode for the emitter and a cooling means. The IGBT showed a high blocking voltage above 2.5kV, a saturation voltage below 4.0V (100A), a turn-off time below 1.0μs, and a turn-off capability above 300A.
The contact pressure for electrical and thermal characteristics ranges from 100 to 800kgf/chip.

Fuji Electric has continued developing a high-speed, high-performance molded insulated-gate bipolar transistor (IGBT). This paper describes the technical progress of the following two types of IGBTs for microwave ovens, rice cookers, TV sets, and monitor displays:
(1) IGBT with a built-in FWD
(2) IGBT for the horizontal deflection output of a CRT.

With the increase of power devices used in automotive electronics, demanded are small, light, cheap, intelligent power devices incorporating a drive circuit and protective functions.
To meet the requirements, Fuji Electric has continued developing the elementary technology of MOS output type high-side intelligent power switches (IPS) for automotive use. This paper introduces newly developed process technology characterized by high cost performance being applied high-side IPSs with a rating of 60V/6A.

As automobile requirements for safety and environment became severer year after year, impetus has been given to improvement in automobile electronics and semiconductors to meet the requirements. Fuji Electric has developed a low-side intelligent power switch F5015L (60V-10A-80mΩ max,TO220F-5pin) incorporating overcurrent, overtemperature and overvoltage protecting functions, an output inhibit function, a drive circuit, and an inductive-load counter-electromotive-force clamping circuit, by means of a low-cost, self-isolated NDMOS process.

Fuji Electric finished optimizing the structure and manufacturing conditions of a MOSFET chip that satisfies resistance against radioactive rays and immunity to environment and has a low on-state resistance, and then completed a new design for the package.
As the result, the MOSFET met the targets of resistance against single-event burnout and total dose and proved to be highly reliable.

This paper describes the present status of numerical device simulation techniques, which have become indispensable to advanced device development. It has become possible to analyze device operation in a specific application circuit as well as to predict circuit performance using device-circuit mixed mode simulation and electrothermal simulation including lattice heating. A prediction of IGBT inverter circuit performance and an analysis of the mechanism of IGBT destruction under a short circuit are presented as examples.

The oxidation and diffusion process of MOS gate power devices shows a high ratio to the whole causes of yield decrease due to chip size enlargement. The subject of a top priority for yield improvement in this process is the reduction of heavy metal contamination. This paper introduces recent topics from among Fuji Electric's research and development for this subject such as technologies of process evaluation, contamination source inspection by means of analysis, and gettering.

Power semiconductor modules have developed with the expansion of power electronics. Fuji Electric has recently developed and systematized a integrated power module that satisfy market requirements for small size and integrated functions. The module is a small, thin package into which semiconductor chips for the inverter, converter, and brake circuit of an inverter system are integrated. Its special features are that the inverter circuit uses second-generation or third-generation insulated-gate bipolar transistor (IGBT) chips and the package can be mounted on a printed circuit board.