In 1939, Schottky, a famous German physicist at Siemens, published "a quantitative interpretation of the space charge and surface layer theory of crystal rectifiers," which laid the theoretical foundation for Schottky barrier diodes.
In 1955, Siemens invented the trichlorosilane reduction method to produce high-purity polysilicon and the resulting zone melting purified single crystal silicon, the famous Siemens method and the later improved Siemens method. The zone melting single crystal silicon method (FZ) is still the main production method of power semiconductor materials.
In 1964, Siemens invented a bolt-type internal crimp structure to make silicon power semiconductor devices, and in 1965 invented a flat-plate external crimp structure, namely a flat-plate thyristor and a power diode structure.
In 1973, Siemens first used neutron transmutation doped single crystal silicon, which greatly improved the performance index of thyristor (SCR).
In 1980, Siemens launched the SIPMOS patent for power MOSFETs, gaining a large global market share.
In 1988, Siemens took the lead in launching a new transparent anode structure NPT-IGBT, due to its high reliability, low cost, MOS-like characteristics, influence, Siemens quickly determined its IGBT international standard name.
In 1990, Siemens' power semiconductor division (established in 1949) and Germany's AEG power semiconductor division (established in 1947), each holding 50% of the shares, merged to form the famous EUPEC company, specializing in the production of high-power power semiconductor devices.
In 1994, EUPEC launched the EconomoPACKTM IGBT module series, establishing the current standard for the packaging of EconomoPACK (six-cell), EconomoPIM (rectifier bridge + seven-cell) IGBT modules.
In 1995, EUPEC pioneered the 3300V IGBT High Voltage Module (IHV).
In 1996, EUPEC launched the world's first commercial 8000V light-triggered thyristor (LTT), and remains the only manufacturer in the world that can offer commercial LTT.
In 1998, Siemens Semiconductor broke through the development limit of power MOSFETs and launched the CoolMOSTM invention patent, which greatly reduced the drift region Rds (on) of high-voltage power MOSs. Infineon CoolMOS was a milestone in the development history of high-voltage (500V) power MOSFETs.
In 1998, Infineon also introduced a grooved gate low-voltage (150V) power MOSFET, or OptiMOSTM, which significantly reduced the Rds (on) in the channel section. Low Rds (on) is the core competitiveness of Infineon's power MOSFETs.
In 1999, EUPEC introduced the first 6500V IGBT module.
In 1999, Siemens Semiconductor Group went public independently, forming Infineon Technologies.
In 2000, Infineon introduced the trenched gate + field termination technology, the Trench StopTM IGBT3 chip, which is an outstanding combination of the two advanced IGBT chip production technologies available today.