Discrete Semiconductor Devices, etc.
2020s
2020 : Release of 1/2-inch SXGA InGaAs-Si- stacked visible and short-wavelength infrared light image sensors (Sony)
Sony released a small (1/2-inch) image sensor capable of imaging visible and short-wavelength infrared light (wavelength: 0.4-1.7μm) in May 2020. A back-illuminated InGaAs photodiode array chip (1280x1024 pixels, 5μm pitch) was stacked on a Si CMOS readout circuit chip. The electrodes between the chips were connected by Cu-Cu direct bonding.
Schematic of the cross-sectional structure
SWIR image sensor (IMX990)
Example of imaging
2020 : Commercialization of X-band 300W output GaN HEMTs (Sumitomo Electric Industries)
Sumitomo Electric Industries has commercialized a 300W-class AlGaN/GaN on SiC HEMT for X-band (9GHz band) radars equipped on ships and other marine vessels. At an operating voltage of 50 V, the device achieved the world's highest level of high performance with an output power of 340 W, gain of 9.3 dB, and power added efficiency of 38% at the condition of pulse operation (pulse width of 100 µs and duty cycle of 10%).
2021 : Development of 10W-class high-power blue semiconductor laser diode (Nichia)
Nichia has developed a high-power GaN-based semiconductor blue laser diode that emits 11.2 W of blue light (wavelength: 455 nm), the world's highest optical output per emitter stripe.
Fabrication process of free-standing GaN single-crystal substrates
Free-standing GaN single-crystal substrates
High output blue LD
2022 : Development of terahertz device using resonant tunnel diode (RTD) (Canon)
Canon has developed a terahertz wave oscillating device with an output power of approximately 12 mW at a frequency of 450 GH by monolithically integrating 6x6(36) double-resonant-tunneling-diode patch-antennas and synchronously operating all antennas.
Cross-sectional structure of a resonant tunnel diode
RTD band structure
RTD-based THz source
2022 : Launch of SPAD direct ToF method depth sensor for automotive LiDAR (Sony)
Sony launched a SPAD（Single Photon Avalanche Diode）direct ToF (Direct Time of Flight) method depth sensor for automotive LiDAR (Light Detection and Ranging), in which a back-illuminated SPAD pixel chip and a logic chip integrating signal processing circuits were stacked with Cu-Cu (copper-copper) connection. Micro-lenses and concavo-convexities on the light input surface increased the incident light absorption, achieving a high Photon Detective Efficiency (PDE) of 24% for light at wavelength of 905nm. It enabled high-speed, high-precision distance measurement with resolutions of 15cm from distance of 200m to close range.
Schematic of LiDAR system
I-V characteristics of SPAD and photon counting operation
SPAD Photodetector circuit and operating waveforms
2023 : Development of a wider-temperature-range 100 Gbps Electro-absorption Modulator integrated Laser (EML) for data centers (Mitsubishi Electric)
Mitsubishi Electric has developed an Electro-absorption Modulator integrated Laser (EML) operating at communication speed of 100 Gbps over a wide chip temperature range between 5℃ and 85℃. 400 Gbps optical transceivers for data centers can be realized by four-wavelength multiplexing without temperature control TEC.
Schematic of the structure of EML
Cross-sectional structure of EML element
Electro-absorption Modulator integrated Laser (EML)
