Two-dimensional semiconductor materials, represented by transition metal dichalcogenides (TMDCs), have the characteristics of extreme thickness, high mobility, and back-end heterogeneous integration. They are expected to continue Moore's law and realize integrated circuits with three-dimensional architecture. and industry attention. After nearly a decade of development, two-dimensional electronics has made great progress, but there are still challenges in the preparation of large-area single crystals, key device processes, and compatibility with mainstream semiconductor technologies.
Il-grupp ta 'riċerka tal-Prof. Xinran Wang mill-Iskola tax-Xjenza u l-Inġinerija Elettronika tal-Università ta' Nanjing iffoka fuq il-problemi ta 'hawn fuq u rriċerka skoperti fit-teknoloġiji ewlenin ta' fabbrikazzjoni ta 'kristall wieħed semikondutturi b'żewġ -dimensjonijiet u etero- integrazzjoni, li pprovdiet ideat ġodda għall-iżvilupp ta' ċirkwiti integrati fl-era ta' wara-Moore. Riżultati ta' riċerka rilevanti ġew ippubblikati f'Nature Nanotechnology dan l-aħħar.
Building "atomic terraces" down-to-earth, breaking through two-dimensional semiconductor single crystal epitaxy
Materjali tal-kristall wieħed semikondutturi huma l-pedament tal-industrija tal-mikroelettronika. Meta mqabbel mal-wejfers tas-silikon monokristallin ta '12-pulzier mainstream, il-preparazzjoni ta' semikondutturi bi-dimensjonali għadha fl-istadju ta 'skala żgħira-u polikristallina. L-iżvilupp ta' films irqaq monokristallini ta'-erja kbira, ta'-kwalità għolja huwa l-ewwel pass lejn ċirkwiti integrati bi-dimensjonali. . Madankollu, matul it-tkabbir ta 'materjali bi-dimensjonali, miljuni ta' ċipep mikroskopiċi huma ġġenerati b'mod każwali, u huwa possibbli biss li jinkiseb materjal monolitiku ta 'kristall wieħed billi tikkontrolla ċ-ċipep kollha biex tinżamm direzzjoni ta' arranġament strettament konsistenti.
Sapphire is a widely used substrate in the semiconductor industry and has outstanding advantages in mass production, low cost and process compatibility. The collaborating team proposed a scheme to artificially construct atomic-scale "terraces" by changing the direction of the atomic steps on the sapphire surface. The directional growth of TMDCs was achieved by the directional induced nucleation mechanism of "atomic terraces".
Based on this principle, the team achieved the epitaxial growth of a 2-inch MoS2 single crystal film for the first time in the world. Thanks to the improvement of material quality, the mobility of field effect transistors based on MoS2 single crystal is as high as 102.6 cm2/Vs, and the current density reaches 450 μA/μm, which is one of the highest comprehensive performances reported internationally. At the same time, the technology has good universality and is suitable for the preparation of single crystals of other materials such as MoSe2. This work has laid a material foundation for the application of TMDC in the field of integrated circuits.
Meta wieħed iħares 'il fuq lejn l-istilel, is-semikondutturi bi-dimensjonali jġibu d-dawl għat-teknoloġija tal-wiri tal-futur
L-avvanz ta' materjali ta' kristall wieħed ta'-erja kbira- jagħmilha possibbli li jiġu applikati semikondutturi bi-dimensjonali. Fit-tieni xogħol, ibbażat fuq snin ta 'akkumulazzjoni ta' riċerka ta 'semikondutturi tat-tielet -ġenerazzjoni, flimkien mal-aħħar soluzzjoni ta' kristall wieħed semikondutturi bi -dimensjonali, it-tim kooperattiv tal-Iskola tal-Electronics ippropona ultra monolitiku integrat -Display tal-Mikro LED b'riżoluzzjoni-għolja bbażata fuq iċ-ċirkwit tas-sewwieq tat-transistor tal-film irqiq MoS2. Soluzzjonijiet tekniċi.
Mikro LED tirreferi għal teknoloġija li tuża LEDs fuq skala micron- bħala unitajiet ta 'pixels li jarmu d-dawl- u tiġborhom b'moduli tas-sewqan biex jiffurmaw firxa ta' wiri ta'-densità għolja. Meta mqabbel mat-teknoloġiji tal-wiri mainstream attwali bħal LCD u OLED, Micro LED għandu vantaġġi trans-ġenerazzjonali f'termini ta 'luminożità, riżoluzzjoni, konsum ta' enerġija, ħajja tas-servizz, veloċità ta 'rispons u stabbiltà termali, u huwa rikonoxxut internazzjonalment li jmiss{ {4}}teknoloġija tal-wiri tal-ġenerazzjoni.
Madankollu, l-industrijalizzazzjoni tal-Mikro LED għadha tiffaċċja ħafna sfidi. L-ewwel, huwa diffiċli li tqabbel ir-rekwiżiti tas-sewqan ta 'unitajiet tal-wiri ta'-densità għolja f'daqsijiet żgħar. It-tieni nett, it-teknoloġija tat-trasferiment tal-massa popolari fl-industrija hija diffiċli biex tissodisfa l-ħtiġijiet ta 'żvilupp ta' wirjiet ta '-riżoluzzjoni għolja f'termini ta' spiża u rendiment. Speċjalment għal applikazzjonijiet ta 'riżoluzzjoni ultra-għolja- bħal AR/VR, mhux biss ir-riżoluzzjoni hija meħtieġa li taqbeż it-3000PPI, iżda wkoll il-pixels tal-wiri jeħtieġ li jkollhom frekwenza ta' rispons aktar mgħaġġla.
The cooperative team aimed at the field of high-resolution micro-display, and proposed a technical solution for the 3D monolithic integration of MoS2 thin-film transistor driver circuit and GaN-based Micro LED display chip. The team developed a non-"massive transfer" low-temperature monolithic heterogeneous integration technology, using a nearly non-destructive large-size two-dimensional semiconductor TFT manufacturing process, to achieve a high-brightness, high-resolution microdisplay of 1270 PPI, which can meet the needs of future microdisplays. Display, vehicle display, visible light communication and other cross-field applications.
Among them, compared with the traditional two-dimensional semiconductor device process, the new process developed by the team improves the performance of thin film transistors by more than 200 percent , reduces the difference by 67 percent , and the maximum driving current exceeds 200 μA/μm, which is better than IGZO, LTPS and other commercial materials. It shows the huge application potential of two-dimensional semiconductor materials in the display driving industry. This work is the first in the world to integrate two emerging technologies of high-performance two-dimensional semiconductor TFT and Micro LED, which provides a new technical route for the future development of Micro LED display technology.
The above works are respectively named "Epitaxial growth of wafer-scale molybdenum disulfide semiconductor single crystals on sapphire" (corresponding authors are Prof. Wang Xinran and Prof. Wang Jinlan of Southeast University) and "Three dimensional monolithic Micro LED display driven by atomically-thin transistor matrix" (corresponding authors). It was published online in Nature Nanotechnology recently.
This series of work has been supported by projects such as Jiangsu Province's Frontier Leading Technology Basic Research Project, the National Natural Science Foundation of China, and the National Key RD Program. Changchun Institute of Optics and Mechanics, Chinese Academy of Sciences, Tianma Microelectronics Co., Ltd., Nanjing Huanxuan Semiconductor Co., Ltd., etc.
