Studies Of SOI Materials With New Buried Insulator

Due to the poor thermal conductivity of buried oxide layer, self-heating effect in SOI devices limits the applicability of standard SOI materials. In order to resolve the question and meet the demand of special device/circuit, there has been a strong interest in the development new SOI structures. Replacement of the buried silicon dioxide by a better thermal conductor could minimize the effect effectively. Based on the demands and supports of special Funds for Major State Basic Research projects and the national natural science foundation of china, we have made a series of investigations on fabrication and characterization of new SOI structures (Si-Si3N4-Si substrate, Si-SiO2-Si3N4-Si substrate and Si-SiO2-Si3N4 -Si02-Si substrate), SOG (Silicon-On-Glass) and other new materials. Main newresults are drawn as follows:The properties of SOI materials fabricated by epitaxial layer transfer technology were investigated. Silicon nanorods (about 10-35nm height) on silicon and porous silicon substrates were synthesized using Ultra-high vacuum electron beam evaporation in the present of a Fe catalyst. AFM is used to estimate the dimension and check the morphology of the silicon nanoclusters. The electron field emission is used to reveals the property of silicon nanorods grown on different substrates.SOI structures with Si3N4 film as buried insulator were successfully formed using epitaxial layer transfer technology for the first time. The structural and electrical properties of the new SOI structures were investigated by XTEM and SRP. Due to high stress between the Si/Si3N4 there is a high interface defectAbstractdensity inherent to silicon nitride interface.We have successfully fabricated SOIM structures with SiO2-Si3N4 as buried insulating films using epitaxial layer transfer technology. XTEM and SRP results show the formed SOIM sample has good structural and electrical properties. The oxide layer underneath the thin silicon film can avoid a high interface defect density inherent to silicon nitride interface. The SOIM structures fabricated by this method is a good candidate to be used in micro-electronic and micro-technology applications where thermal effects are to be taken into account, specially when thermal dissipation is needed.The devices based on new SOIM structure has been verified in two-dimensional device simulation and indicated that the new structures reduce device self-heating effect and increase the drain of the SOI MOSFET.It is the first time that we fabricated SOIM structures with SiO2-Si3N4-SiO2 as buried insulating films using Smart-cut technology. XTEM and SRP results show the sample has good structural and electrical properties. The oxide layer between the Si and Si3N4 can avoid a high interface defect density inherent to silicon nitride interface and decrease the bow the wafer.Fabricated monocrystalline SOG (Silicon On Glass) structures by field-assisted bonding technology. The experience results the top silicon has good electrical properties. The integration process of Si and LiTaO3 by Smart-cut technology was created.