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This study compares the capacitance–voltage (C–V) characteristics in silicon–germanium (SiGe) metal-oxide-semiconductor capacitances with and without a silicon oxide capping layer. The SiGe channel with the silicon oxide capping layer exhibits an improved C–V property at room temperature but has an abnormal shift and depression at low temperature (77 K). We determined that the threshold voltage shift was induced by the Fermi-level when ambient temperature was changed. The additional silicon capping layer was responsible for introducing defects resulting in depression and hump in the C–V measurements. Such a phenomenon is mainly caused by the different distribution of defects, which was established by modifying the alternating current pulse amplitude during the C–V measurement. [ABSTRACT FROM AUTHOR]

This paper studies a composite device composed of ferroelectric random access memory (FeRAM) and metal-oxide-semiconductor field effect transistor. The relationship between the hysteresis characteristics and VG is reported, and the on/off ratios under different writing voltages are presented. The gm–VG curve of the forward and reverse sweeping shows that under forward sweep a very clear instability appears while voltage increases. The reasons for this can be explained according to the voltage divider rule, the ID formula, and gm formula of transistors, which show that there is polarization of the ferroelectric material. Accordingly, a method is proposed to determine the critical point of the ferroelectric capacitor polarization in this 1T1C structure, which is advantageous because it identifies the appropriate reading voltage necessary for an effective program state of the 1T1C device. This method was shown in three 1T1C and three FeRAMs devices with different ferroelectric areas. Finally, this method was verified by the P–V loop of FeRAMs. [ABSTRACT FROM AUTHOR]

This work investigates a low-temperature and high-pressure (LTHP) hydrogen treatment in Si-channel and SiGe-channel metal–oxide–semiconductor capacitors (MOSCAPs). The LTHP hydrogen treatment can repair dangling bonds in the SiO2/Si and SiO2/SiGe interfaces to enhance device performance. Additional parameters of the treatment, including treatment pressure and time, are also investigated to better understand the reaction mechanisms, which further proves the effectiveness and potential of this supercritical fluid (SCF)-based treatment. In addition, this treatment will not damage the front structure and materials due to the relatively low process temperature (120 °C). Therefore, this treatment can be a nondestructive postannealing process. The results of extracting interface defect density (Dit) by the conductance method show that there is an ~51% reduction in the defect density after this posttreatment, a significant decrease. Finally, a TCAD simulation of different defect densities verifies the repair mechanism of deep-level defects. [ABSTRACT FROM AUTHOR]

This work investigates the effects of HfO2 layer defects, formed by the Al atoms in the metal gate, on performance and reliability in advanced n-type metal–oxide–semiconductor field-effect transistors (n-MOSFETs) with different Al content in the gate stacks. Many groups have proposed theories (e.g., Si–H bond dissociation, trapped in high- ${k}$ defects and impact ionization) to explain the degradation mechanisms in MOSFETs, with most focusing on the dissociation of the Si-H bond at the Si/SiO2 interface and the carrier trapping in the high- $k$ layer. However, for multi- ${V}_{{\text {th}}}$ devices, experimental results indicate that the formation of defects by Al atoms in the HfO2 layer is the main reason for degradation in advanced n-MOSFETs. Therefore, we propose a mechanism to clarify the deterioration in advanced n-MOSFETs with different Al content in the gate stacks, and this mechanism is confirmed by positive bias temperature instability (PBTI), hot carrier instability (HCI), HCI power-law fitting and the gate-induced drain leakage (GIDL) measurement. [ABSTRACT FROM AUTHOR]