Wide range detector of plasma induced charging effect for advanced CMOS BEOL processes

This work proposed a modified plasma induced charging (PID) detector to widen the detection range, for monitoring the possible plasma damage across a wafer during advanced CMOS BEOL processes. New antenna designs for plasma induced damage patterns with extended capacitors are investigated. By adapting the novel PID detectors, the maximum charging levels of the detectors have been enhanced.

Room-Temperature Solution-Processed 0D/1D Bilayer Electrodes for Translucent CsPbBr3 Perovskite Photovoltaics

Materials and processing of transparent electrodes (TEs) are key factors to creating high-performance translucent perovskite solar cells. To date, sputtered indium tin oxide (ITO) has been a general option for a rear TE of translucent solar cells. However, it requires a rather high cost due to vacuum process and also typically causes plasma damage to the underlying layer. Therefore, we introduced TE based on ITO nanoparticles (ITO-NPs) by solution processing in ambient air without any heat treatment. As it reveals insufficient conductivity, Ag nanowires (Ag-NWs) are additionally coated. The ITO-NPs/Ag-NW (0D/1D) bilayer TE exhibits a better figure of merit than sputtered ITO. After constructing CsPbBr3 perovskite solar cells, the device with 0D/1D TE offers similar average visible transmission with the cells with sputtered ITO. More interestingly, the power conversion efficiency of 0D/1D TE device was 5.64%, which outperforms the cell (4.14%) made with sputtered-ITO. These impressive findings could open up a new pathway for the development of low-cost, translucent solar cells with quick processing under ambient air at room temperature.

Investigation of Normally-Off p-GaN/AlGaN/GaN HEMTs Using a Self-Terminating Etching Technique with Multi-Finger Architecture Modulation for High Power Application

Normally-off p-gallium nitride (GaN) high electron mobility transistor (HEMT) devices with multi-finger layout were successfully fabricated by use of a self-terminating etching technique with Cl2/BCl3/SF6-mixed gas plasma. This etching technique features accurate etching depth control and low surface plasma damage. Several devices with different gate widths and number of fingers were fabricated to investigate the effect on output current density. We then realized a high current enhancement-mode p-GaN HEMT device with a total gate width of 60 mm that exhibits a threshold voltage of 2.2 V and high drain current of 6.7 A.

In-Situ Repair Plasma-Induced Damage and Cap Dielectric Barrier for Porous Low-Dielectric-Constant Materials by HMDS Plasma Treatment

Plasma damage and metal ion penetration are critical issues for porous low-dielectric-constant (low-k) materials used in the back-end-of-line interconnects. This study proposed a novel process with in-situ repairing plasma-induced damage and capping a barrier for porous low-k materials by Hexamethyldisilazane (HDMS) plasma treatment. For a plasma-damaged porous low-k material, its surface hydrophilic state was transformed to hydrophobic state by HDMS plasma treatment, revealing that damage was repaired. Simultaneously, a dielectric film was capped onto the porous low-k material, and displayed better barrier capability against Cu migration. Additionally, the breakdown reliability of the stacked dielectric was enhanced by the means of HDMS plasma treatment. The optimized HDMS plasma treatment time was found to be 10 s. Therefore, this proposed HDMS plasma treatment processing is a promising technique for highly applicable low-k material used for advanced technology nodes.

Enhancement in external quantum efficiency of AlGaInP red μ-LED using chemical solution treatment process

To investigate the effects of their surface recovery and optical properties, extremely small sized (12 µm × 12 µm mesa area) red AlGaInP micro light emitting diodes ($$\upmu$$ μ LED) were fabricated using a diluted hydrofluoric acid (HF) surface etch treatment. After the chemical treatment, the external quantum efficiencies (EQEs) of $$\upmu$$ μ -LED at low and high injection current regions have been improved by 35.48% and 12.86%, respectively. The different phenomena of EQEs have a complex relationship between the suppression of non-radiative recombination originating from the etching damage of the surface and the improvement of light extraction of the sidewalls. The constant enhancement of EQE at a high injection current it is attributed to the expansion of the active region’s sidewall surface area by the selective etching of AlInP layers. The improved EQE at a low injection current is related to the minimization of the surface recombination caused by plasma damage from the surface. High-resolution transmission electron microscopy (HR-TEM) revealed physical defects on the sidewall surface, such as plasma-induced lattice disorder and impurity contamination damage, were eliminated using chemical treatment. This study suggests that chemical surface treatment using diluted HF acid can be an effective method for enhancing the $$\upmu$$ μ -LED performance.

Wide Range Detector of Plasma Induced Charging Effect for Advanced CMOS BEOL Processes

This work proposed a modified plasma induced charging recorder to widen detection range, for monitoring the possible plasma damage across a wafer during advanced CMOS BEOL processes. New antenna designs for plasma induced damage patterns with extended capacitance are investigated. By adapting the novel PID recorders, maximum charging levels of the detectors have been enhanced.

Effects of Plasma Damage Removal on Direct Contact Resistance and Hot-Electron-Induced Punch Through (HEIP) of PMOSFETs

In order to reduce contact resistance (Rc) of the source/drain region in nanoscale devices, it is essential to overcome the increasing leakage and hot-electron-induced punch through (HEIP) degradation. In this paper, we propose a simple in situ Si soft treatment technique immediately after direct contact (DC) etching to reduce Rc and minimize HEIP degradation. We found by analysis with a transmission electron microscope, that 10 s of treatment reduced the plasma damaged layer by 19%, which resulted in 10.5% reduction of the P+ contact resistance. For comparison, the P + Rc was reduced by 6.5% when the doping level of the plug implantation was increased by 25%, but the HEIP breakdown voltage (VHEIP) by AC stress was greatly reduced by more than 80 mV, increasing the standby leakage current of DRAM devices. In the case of removing the plasma damage layer, not only did VHIEP not decrease until after 10 s, but also the reduction in Rc was larger than with the plug enhancement. The effect of the plasma damaged layer on HEIP was verified through the plug effect and gate induced drain leakage measurement, based on the distance between the gate and DC for each process. This simple in situ technique not only removed byproducts and the plasma damaged amorphous layer, but it also affected the effective implantation of dopants in subsequent plug processes. It was also cost effective because the process time was short and no extra process steps were added.

Effect of Magnetic Field Arrangement of Facing Targets Sputtering (FTS) System on Controlling Plasma Confinement

Conventional sputtering method uses a single cathode with a permanent magnet. Facing targets sputtering (FTS) methods consists of two cathodes. Because of a unique structure, FTS can prepare high quality films with low temperature and low plasma damage. During the film sputtering process, density and confinement of discharged plasma depend on the arrangement of a permanent magnet in the cathode. In this study, we designed two types of permanent magnet arrangements in the FTS system and the designed permanent magnet was inserted into two cathodes in the FTS system. The system was operated in different permanent magnet conditions, and their discharge voltage and properties of as-grown films were recorded. In the designed FTS, compared to a conventional magnetron sputtering method, the substrate temperature increased to a value under 80 °C, which is relatively low, even though the films’ sputtering process was completed.