This paper reports a novel full logic compatible 4T2R non-volatile static random access memory (nv-SRAM) featuring its self-inhibit data storing mechanism for in low-power/high-speed SRAM application. With compact cell area and full logic compatibility, this new nv-SRAM incorporates two STI-ReRAMs embedded inside the 4T SRAM. Data can be read/write through a cross-couple volatile structure for maintaining fast accessing speed. Data can be non-volatilely stored in new SRAM cell through a unique self-inhibit operation onto the resistive random access memory (RRAM) load, achieving zero static power during data hold.

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The reflected image on the surface of the fiber-reinforced plastic (FRP) often presents twists and wrinkles. This phenomenon is called print-through phenomenon (PTP) in this investigation and the lines present on the material surface are called print-through lines (PTL). Earlier studies and experimental observations indicate that PTP is related to the non-uniform inner stress in the gel coating layer of the FRP. The non-uniform inner stress is caused by the various shrinkages of the plastic matrix and fibers of the fiber layers during the laminating process. So the main idea to reduce PTP is to reduce or uniform the non-uniform inner stress in the gel coating layer of the FRP. Several methods can be used to reduce PTP and two of them are investigated in this paper. One is removing atmospheric pressure before the plastic matrix of the fiber layers hardens. The other method is inserting a core-Mat layer into the Mat layers during laminating the FRP.Removing atmospheric pressure before the plastic matrix hardens can remove the influence of atmospheric pressure on causing the inner stress of the gel coating layer. Once the inner stress of the gel coating layer is reduced, PTP on the surface of the FRP can be eased off. Inserting a core-Mat layer into the Mat layers will form a buffer zone which can uniform the inner stress in the gel coating layer of the FRP. Therefore, PTP on the surface of the FRP can be eased off. To verify the present contentions, some experiments and qualitative analysis were performed. Both experimental and analysis results show that the PTP on the surface of FRP can be reduced by the present methods.

Unsaturated polyester filled with coloring agent is commonly used as the surface material of a GFRP yacht and is called a gel-coating layer. The reflection on the gel-coating layer surface will be imperfect if twists and wrinkles exist on the gel-coating surface. This phenomenon is called print-through phenomenon (PTP) in this investigation. The PTP seriously reduces the beauty of a yacht and therefore limits the application of GFRP to the yacht. Therefore, it is urgent to solve the PTP problem. The first goal of this study is to objectively define and quantitatively measure the existence of PTP and its level. The surface of the gel-coating layer of GFRP is scanned by using the portable high resolution surface roughness and form measurement instrument. Based on a large number of experiments, the average parameter, arithmetic mean deviation (R a ), and the peak parameter, the altitude of the surface profile (R t ), are proposed to determine the existence of PTP and its level. The second goal of this study is to consider the causes of PTP happening and find out the factors that can influence it. Through experimental observations and qualitative analysis, it is believed that PTP is related to the non-uniform residual stress in the gel-coating layer of GFRP. So, any factors which can produce the non-uniform residual stress in the gel-coating layer can influence PTP, such as the shrinkage of the resin during its hardening chemical reaction and the atmospheric pressure during the Seemann composite resin infusion molding process (SCRIMP). After ascertaining what causes PTP, research methods that can be used to reduce PTP will then be studied.

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Highly selective wet etching of GaAs on Al0.2Ga0.8As can be realized using citric buffer (citric acid/H2O2/H2O) solutions. The selectivity can be up to 256, which is distinct from the previous non-selectivity inference, due to consulting the role of H2O2 in this etching system. The etch stop mechanism is demonstrated by X-ray photoelectron spectroscopy (XPS) and indicates the formation of dense oxide Al2O3 on Al0.2Ga0.8As to stop etching. The applications to pseudomorphic high electron mobility transistors (PHEMT) gate recess processes, no obvious drain current decrease can be perceived even after 8 min overetching. The etched surface is very smooth with the roughness of only 1.97 Å. The devices also show excellent etched uniformity with a small threshold voltage deviation of 28 mV and good electrical performance, which is useful to the heterostructure device fabrications.

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Selective area epitaxial (SAE) growth of strained SiGe:B (Boron) in the recessed source/drain (S/D) region of an MOS device is known to improve Si-PMOS performance due to enhancement of hole mobility and reduction of S/D resistance. However, the process may be adversely affected by pattern loading effects, SiGe relaxation, dislocation formation, dopant precipitation and contamination. These effects, if not controlled, will deteriorate device performance and yield. A nondestructive, in-line SAE process monitoring approach on patterned wafers is especially desired. A specialized, contact-less, carrier lifetime-based Room Temperature -Photoluminescence (RT-PL) method meets this demand. The RT-PL tool, which uses a novel excitation path design to achieve carrier confinement, device-suitable probing depth, submicron scanning resolution and a micron probe size, offers a quick, non-destructive assessment of strain, defects and contamination for SAE. In this paper, a systematic evaluation of blanket and selective growth layers is illustrated using layers with a Ge content of 15-25%, undoped and B-doped at ~10 20 cm -3 concentration. For the as-grown conditions, we observed that SiGe remains in an unrelaxed state without extended dislocations being formed. These results suggest that SiGe composition could be further modified to optimize the associated mobility enhancement. Uniformity variations associated with SiGe composition and B-doping were identified. Excessive boron precipitation, metallic particle-originated defects and large contamination regions induced by processing tools were also exposed. The multiple and unique insights enabled through the RT-PL technique provide significant benefits towards decreasing process development and integration time, maintaining SiGe process in control and reducing device fabrication costs.