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Low infrared emissivity coating with good thermal resistance was prepared by using Ni20Cr alloy particles and inorganic silicate as pigments and binders, respectively. The effects of size, shape, and annealing temperature of Ni20Cr alloy particles on infrared emissivity of the coatings were systematically investigated. The results indicate that the composite coatings can exhibit low emissivity (0.49) and good thermal stability property. Ni20Cr alloy particles with tens of micron-sized, flaky, and fine crystal structure can be propitious for decreasing the infrared emissivity of the composite coatings. In addition, the thermal stability properties of the composite coatings were measured in air to explore the effect of high-temperature environment on the infrared emissivity. The measured results show that the composite coatings can exhibit a favorable thermal stability property below 800 °C and still possess low emissivity when the test temperature is below 500 °C, due to the Si–O–Si cross-linking network structure and the mechanical interlocking between the coating and substrate.

Since the environment for the CBM development in China has been changing in recent years, it is necessary to re-consider the relevant strategies. Through investigations, surveys, geologic assessment, strategic decision-making and other techniques, the strategies for CBM development in China were discussed in respect to present situations, opportunities, challenges, proved reserves, producing reserves, strategic principles, strategic countermeasures, time-spatial allocation of strategies, risk assessments, and elimination of relevant risks. Some research results were obtained. Firstly, still in its initial development stage with fast growth, the CBM industry in China has made outstanding achievements in six aspects and also faces challenges in six aspects. Secondly, strategic focus can be summarized as constructing six CBM production bases in Qinshui, Eastern margin of Ordos Basin, Southwest China, Changqing, Northwest China, and Northeast China, respectively, according to the principles of “steadily developing middle-high rank coals, accelerating the development of low-rank coals and strengthening the comprehensive utilization of mining gas wells”. It is expected that the producing reserves and peak-production rate will be 3–4 trillion m3 and 35–45 billion m3/a, respectively. Thirdly, major strategic risks in CBM development in China include low productivities of individual wells, improper understandings of geologic conditions, decline in investments and lack of technical reserves. To eliminate these risks, it is necessary to reinforce work in the following five aspects, namely, strengthening comprehensive exploration and development of coal-bearing formations, creating favorable environments for the development of private oil companies, expanding spaces for the growth of technical service companies, conducting more researches for the development of innovative technologies in more areas and intensifying law enforcement.

At node 28nm and beyond, metal layer have the smallest pitch and the most flexible in design of the critical layer. Various layout patterns on metal layers are challenging to runtime, OPC tools and OPC engineers. The OPC verification played as the role of highlighting fail patterns, and feeding back to the OPC Engineer for further learning and enhancing in the OPC recipe. In this paper the authors presented metal layer OPC repair flow for 28nm node and beyond. An automatic analysis methodology for the pinching, the bridging and the coverage errors were discussed. Next, according to the automated analysis of the error, the OPC repair flow is applied on all locations. This helped in cutting down the total runtime and reached the status of zero errors. This paper also compared the OPC verify result and total runtime of without OPC repair flow and using OPC repair flow. After using OPC repair flow, the OPC verify results are acceptable, and total runtime is reduced greatly.

The microwave absorption property and infrared emissivity have been investigated for the single-layer coating made of the epoxy-polyurethane resin and carbonyl iron powders with variation of annealing treatment. Microwave-absorbing property was investigated by measuring the complex permittivity and complex permeability of the absorber in the frequency range from 2 to 18 GHz. Infrared emissivity value was measured using IR-2 Infrared Emissometer in the wavelength range of 8–14 μm. After annealing, the Fe (110) peak became sharp, and the crystallization improved significantly. Annealing treatment could reduce the surface energy of powders, improve compatibility between fillers and adhesives, and result in increase of the density of the coating. The lowest value of infrared emissivity (0.419) was obtained from the coating made of the carbonyl iron powder annealed at 700°C for 1 h. With the variation of the annealing temperature, the magnetic and dielectric properties of the carbonyl iron particle were changed. The maximum reflection loss decreased and the matching frequency shifted to lower frequency with increasing the annealing temperature of carbonyl iron particles, which coincided with the variation of the complex permeability and permittivity according to the annealing temperature. Magnetic loss factor and dielectric loss factor of carbonyl iron particles were improved with increasing the annealing temperature in the 2–18 GHz range.

At advanced node of metal layer, defocus conditions need to be taken into account in OPC in order to guarantee metal layer process window. Process window OPC (PWOPC) must be considered for the model-based OPC models under special conditions within a lithographic process window. In this paper, we studied several OPC simulation issues in the application of PWOPC in metal layer. The test run results showed that preparatory work and parameters setting were very important for PWOPC application. Without preparatory work or unbefitting parameters setting, the OPC simulation may lead to undesired results. The depth of focus (DOF) of several hot spots was examined. The pinch and bridge error are hot spots while only OPC model under nominal conditions is employed. These hot spots can be resolved while PWOPC models are in consideration. In addition of PWOPC precision study, PWOPC runtime is also evaluated. The use of PWOPC extends OPC runtime at least 50%, which is unacceptable in the environment of longer OPC runtime for the advanced tech node and continuing pull-in tapeout schedule. The runtime speeding up method is studied to reduce the total runtime.

In 28nm technology node, developing an enough lithographic process window of VIA layer became a major challenge in order to meet the requirements of the connectivity between metal lines. It is widely used to size up VIA in order to enlarge VIA process window if the space between VIA holes and VIA enclosed by metal is big enough. But the traditional retarget method has its own limits as the retarget rule table cannot deal with every complex environment for each VIA hole. In this paper, we studied several issues in the application of CALIBRE auto-retarget function in VIA model-based OPC correction after the traditional retarget treatment. The parameters of the auto-retarget function are optimized based on simulated results and the SEM data of the corresponding VIA holes are collected for DOF verification. The impact of the auto-retarget function on model-based OPC runtime is also evaluated. It is shown in the simulation result that the DOF of certain SRAM patterns can be enlarged as much as to 30nm after applying the auto-retarget function. The silicon data confirms the simulation prediction and that the DOF of the patterns become enough for lithographic process. Meanwhile, auto-retarget has little impact on model-based OPC runtime.

With minimum half-pitch shrinking to 28nm, the accuracy requirement imposed on OPC model is getting harder to achieve. In order to meet the much more challenging requirement, uncertainty in the modeling should be diminished as much as possible. The major factors of OPC modeling accuracy consist of OPC model calibration flow, data analysis of mask modeling, lithographic process parameters, and photoresist CD. In this paper, the parameters of mask modeling are analyzed and the mask induced errors are calculated, such as mask bias, mask corner rounding, and mask 3D effect. Furthermore, the interactive relations among these mask parameters are also investigated. A 28nm test model was constructed with optimized mask modeling approaches. The rms of the test model is significantly reduced to half of that of the traditional modeling approaches.

The double-gimbal control moment gyro (DGCMG) demands that the gimbal servosystem should have fast response and small overshoot. But due to the low and nonlinear torsional stiffness of harmonic drive, the gimbal servo-system has poor dynamic performance with large overshoot and low bandwidth. In order to improve the dynamic performance of gimbal servo-system, a model reference adaptive control (MRAC) law is introduced in this paper. The model of DGCMG gimbal servo-system with harmonic drive is established, and the adaptive control law based on POPOV super stable theory is designed. The MATLAB simulation results are provided to verify the effectiveness of the proposed control algorithm. The experimental results indicate that the MRAC could increase the bandwidth of gimbal servo-system to 3 Hz and improve the dynamic performance with small overshoot.