In this era, electronic devices such as mobile phones, computers, laptops, sensors, and many more have become a necessity in healthcare, for a pleasant lifestyle, and for carrying out tasks quickly and easily. Different types of temperature sensors, biosensors, photosensors, etc., have been developed to meet the necessities of people. All these devices have chips inside them fabricated using diodes, transistors, logic gates, and ICs. The patterning of the substrate which is used for the further development of these devices is done with the help of a technique known as lithography. In the present work, we have carried out a review on different types of lithographic techniques such as optical lithography, extreme ultraviolet lithography, electron beam lithography, X-ray lithography, and ion beam lithography. The evolution of these techniques with time and their application in device fabrication are discussed. The different exposure tools developed in the past decade to enhance the resolution of these devices are also discussed. Chemically amplified and non-chemically amplified resists with their bonding and thickness are discussed. Mask and maskless lithography techniques are discussed along with their merits and demerits. Device fabrication at micro and nano scale has been discussed. Advancements that can be made to improve the performance of these techniques are also suggested.

Conducting polymers have been thoroughly investigated and found to have extensive applications in the fields of microwave absorption and electromagnetic (EM) shielding owing to their distinctive characteristics and adaptability. In the present work, conducting polymer (PEDOT and polyaniline) and graphene composites were prepared via an in situ chemical polymerization technique. Further, these composite materials were characterized to determine their potential to address the issue of EM radiation pollution in the microwave frequency (12.4 GHz to 18 GHz). The PEDOT/graphene composites exhibited significant shielding effectiveness of up to 46.53 dB, achieving a green index (g_s) of 1.17. Also, absorption was observed to be the dominant shielding mechanism in all the samples owing to significant dielectric losses (ε′′/ε′ ≈ 1.9–3.1) and microwave conductivity (σ_s = 19.9–73.6 S m⁻¹) in the samples at 18 GHz. Both dielectric loss and conduction loss occurred because of the strong interactions involving polarization, charge propagation, and the creation of conductive routes through the incorporation of graphene in the polymer matrix. These properties/shielding results indicate the potential of the composites to be used as lightweight EM shielding materials. These materials are suitable shield materials for electronic devices to protect them from harmful electromagnetic radiation, making them vital in various applications.

Graphene is the first two-dimensional material that becomes the center material in various research areas of material science, chemistry, condensed matter, and engineering due to its advantageous properties, including larger specific area, lower density, outstanding electrical conductivity, and ease of processability. These properties attracted the attention of material researchers that resulted in a large number of publications on EMI shielding in a short time and play a central role in addressing the problems and challenges faced in this modern era of electronics by electromagnetic interference. After the popularity of graphene, the community of material researchers investigated other two-dimensional materials like MXenes, hexagonal boron nitride, black phosphorous, transition metal dichalcogenides, and layered double hydroxides, to additionally enhance the EMI shielding response of materials. The present article conscientiously reviews the current progress in EMI shielding materials in reference to two-dimensional materials and addresses the future challenges and research directions to achieve the goals.