Post-doping plasma for DRAM capacitors
Researchers from Ulsan National Institute of Science and Technology (UNIST), Pohang University of Science and Technology (POSTECH), and Seoul National University of Science and Technology developed a post-doping plasma (PDP) course of to enhance the efficiency of DRAM capacitors.
Aluminum-doped titanium dioxide (Al-doped TiO2) is a promising materials for the DRAM capacitor’s dielectric layer as a result of its excessive dielectric fixed and wonderful leakage suppression, however typical atomic layer deposition (ALD) fabrication strategies could cause lattice dysfunction and oxygen vacancies, resulting in materials instability and elevated leakage currents.
To overcome this, the PDP course of entails first depositing the TiO2 dielectric layer by way of ALD and subsequently coating it with an ultrathin aluminum oxide layer, then exposing the movie to a plasma composed of argon and oxygen. The plasma therapy transfers power to the movie’s floor, facilitating atomic-scale migration of aluminum dopants and reordering of the crystal lattice whereas concurrently filling oxygen vacancies.
The workforce discovered that DRAM capacitors handled with the PDP course of exhibited roughly 30% larger dielectric constants and as much as practically 40 occasions decrease leakage currents. The strategy has potentialities past DRAM, too, stated Jihwan An, a professor at POSTECH, in an announcement. “The atomic-layer process developed in this study can be applied broadly—not only to DRAM but also to next-generation electronic devices and energy storage systems.” [1]
Superconducting germanium
Researchers at New York University and University of Queensland produced a superconducting form of germanium.
The workforce used molecular beam epitaxy to dope the germanium with excessive ranges of gallium whereas retaining the soundness of its crystal construction. “Rather than ion implantation, molecular beam epitaxy was used to precisely incorporate gallium atoms into the germanium’s crystal lattice,” stated Julian Steele, a physicist on the University of Queensland, in a press launch. “Using epitaxy—growing thin crystal layers—means we can finally achieve the structural precision needed to understand and control how superconductivity emerges in these materials.”
The doped germanium was capable of conduct electrical energy with zero resistance at 3.5 Kelvin. “These materials could underpin future quantum circuits, sensors, and low-power cryogenic electronics, all of which need clean interfaces between superconducting and semiconducting regions,” stated Peter Jacobson, a physicist on the University of Queensland, in a press launch. “Germanium is already a workhorse material for advanced semiconductor technologies, so by showing it can also become superconducting under controlled growth conditions there’s now potential for scalable, foundry-ready quantum devices.” [2]
Making n-type polymer semiconductors
Researchers from Pohang University of Science and Technology (POSTECH) and Sungkyunkwan University discovered that adjusting the focus of a single dopant allows versatile natural polymer semiconductors to modify from p-type to n-type.
Most conjugated polymers naturally exhibit p-type habits, however for sensible functions, a single polymer system ought to exhibit each p-type and n-type traits to eradicate the necessity for separate supplies or complicated multilayer gadget architectures.
By doping a usually p-type polymer with a sufficiently excessive focus of gold(III) chloride (AuCl3), the dominant cost carriers shift from holes to electrons. In investigating the underlying habits, the workforce discovered that the oxidation states of gold and chloride ions evolve throughout doping, resulting in a substitutional chlorination response with the polymer chains that induces structural reordering of the polymer spine, realigning the molecular construction and reorganizing cost transport pathways.
The researchers used the strategy to manufacture a p–n natural homojunction diode utilizing a single polymer doped at two completely different concentrations that exhibited a rectification ratio tens of hundreds of occasions larger than typical single-material natural diodes. They famous that the strategy exhibits potential to allow high-performance, versatile digital gadgets with simplified architectures. [3]
References
[1] G. Lee, Y. Sunwoo, H. J. Kim, et al. In-situ post-doping plasma course of throughout atomic layer deposition of Al-doped TiO2 for sub-nanometer lattice ordering and defect annihilation. Int. J. Extrem. Manuf. 8 015101 https://dx.doi.org/10.1088/2631-7990/ae037b
[2] J.A. Steele, P.J. Strohbeen, C. Verdi, et al. Superconductivity in substitutional Ga-hyperdoped Ge epitaxial skinny movies. Nat. Nanotechnol. (2025). https://doi.org/10.1038/s41565-025-02042-8
[3] E. Ok, S. Chung, S. H. Kim, et al. Accompanying Structural Transformations in Polarity Switching of Heavily Doped Conjugated Polymers. Adv. Mater. 37, no. 39 (2025): 37, 2505945. https://doi.org/10.1002/adma.202505945
Jesse Allen
Jesse Allen is the Knowledge Center administrator and a senior editor at Semiconductor Engineering.