Silicone engineered anisotropic lithography for ultrahigh-density OLEDs

Abstract

Ultrahigh-resolution patterning with high-throughput and high-fidelity is highly in demand for expanding the potential of organic light-emitting diodes (OLEDs) from mobile and TV displays into near-to-eye microdisplays. However, current patterning techniques so far suffer from low resolution, consecutive pattern for RGB pixelation, low pattern fidelity, and throughput issue. Here, we present a silicone engineered anisotropic lithography of the organic light-emitting semiconductor (OLES) that in-situ forms a non-volatile etch-blocking layer during reactive ion etching. This unique feature not only slows the etch rate but also enhances the anisotropy of etch direction, leading to gain delicate control in forming ultrahigh-density multicolor OLES patterns (up to 4500 pixels per inch) through photolithography. This patterning strategy inspired by silicon etching chemistry is expected to provide new insights into ultrahigh-density OLED microdisplays.

Wafer-scale lithography of silicone-integrated hole transporters for anti-pixel crosstalk organic light-emitting diodes

“…The PEDOT:PSS was spin-coated at 4,000 rpm for 1 min onto SiO 2 or ITO/glass substrate and was annealed at 120 ℃ for 1 h. A solution of SI-HTL was prepared by dissolving the QUPD (10 mg/ml in CB) ≥ and the silicone crosslinkers (4, 8, 16 mol% relative to QUPD), and was mixed at 100 ℃ for 2 h. After mixing, the solution was spin-coated at 2,000 rpm for 1 min onto the prepared PEDOT:PSS coated substrate, and then the resulting lm was annealed at 180 for 3 h in N 2 environment. During annealing process, the oxetane ring-opening reaction was activated by protonation from the underlying PEDOT:PSS or OPPI 42,43 , and concurrently, the sol-gel reaction between the silicone crosslinkers was driven by the thermal energy 14,29 . The thickness of the lms was measured by a surface pro lometer (Bruker, Dektak XT-E) and AFM (Park systems, NX10).…”

“…7). This retards the chemical etching-induced reduction in molecular weight, which could affect the lm modulus 14,33 . As shown in Fig.…”

“…Notably, the scalability of the FMM has advanced signi cantly, achieving resolutions of up to 3,000 ppi 11 . Nevertheless, persistent challenges encompass manufacturing yield, throughput concerns, and mask deformation which impact reusability and pattern accuracy [12][13][14] . In response to these challenges, alternative techniques such as transfer printing [15][16][17] , inkjet printing 18,19 , and template growth 20,21 have emerged (Supplementary Table 1).…”

Thermal Dehydrogenation Impact on Positive Bias Stability of Amorphous InSnZnO Thin-Film Transistors

“…13,14 However, for UHR display panels intended for head-mounted display applications, at least 3000 PPI or higher pixel density is required. 12,15 Therefore, there is a growing demand for oxide semiconductor TFTs that not only exhibit low off-current characteristics but also possess a higher mobility and stable bias stability. In addition, during the fabrication process of LTPO, concerns arise regarding the degradation of electrical performance and bias stability in oxide semiconductors due to the inflow and outflow of hydrogen resulting from the LTPS passivation and gate insulator deposition processes.…”

“…While LTPS TFTs are advantageous for achieving high refresh rates due to their high carrier mobility, the drawback of LTPS TFTs is that signals should be sent at a minimum rate of 60 Hz to prevent luminance reduction and flickering caused by a high leakage current. Combining LTPS TFTs with AOS TFTs makes it possible to achieve both high refresh rates and low leakage current, making LTPO a promising driving method for UHR displays. , However, for UHR display panels intended for head-mounted display applications, at least 3000 PPI or higher pixel density is required. , Therefore, there is a growing demand for oxide semiconductor TFTs that not only exhibit low off-current characteristics but also possess a higher mobility and stable bias stability. In addition, during the fabrication process of LTPO, concerns arise regarding the degradation of electrical performance and bias stability in oxide semiconductors due to the inflow and outflow of hydrogen resulting from the LTPS passivation and gate insulator deposition processes. ,, Hydrogen plays a dual role in oxide semiconductors, passivating interface defects, , oxygen vacancies, and weakly bonded states while also generating hydroxyl-related defects and simultaneously causing the formation of oxygen vacancies and donor-like defects, which results in excessive carrier and threshold voltage shift .…”