Display technologies have continuously evolved since the advent of cathode ray tube (CRT) displays in the early 1900s. Thanks to modern advancements, current display thicknesses are on the order of centimeters and their area has increased 10-fold. Modern flat panel display (FPD) systems consist of a TFT backplane that controls the filtering of a backlight or the modulation of emissive devices such as OLED or microLEDs (µLEDs). MicroLED technology is favored over organic light-emitting diode (OLED) technology due to its higher brightness, energy efficiency, and longer operational lifetime. Additionally, µLEDs offer small pixel sizes, scalability to large screen sizes, and increased durability compared to OLEDs. While both technologies have their strengths and weaknesses, the choice between them depends on specific application requirements and preferences.The primary focus of this work is the process integration of Indium Gallium Zinc Oxide (IGZO) transistors as a µLED backplane for row/column addressing. A single pixel is composed of a µLED driven by an arrangement of two transistors and a storage capacitor. The pixels are then arrayed on a glass substrate to support active-matrix control of monochrome and full color (RGB) displays from 1x1cm (50 x 50 pixels) up to 7.6 x 7.6 cm (380 x 380 pixels). Optimization of circuit parameters considering size and scan frequency was modeled using existing TFT and µLED electrical device compact models. New process parameters and procedures were determined for the proper integration of µLEDs in an existing TFT fabrication process.Red, green, and blue µLED devices were fabricated at Tyndall National Institute on native substrates and were transferred to TFT pixels using an X-Display MTP-1003 micro-transfer printer. The performance of individual test cells was assessed using an Agilent B1500, revealing a voltage transfer characteristic indicating the ability to modulate and control µLED current. Techniques were investigated for the system integration of the active matrix with control circuitry. Figure 1
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