# US 9,041,025 B2 · Monolithic full-color LED micro-display on an Active Matrix panel manufactured using flip-chip technology > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,041,025 B2 - Document ID: US9041025B2 - Status: Granted - Kind: B2 - Application number: 14/098,103 - Filed: 2013-12-05 - Published: 2014-04-03 - Granted: 2015-05-26 - Earliest claimed: 2009-12-09 - Assignees: Nano and Advanced Materials Institute Limited - Applicants: Nano and Advanced Materials Institute Limited - Inventors: Kei May Lau; Zhaojun Liu - Web page: https://patentgrep.com/patent/US9041025B2 ## CPC - G09G 3/32: semiconductive, e.g. using light-emitting diodes [LED] - H05B 45/44: with an active control inside an LED matrix - H10H 29/142: {Two-dimensional arrangements, e.g. asymmetric LED layout} - G09G 2300/0452: Details of colour pixel setup, e.g. pixel composed of a red, a blue and two green components - G09G 2300/0842: forming a memory circuit, e.g. a dynamic memory with one capacitor - H10H 20/8513: {having two or more wavelength conversion materials} - H10H 20/8516: {having a non-uniform spatial arrangement or non-uniform concentration, e.g. patterned wavelength conversion layer or wavelength conversion layer with a concentration gradient} - H10H 20/857: Interconnections, e.g. lead-frames, bond wires or solder balls - H10K 59/1216: {the pixel elements being capacitors} - G09G: ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION (arrangements for transferring data between digital computers and displays G06F3/14; static indicating arrangements comprising an association of a number of separate sources or light control cells G09F9/00; static indicating arrangements comprising integral associations of a number of light sources H01J, H01K, H10H, H05B33/12; scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission, details thereof H04N1/00) - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL - H10H: INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS - H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES ## Abstract A high-resolution, Active Matrix (AM) programmed monolithic Light Emitting Diode (LED) micro-array is fabricated using flip-chip technology. The fabrication process includes fabrications of an LED micro-array and an AM panel, and combining the resulting LED micro-array and AM panel using the flip-chip technology. The LED micro-array is grown and fabricated on a sapphire substrate and the AM panel can be fabricated using PMOS process, NMOS process, or CMOS process. LED pixels in a same row share a common N-bus line that is connected to the ground of AM panel while p-electrodes of the LED pixels are electrically separated such that each p-electrode is independently connected to an output of drive circuits mounted on the AM panel. The LED micro-array is flip-chip bonded to the AM panel so that the AM panel controls the LED pixels individually and the LED pixels exhibit excellent emission uniformity. According to this constitution, incompatibility between the LED process and the PMOS/NMOS/CMOS process can be eliminated. ## Claims ### Claim 1 A Light Emitting Diode (LED) display comprising: an Active Matrix (AM) panel mounted with a plurality of active control circuits, the AM panel having a surface with a plurality of active control circuits mounted so that each active control circuit has a two-transistor-one-capacitor (2T1C) structure, which comprises a first transistor (T1) as a switch transistor, a second transistor (T2) as a driving transistor, and a capacitor (C), a gate electrode of the second transistor (T2) electrically connected to a drain electrode of the first transistor (T1) and an end of the capacitor (C); and a LED panel mounted with a plurality of LEDs arranged in rows and columns; and combined with the AM panel to associate each of the plurality of LEDs with each of the active control circuits, with each pair of an LED and an associated active control circuit electrically insulated from other pairs of LEDs and associated active control circuits in the LED display, and each LED independently controllable by its associated active control circuit. ### Claim 2 (depends on 1) The LED display according to claim 1, wherein each LED includes an n-electrode and a p-electrode, with n-electrodes of the LEDs arranged in rows and conductively connected to a common N-bus line, in turn conductively connected to a ground of the AM panel, and the p-electrode of each LED conductively connected to an output of an associated active control circuit. ### Claim 3 (depends on 1) The LED display according to claim 1, further comprising: a conductive solder connection for connecting the plurality of LEDs with respective ones of the plurality of active control circuits; the LED panel comprising a first substrate, with the plurality of LEDs mounted on the first substrate, the first substrate comprising at least one material selected from the group consisting of: GaAs, SiC, semi-insulating GaAs, sapphire, and quartz; the AM panel comprising a second substrate, with the active control circuits mounted on the second substrate, the second substrate comprising at least one material selected from the group consisting of: single crystal silicon, silicon on insulator (SOI), quartz, and glass; the plurality of the active control circuits on the AM panel comprise circuitry selected from the group consisting of: p-channel Metal Oxide Semiconductor (PMOS) transistor; n-channel Metal Oxide Semiconductor (NMOS) transistor; n-type amorphous silicon Thin Film Transistor (n-type a-Si TFT); p-type amorphous silicon Thin Film Transistor (p-type a-Si TFT); n-type poly crystalline silicon Thin Film Transistor (n-type p-Si TFT); p-type poly crystalline silicon Thin Film Transistor (p-type p-Si TFT); n-type SOI transistor; p-type SOI transistor; zinc oxide TFT; copper oxide TFT; III-V materials TFT; n-channel high electron mobility transistor (n-HEMT); p-channel high electron mobility transistor (p-HEMT); n-channel metal-oxide-semiconductor high electron mobility transistor (n-MOSHEMT); and p-channel metal-oxide-semiconductor high electron mobility transistor (p-MOSHEMT); and the electrical insulation comprises one selected from the group consisting of silicon dioxide, silicon nitride, and high-k materials, formed by thermal growth, low pressure chemical vapor deposition (LPCVD) or plasma enhanced chemical vapor deposition (PECVD), metalorganic chemical vapour deposition (MOCVD), molecular beam epitaxy (MBE), or atomic layer deposition (ALD). ### Claim 4 (depends on 3) The LED display according to claim 3, wherein a first transistor of the two transistors has a connection to a driving signal source and passes therethrough driving signals from the driving signal source to an associated LED responsive to turning ON the first transistor, and a second transistor of the two transistors has a connection to a data signal source and passes therethrough data signals from the data signal source to the first transistor responsive to turning ON the second transistor. ### Claim 5 (depends on 1) The LED display according to claim 1, wherein the plurality of active control circuits mounted on the AM panel comprise circuitry comprising CMOS circuitry. ### Claim 6 (depends on 1) The LED display according to claim 1, further comprising: LEDs arranged in rows and columns; and combined with the AM panel to associate each of the plurality of LEDs with each of the active control circuits to group the LED pixels in groups of four pixels, with the LEDs emitting a single color of light for all pixels; a mold configured to accept phosphors for the individual pixels in each group; phosphors applied to mold at locations corresponding to the individual pixels in each group, with the phosphors transmitting at least 3 primary transmission colors for respective ones of the pixels in each group; phosphors applied to the mold at a locations corresponding to a fourth individual pixel for each group, and transmitting light selected from the group consisting of one of the three primary colors, white light, a non-primary color and a fourth primary color.