3D Printed Quantum Dot Light-Emitting Diodes

Abstract

Developing the ability to 3D print various classes of materials possessing distinct properties could enable the freeform generation of active electronics in unique functional, interwoven architectures. Achieving seamless integration of diverse materials with 3D printing is a significant challenge that requires overcoming discrepancies in material properties in addition to ensuring that all the materials are compatible with the 3D printing process. To date, 3D printing has been limited to specific plastics, passive conductors, and a few biological materials. Here, we show that diverse classes of materials can be 3D printed and fully integrated into device components with active properties. Specifically, we demonstrate the seamless interweaving of five different materials, including (1) emissive semiconducting inorganic nanoparticles, (2) an elastomeric matrix, (3) organic polymers as charge transport layers, (4) solid and liquid metal leads, and (5) a UV-adhesive transparent substrate layer. As a proof of concept for demonstrating the integrated functionality of these materials, we 3D printed quantum dot-based light-emitting diodes (QD-LEDs) that exhibit pure and tunable color emission properties. By further incorporating the 3D scanning of surface topologies, we demonstrate the ability to conformally print devices onto curvilinear surfaces, such as contact lenses. Finally, we show that novel architectures that are not easily accessed using standard microfabrication techniques can be constructed, by 3D printing a 2 × 2 × 2 cube of encapsulated LEDs, in which every component of the cube and electronics are 3D printed. Overall, these results suggest that 3D printing is more versatile than has been demonstrated to date and is capable of integrating many distinct classes of materials.

3D printed optics with nanometer scale surface roughness

“…Additive manufacturing and three-dimensional (3D) printing have improved access to and flexibility of highquality fabrication technology with profound impact on a number of industries 1 , including automotive, electronics [2][3][4] , aerospace, bio-engineering 5,6 , and microfluidics 7 . Complex to fabricate optical devices [8][9][10] and systems can similarly benefit from the ability of 3D printing to create low-cost structures of nearly arbitrary shape 11,12 .…”

Rapid Prototyping across the Spectrum: RF to Optical 3D Electromagnetic Structures

“…Several reports have documented the use of additive manufacturing to fabricate 3D EM devices, including gradient index lenses [25,26] at both microwave [27,28] and optical frequencies [26], and radio frequency lenses that attain resolution beyond the diffraction limit [29,30]. These methods may be utilized to construct 3D EM designs [31,32] that incorporate non-planar geometries and material inhomogeneity [33]. The entire process of designing, fabricating and characterizing these devices and structures is discussed in the next sections along with recent examples of applications of such media in practical systems.…”

“…This interest has spurred the exponential growth in development of fabrication techniques with varied capabilities such as different materials (varying structural and mechanical properties) to resolution (providing a range of feature sizes) [24]. In the context of EM devices and media, these techniques can instead be applied to realize different devices that offer electrical and magnetic properties that can be altered from pure dielectrics with a wide range of refractive indices to conductive materials, all of which can be patterned and molded into geometric structures of macro-/micro-/nano-size features depending on the resolution of the fabrication method [31,32,57]. The same advantages of short turnaround time still apply in the research arena.…”

“…Prototyping processes can be classified into two classes: (i) Subtractive manufacturing: used in traditional fabrication and involves removal of material by methods such as drilling on a macroscale and lithography on a micro/nano scale; (ii) Additive manufacturing: newer technology where a 3D object can be made based on a predefined digital model [24,60]. Examples include 3D printing on a macro-scale [16,57] and ink-jet deposition of nanoscale structures [31,56].…”

Scalable Nonmanufacturing of Nanoparticle Films: A Continuous Automated Langmuir-Blodgett Assembly and Deposition Method

“…Even if that is not the case, producing materials in nanoparticle form (especially by solution methods) can be advantageous if synthesis of bulk material is complicated and/or costly. Irrespective of the motivation behind making the nanoparticles, Nanoparticle in the form of thin film has attracted ever-increasing attention due to its practical application and scientific importance in numerous fields such as nanodevices [1], electronics [2], functional coatings [3]. Therefore, a great number of publications have studied the deposition of nanoparticle thin film.…”