Atomically precise surface engineering for producing imagers

摘要

High-quality surface coatings, and techniques combining the atomic precision of molecular beam epitaxy and atomic layer deposition, to fabricate such high-quality surface coatings are provided. The coatings made in accordance with the techniques set forth by the invention are shown to be capable of forming silicon CCD detectors that demonstrate world record detector quantum efficiency (>50%) in the near and far ultraviolet (155 nm-300 nm). The surface engineering approaches used demonstrate the robustness of detector performance that is obtained by achieving atomic level precision at all steps in the coating fabrication process. As proof of concept, the characterization, materials, and exemplary devices produced are presented along with a comparison to other approaches.

主权项

1. An imager comprising:
an imager substrate having at least a first surface at one end thereof, said surface being passivated with a passivation layer comprising at least a delta-doped layer, the delta-doped passivation layer having an atomic monolayer composition profile having an out-of-plane atomic size scale precision of less than 2 nm, and forming a passivated substrate surface such that the delta-dope passivation layer does not interrupt the imager substrate epitaxy; an anti-reflective coating formed on at least a portion of said passivated substrate surface, said anti-reflective coating formed of at least one dielectric material selected to allow imaging across a selected spectral range, and being chemically compatible with the delta-doped layer; wherein the anti-reflective coating is formed of a plurality of layers of the at least one dielectric material, each layer being formed with a thickness of from 0.1 to 3 Angstroms, the anti-reflective coating being disposed on the passivated substrate surface with a density sufficient to ensure that the anti-reflective coating covers the passivated surface continuously on an atomic size scale, such that the anti-reflective coating has a low density of atomic scale defects; wherein where the anti-reflective coating is formed of a material that is chemically reactive with the imager substrate further comprising an optically inactive barrier layer disposed between the imager substrate and the anti-reflective coating; wherein at least the barrier layer and the layers of the anti-reflective coating disposed proximal to the passivated substrate surface conform to the passivated substrate surface such that an interfacial region having an out-of-plane roughness of less than about 3 nm is formed between said passivated substrate surface and the barrier layer and anti-reflective coating; and wherein the imager is formed having an absolute quantum efficiency of at least 50% over at least a portion of the wavelength range of 100 to 300 nm.