Semiconductor constructions, methods of forming semiconductor constructions, light-conducting conduits, and optical signal propagation assemblies

An optical signal propagation assembly, comprising:

• an optical signal input;
• an optical signal amplifier configured to receive an optical signal from the input and amplify the optical signal, the optical signal amplifier comprising one or more rare earth elements within a matrix material;
• an optical signal receiver;
• and
• an optical signal conduit configured to direct the amplified optical signal to the receiver.

A method of forming a semiconductor construction, comprising:

• providing a semiconductor substrate;
• etching one or more trenches into the substrate;
• lining at least one of the trenches with a first barrier material;
• filling the at least one lined trench with waveguide material;
• doping at least some of the waveguide material with one or more rare earth elements;
• and
• forming a second barrier material over the waveguide material, the second barrier material contacting the first barrier material along sidewalls of the at least one trench.