TECHNOLOGY FOCUS - MECHANICAL ENGINEERING - Preferred Solar Cell: Alternatively, the solar cell comprises: a silicon substrate comprising boron, oxygen and carbon, and a frontside antireflective coating, the frontside antireflective coating comprising at least a silicon carbonitride layer adjacent to the substrate, the layer having a carbon concentration greater than 1 at.%, an oxygen concentration of less than 3 at.%, a hydrogen concentration greater than 10 at.%, and a silicon concentration greater than 37 at.%. In a second alternative case, the solar cell comprises: a silicon substrate comprising boron, oxygen and carbon, and a frontside antireflective coating, the frontside antireflective coating comprising at least a first layer adjacent to the substrate and a second layer located on the first layer opposite the substrate; the first layer comprising silicon carbonitride with a carbon concentration of less than 10 at.%; and the second layer comprising silicon nitride; or a silicon carbonitride with a carbon concentration which is lower than the carbon concentration in the first layer and/or a silicon concentration that is higher than a silicon concentration in the first layer. In a third alternative case, the solar cell comprises: a silicon substrate comprising boron, oxygen and carbon, and a frontside antireflective coating, the frontside antireflective coating comprising at least a first layer adjacent to the substrate and a second layer located on the first layer opposite the substrate; the first layer comprising silicon carbonitride, with a carbon concentration of less than 10 at.% and a hydrogen concentration of less than 14.5 at.%; and the second layer being a hydrogen-containing silicon-based film. In a fourth alternative case, the solar cell comprises: a silicon substrate comprising boron, oxygen and carbon, and a frontside antireflective coating, the frontside antireflective coating comprising at least a first layer adjacent to the substrate and a second layer located on the first layer opposite the substrate; the first layer comprising silicon carbonitride with a carbon concentration of less than 10 at.%; and the second layer comprising silicon carbide, silicon carbonitride, silicon oxycarbide or silicon oxycarbonitride, the carbon concentration in the second layer being greater than the carbon concentration in the first layer. In a fifth alternative case, the solar cell comprises: a silicon substrate comprising boron, oxygen and carbon, and a frontside antireflective coating, the frontside antireflective coating comprising at least a silicon carbonitride layer adjacent to the substrate, the silicon carbonitride layer having a graded carbon concentration with an increasing carbon concentration with increasing distance from the emitter, the first layer having an average carbon concentration of less than 10 at.% within the first 30 nm adjacent to the substrate. In a sixth alternative case, the solar cell comprises: a silicon-based substrate comprising boron, oxygen and carbon, and one or more carbon-containing antireflective and passivation layers, the substrate having two major surfaces and the antireflective and passivation layers being adjacent to one or both of the two major surfaces, and the concentration of carbon in the substrate being greater at the major surface adjacent to the antireflective and passivation layer than it is at a depth within the substrate equidistant from both major surfaces. In a seventh alternative case, the solar cell having a silicon substrate comprises boron, oxygen and carbon, the solar cell manifesting a reduction from original Internal Quantum Efficiency (IQE), at any given wavelength between 400 and 1000 nm, of no greater than 5% following illumination of the solar cell for 72 hours at 1000 W/m2. In an eight alternative case, the solar cell having the silicon substrate comprises boron, oxygen and carbon, the solar cell manifesting a reduction from original IQE, at any given wavelength between 400 and 1000 nm, of no greater than about 2% following illumination of the solar cell for 72 hours at 1000 W/m2. In a ninth alternative case, the solar cell having the silicon substrate comprises boron, oxygen and carbon, the solar cell manifesting a reduction from original IQE, at any given wavelength between 400 and 900 nm, of no greater than about 2% following illumination of the solar cell for 72 hours at 1000 W/m2. In a tenth alternative case, the solar cell having the silicon substrate comprises boron, oxygen and carbon, the solar cell manifesting substantially no reduction from original IQE, at any given wavelength between 400 and 900 nm, following illumination of the solar cell for 72 hours at 1000 W/m2.