  We have fabricated ultrafast dark count-free soft X-ray single-photon
detectors (X-SNSPDs) from TaN with various conduction path widths, and we
compare their properties with corresponding data from a Nb X-SNSPD. The TaN
X-SNSPDs offer an improved detector performance regarding device detection
efficiency, latching and pulse amplitudes. Wide conduction paths allow for a
certain energy-resolving capability in contrast to narrow TaN conduction paths.
However, wide paths also limit the detection efficiency at low temperatures,
which can be explained within a hot-spot model.
