The Nambu-Goto string occupied by a set of scalar fields is studied at finite length and temperature. The string tension for a finite string turns out to be nonvanishing for any value of the temperature reaching a minimum value M̃ ${}_{}{}^2{}_{}{}^{}$(r,τ${)}_{\min }$ for a maximum temperature ${\mathrm{\tau }}_{\mathrm{dec}}^{\max }$. In the limit of an infinitely long string the tension vanishes at the deconfinement temperature ${\mathrm{\tau }}_{\mathrm{dec}}$. Thus it might be that the minimum value of the tension occurring at ${\mathrm{\tau }}_{\mathrm{dec}}^{\max }$ is a signal for a first-order transition (the correlation length being finite) to a deconfined phase with a vanishing tension. The static quark-antiquark potential also shows interesting behavior with the deconfinement radius ${\mathit{r}}_{\mathrm{dec}}$ being independent of the temperature, depending only on the normalized scalar mass parameter μ. When τ approaches ${\mathrm{\tau }}_{\mathrm{dec}}$ the potential becomes flat for large distances, thus losing its ‘‘confining’’ linear character to an unconfining constant. For τ>${\mathrm{\tau }}_{\mathrm{dec}}$ the potential still exists up to a certain maximum separation between quarks where a bifurcating solution appears. This point might represent the breaking of the string and the bifurcating solution, being more energetic, is an excited string.

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