Method of depositing an atomic layer on a substrate, which method comprises - supplying a precursor gas from a precursor-gas supply comprised by a deposition head towards the substrate; wherein the precursor-gas supply receives gas from a gas source - having the precursor gas react near, e.g. on, the substrate so as to form an atomic layer; wherein ∘ the deposition head has an output face that at least partly faces the substrate during depositing the atomic layer; and ∘ the output face is provided with the precursor-gas supply and has a substantially rounded shape defining a movement path of the substrate; wherein the method further comprises - moving the precursor-gas supply along the substrate by rotating the deposition head along a rotation trajectory while supplying the precursor gas; thus depositing a stack of atomic layers; and - switching between ∘ supplying the precursor gas from the precursor-gas supply towards the substrate over a first part of the rotation trajectory; and ∘ interrupting supplying the precursor gas from said precursor-gas supply over a second part of the rotation trajectory; wherein the switching between supplying and interrupting the precursor gas supply is provided by a gas switching structure comprising one or more valves or a valve system arranged in a gas flow path between the gas supply and the gas source when the precursor gas supply rotates from the first to the second part of the rotation trajectory. - supplying a precursor gas from a precursor-gas supply comprised by a deposition head towards the substrate; wherein the precursor-gas supply receives gas from a gas source - having the precursor gas react near, e.g. on, the substrate so as to form an atomic layer; wherein ∘ the deposition head has an output face that at least partly faces the substrate during depositing the atomic layer; and ∘ the output face is provided with the precursor-gas supply and has a substantially rounded shape defining a movement path of the substrate; wherein the method further comprises ∘ the deposition head has an output face that at least partly faces the substrate during depositing the atomic layer; and ∘ the output face is provided with the precursor-gas supply and has a substantially rounded shape defining a movement path of the substrate; wherein the method further comprises - moving the precursor-gas supply along the substrate by rotating the deposition head along a rotation trajectory while supplying the precursor gas; thus depositing a stack of atomic layers; and - switching between ∘ supplying the precursor gas from the precursor-gas supply towards the substrate over a first part of the rotation trajectory; and ∘ interrupting supplying the precursor gas from said precursor-gas supply over a second part of the rotation trajectory; wherein the switching between supplying and interrupting the precursor gas supply is provided by a gas switching structure comprising one or more valves or a valve system arranged in a gas flow path between the gas supply and the gas source when the precursor gas supply rotates from the first to the second part of the rotation trajectory. ∘ supplying the precursor gas from the precursor-gas supply towards the substrate over a first part of the rotation trajectory; and ∘ interrupting supplying the precursor gas from said precursor-gas supply over a second part of the rotation trajectory; wherein the switching between supplying and interrupting the precursor gas supply is provided by a gas switching structure comprising one or more valves or a valve system arranged in a gas flow path between the gas supply and the gas source when the precursor gas supply rotates from the first to the second part of the rotation trajectory.