A spray nozzle chip (1-1) comprising: a first layer (3) provided with a first layer orifice (3a), and a mechanically flexible nozzle layer (5) provided with a nozzle orifice (5a), wherein the first layer (3) has a valve seat (3b) arranged aligned with the nozzle orifice (5a), wherein the spray nozzle chip (1-1) has a valve functionality obtained by movement of the nozzle layer (5) relative to the valve seat (3b) due to pressure changes, and wherein the nozzle layer (5) is arranged at a distance from the valve seat (3b) when the nozzle layer (5) is in a default non-pressurised state, whereby a gap with a gap length (L) is formed between the nozzle layer (5) and the valve seat (3b), wherein the gap length (L) is smaller than a dimension of a specific bacterial type, to thereby seal against bacterial ingrowth through the nozzle orifice of the specific bacterial type.噴霧噴嘴晶片(1-1)，包含有：第一層(3)，設有第一層孔口(3a)；及機械式撓性噴嘴層(5)，設有噴嘴孔口(5a)，其中第一層(3)具有配置成與噴嘴孔口(5a)對齊的閥座(3b)，其中噴霧噴嘴晶片(1-1)具有由於壓力變化使噴嘴層(5)相對閥座(3b)運動而獲得之閥功能性，及其中當噴嘴層(5)處於預設的非加壓狀態時，噴嘴層(5)配置成離閥座(3b)一段距離，從而在噴嘴層(5)和閥座(3b)之間形成具有間隙長度(L)的間隙，其中間隙長度(L)小於特定細菌類型之尺寸，以藉此密封頂抗細菌經過特定細菌類型的噴嘴孔口向內生長。
