Abstract: A micromechanical pressure relief valve arrangement comprises a stack of wafers. An active pressure relief valve is realized within the stack of wafers. A passive pressure relief valve is also realized within the stack of wafers, arranged in parallel to the active pressure relief valve. A check valve, also realized within the stack of wafers, is arranged in series with both the active pressure relief valve and the passive pressure relief valve.

Abstract: A wafer assembly (30) includes a substrate (71), in turn including a wafer (70) or a stack of wafers. The wafer assembly (30) further includes an electrical connection (32) arranged through at least a part of the substrate (71). The electrical connection (32) is made by low-resistance silicon. The electrical connection (32) is positioned in a hole (84) penetrating at least a part of the substrate (71). A surface (78) of the substrate (71) confining the hole (84) is electrically insulating. The electrical connection (32) has at least one protrusion (75), which protrudes transversally to a main extension (83) of the hole (84) and the protrusion (75) protrudes outside a minimum hole diameter (85), as projected in the main extension (83) of the hole (84). Preferably, the protrusion (75) is supported by a support surface (81) of the substrate (71). A manufacturing method is also disclosed.

Abstract: A filter comprises a stack of wafers (28). Each of the wafers has a through hole (6). Edges (7) of the holes together define an internal tube. An interface (32) between adjacent wafers defines filter channels. The filter channels comprises first coarse filter channels (20), second coarse filter channels (22) and fine filter channels (26). The first coarse filter channels are open towards an outer rim (5), extend in a direction from the outer rim and are closed towards the internal tube. The second coarse filter channels are arranged in an opposite manner. The fine filter channels connect the first and second coarse filter channels. The first and second coarse filter channels extend radially (R) and the fine filter channels extend tangentially (T). The first and second coarse filter channels are defined by recesses in a surface of a first wafer and the fine filter channels are defined by recesses, each one encircling the hole, in a surface of a second wafer.

Abstract: A nozzle arrangement for use in a gas thruster is presented. At least one heater micro structure (20) is arranged in a stagnation chamber (12) of the gas thruster. The heater microstructure (20) comprises a core of silicon or a silicon compound coated by a surface metal or metal compound coating. The heater microstructure (20) is manufactured in silicon or a silicon compound and covered by a surface metal coating. The heater microstructure (20) is mounted in the stagnation chamber (12) before or after the coverage of the surface metal or metal compound coating. The coverage is performed by heating the heater microstructure and flowing a gas comprising low quantities of a metal compound. The compound decomposes at the heated heater microstructure (20), forming the surface metal or metal compound coating. The same principles of coating can be used for repairing the heater microstructure (20) in situ.

Abstract: A single use valve (10) comprises a plate (12) having an internal filter structure (28). A sealing substance (20) covers an inlet (14) to the filter structure (28). A heater arrangement (16) is arranged at the plate (12) in the vicinity of the sealing substance (20) for converting electrical current into heat and thereby melting or evaporating the sealing substance (20). The heater arrangement (16) conducts at least a part of the current, and preferably the entire current, along a conduction path not including the sealing substance (20). The melting of the sealing substance (20) thereby becomes independent on the existence of a complete electrical connection through the sealing substance (20). The heater arrangement (16) has therefore preferably its main heat emission in an area surrounding the sealing substance (20). The sealing substance (20) can be of any non-porous material.

Abstract: An isolation valve system includes a main body (32), an actuator body (34) and a sealing membrane (307) arranged at a high pressure portion (36) of the isolation valve system. The sealing membrane mechanically attaches the actuator body to the main body. The sealing membrane further seals the high pressure portion from a low pressure portion (38). A burst plug (315) is arranged against the main body and supports the actuator body. An activation arrangement (50) is arranged for allowing an at least partial displacement of the burst plug, typically causing a phase transition. The sealing membrane is dimensioned to break when the actuator body is moved due to the displacement of the burst plug. The isolation valve system includes preferably a stack (30) of substrates (301-304) being bonded together. The substrates have micromechanical structures, which form at least the actuator body and the sealing membrane.

Abstract: A micromechanical pressure relief valve arrangement (10) comprises a stack of wafers (13). An active pressure relief valve (20) is realized within the stack of wafers (13). A passive pressure relief valve (30) is also realized within said stack of wafers (13), arranged in parallel to the active pressure relief valve (20). A check valve (50), also realized within the stack of wafers (13), is arranged in series with both the active pressure relief valve (20) and the passive pressure relief valve (30).

Abstract: A nozzle arrangement for use in a gas thruster is presented. At least one heater micro structure (20) is arranged in a stagnation chamber (12) of the gas thruster. The heater microstructure (20) comprises a core of silicon or a silicon compound coated by a surface metal or metal compound coating. The heater microstructure (20) is manufactured in silicon or a silicon compound and covered by a surface metal coating. The heater microstructure (20) is mounted in the stagnation chamber (12) before or after the coverage of the surface metal or metal compound coating. The coverage is performed by heating the heater microstructure and flowing a gas comprising low quantities of a metal compound. The compound decomposes at the heated heater microstructure (20), forming the surface metal or metal compound coating. The same principles of coating can be used for repairing the heater microstructure (20) in situ.

Abstract: A wafer assembly (30) includes a substrate (71), in turn including a wafer (70) or a stack of wafers. The wafer assembly (30) further includes an electrical connection (32) arranged through at least a part of the substrate (71). The electrical connection (32) is made by low-resistance silicon. The electrical connection (32) is positioned in a hole (84) penetrating at least a part of the substrate (71). A surface (78) of the substrate (71) confining the hole (84) is electrically insulating. The electrical connection (32) has at least one protrusion (75), which protrudes transversally to a main extension (83) of the hole (84) and the protrusion (75) protrudes outside a minimum hole diameter (85), as projected in the main extension (83) of the hole (84). Preferably, the protrusion (75) is supported by a support surface (81) of the substrate (71). A manufacturing method is also disclosed.

Abstract: A single use valve (10) comprises a plate (12) having an internal filter structure (28). A sealing substance (20) covers an inlet (14) to the filter structure (28). A heater arrangement (16) is arranged at the plate (12) in the vicinity of the sealing substance (20) for converting electrical current into heat and thereby melting or evaporating the sealing substance (20). The heater arrangement (16) conducts at least a part of the current, and preferably the entire current, along a conduction path not including the sealing substance (20). The melting of the sealing substance (20) thereby becomes independent on the existence of a complete electrical connection through the sealing substance (20). The heater arrangement (16) has therefore preferably its main heat emission in an area surrounding the sealing substance (20). The sealing substance (20) can be of any non-porous material.

Abstract: An isolation valve system includes a main body (32), an actuator body (34) and a sealing membrane (307) arranged at a high pressure portion (36) of the isolation valve system. The sealing membrane mechanically attaches the actuator body to the main body. The sealing membrane further seals the high pressure portion from a low pressure portion (38). A burst plug (315) is arranged against the main body and supports the actuator body. An activation arrangement (50) is arranged for allowing an at least partial displacement of the burst plug, typically causing a phase transition. The sealing membrane is dimensioned to break when the actuator body is moved due to the displacement of the burst plug. The isolation valve system includes preferably a stack (30) of substrates (301-304) being bonded together. The substrates have micromechanical structures, which form at least the actuator body and the sealing membrane.