Fluid controller

#The present invention relates to a fluid controller that controls the pressure and/or the flow rate of a raw material gas or the like used in a semiconductor process.

#As indicated in Patent Document 1, as a pressure sensor used in a flow rate measuring mechanism or a mass flow controller of this type, a pressure sensor is known that is configured to receive the pressure of fluid on a pressure sensing surface provided on a diaphragm or the like and to measure the fluid pressure on the basis of a positional change of the pressure sensing surface. For pressure sensors using this method, the larger the area of the pressure sensing surface of the pressure receiving member is, the higher the level of sensitivity is.

#Examples of conventional mass flow controllers include one in which a pressure sensor and a flow rate adjusting valve are attached to a body that has formed therein a flow path through which a control-target fluid flows. In recent years, in particular, to meet the demand to arrange a plurality of mass flow controllers side by side in a compact manner, a mass flow controller 100′ has been developed, as illustrated in FIG. 15, so as to have an oblong body 1′, while a face thereof extending parallel to the longitudinal direction thereof is designated as a component part attachment face 1x′, so that pressure sensors 2′ and a flow rate adjusting valve 4′ are attached to the component part attachment face 1x′ in series along the longitudinal direction. The mass flow controller 100′ is designed to keep the width-direction dimension of the entire mass flow controller compact.

#FIG. 1 is a fluid circuit diagram of a mass flow controller according to an embodiment of the present invention.

#FIG. 2 is an overall perspective view of the mass flow controller without a casing attached thereto according to the embodiment.

#FIG. 3 is a longitudinal cross-sectional view illustrating an internal structure of the mass flow controller according to the embodiment.

#Exemplary embodiments of a fluid controller according to the present invention will be explained below, with reference to the accompanying drawings.

#A fluid controller 100 according to an embodiment may be installed on a gas panel, for example, and may constitute a part of a material supply line for a semiconductor manufacturing apparatus. As shown in the fluid circuit diagram in FIG. 1 and the overall perspective view in FIG. 2, the fluid controller 100 is a mass flow controller including: a body unit 1 having an internal flow path 1a through which fluid serving as a target of flow-rate control flows; a flow rate adjusting valve 4 that is provided in the internal flow path 1a and serves as a fluid controlling valve; a flow rate measuring mechanism 10 that is provided on the downstream side of the flow rate adjusting valve 4 and measures a mass flow rate of the fluid flowing through the internal flow path 1a; and a controlling circuit 6 (not shown in FIG. 2) that controls the flow rate adjusting valve 4 in such a manner that the flow rate measured by the flow rate measuring mechanism 10 becomes equal to a predetermined target flow rate. These functional units will be explained in detail below.

#As shown in FIG. 2, the body unit 1 has an oblong parallelepiped shape. One of the faces of the body unit 1 that extends parallel to the longitudinal direction thereof is designated as a component part attachment face 1x. It is possible to attach component parts such as the flow rate adjusting valve 4 and pressure sensors 2A and 2B only onto the component part attachment face 1x. Further, the face opposite from the component part attachment face 1x is designated as a fixation face by which the body unit 1 is fixed to a panel or the like. Further, the two other faces (hereinafter, “lateral faces”) extending parallel to the longitudinal direction have nothing attached thereto, so that it is possible to arrange a plurality of body units 1 together while the lateral faces thereof are positioned in contact with or positioned close to one another.