Elastic wave duplexer having a sealing member that includes a recess

An elastic wave duplexer comprising:

• a substrate;
• a transmission elastic wave filter element that is flip-chip mounted to a principal surface of the substrate;
• a reception elastic wave filter element that is flip-chip mounted to the principal surface of the substrate;
• and
• a sealing member arranged on the principal surface of the substrate to cover at least one of the transmission elastic wave filter element and the reception elastic wave filter element flip-chip mounted to the principal surface of the substrate, which seals off at least one of the transmission elastic wave filter element and the reception elastic wave filter element;
• wherein
• the sealing member includes a recess provided either in a transmission-element-covering region which faces the transmission elastic wave filter element on a side opposite from the substrate with respect to the transmission elastic wave filter element, or in a reception-element-covering region which faces the reception elastic wave filter element on a side opposite from the substrate with respect to the reception elastic wave filter element, such that the transmission-element-covering region and the reception-element-covering region have different thicknesses.