ACOUSTIC WAVE DEVICE AND MANUFACTURING METHOD OF ACOUSTIC WAVE DEVICE

To rationally prepare a structure that facilitates dissipation of heat of a device chip constituting an acoustic wave device to the outside without complicating the structure and without complicating the manufacturing processes.SOLUTION: An acoustic wave device 1 includes a device chip 3 having a functional surface 3a where a resonator 7 is formed and a back surface 3b facing the functional surface 3a. The functional surface 3a includes a main face part 3e that positions the resonator 7 in a plane surrounded by a predetermined boundary L, and an additional face part 3g positioned outside the main face part 3e. A percentage of a piezoelectric material 3r occupied in a volume of a main part 3f that is a part sandwiched between the main face part 3e and the back surface 3b in the device chip 3 is set to be larger than a percentage of a piezoelectric material r occupied in a volume of an additional part 3h that is a part sandwiched between the additional face part 3g and the back surface 3b in the device chip 3.SELECTED DRAWING: Figure 2 【課題】弾性波デバイスを構成するデバイスチップの熱を外部に放熱しやすくする構造を、その構造の複雑化を招くことなく、かつ、その製造工程の複雑化を招くことなく、合理的に備えさせる。【解決手段】共振器７の形成された機能面３ａと、この機能面３ａに対向する背面３ｂとを持ったデバイスチップ３を備えてなる弾性波デバイス１である。前記機能面３ａは、所定の境界Ｌに囲まれた面内に前記共振器７を位置させる主要面部３ｅと、前記主要面部３ｅ外に位置される付随面部３ｇとからなり、前記デバイスチップ３における前記主要面部３ｅと前記背面３ｂとに挟まれた部分となる主要部３ｆの体積に占める圧電体３ｒの割合が、前記デバイスチップ３における前記付随面部３ｇと前記背面３ｂとに挟まれた部分となる付随部３ｈの体積に占める前記圧電体ｒの割合よりも大きくなるようにしてなる。【選択図】図２