Process for manufacturing quartz crystal element

Abstract

A process for manufacturing a quartz crystal element consists of the steps of producing plural quartz layers on a surface of a crystalline substrate having a lattice constant differing from that of quartz crystal, in which each of the quartz layers consists of a crystalline phase and an amorphous phase, and percentage of the crystalline phase in the quartz layer farther from the substrate is larger than percentage of the crystalline phase in the quartz layer adjacent to the substrate; and producing an epitaxially grown quartz crystal film on the surface of the quartz layer farther from the substrate by a reaction between silicon alkoxide and oxygen.

1 . A quartz crystal film manufactured by a process comprising the steps of:
 producing at least two quartz layers on a surface of a crystalline substrate having a lattice constant differing from a lattice constant of quartz crystal, in which each of the quartz layers comprises a crystalline phase and an amorphous phase, and percentage of the crystalline phase in the quartz layer farther from the substrate is larger than percentage of the crystalline phase in the quartz layer adjacent to the substrate;   and   producing an epitaxially grown quartz crystal film on the surface of the quartz layer farther from the substrate by a reaction between silicon alkoxide and oxygen.   
     
     
         2 . A quartz crystal element grown with a preferentially orientated AT-cut plane manufactured by a quartz crystal element comprising the steps of:
 producing at least two quartz layers on a surface of a crystalline substrate having a lattice constant differing from a lattice constant of quartz crystal, in which each of the quartz layers comprises a crystalline phase and an amorphous phase, and percentage of the crystalline phase in the quartz layer farther from the substrate is larger than percentage of the crystalline phase in the quartz layer adjacent to the substrate;   and   producing an epitaxially grown quartz crystal film to grow with a preferentially oriented AT-cut plane on the surface of the quartz layer farther from the substrate by a reaction between silicon alkoxide and oxygen.   
     
     
         3 . A quartz crystal element, wherein a quartz crystal film grown with a preferentially oriented AT-cut plane is placed on a surface of a substrate having a lattice constant differing from that of a quartz crystal via at least two quartz layers in which each of the quartz layers comprises a crystalline phase and an amorphous phase, and percentage of the crystalline phase in a quartz layer farther from the substrate is larger than percentage of the crystalline phase in a quartz layer adjacent to the substrate. 
     
     
         4 . The quartz crystal element of  claim 3 , wherein the substrate is a Si substrate, a GaAs substrate, or a sapphire substrate. 
     
     
         5 . The quartz crystal element of  claim 3 , wherein the substrate is a sapphire substrate having a (110) A plane. 
     
     
         6 . A quartz crystal element comprising a quartz crystal film grown with a preferentially oriented AT-cut plane and a quartz layer comprising a crystalline phase and an amorphous phase placed on one side of the quartz crystal film. 
     
     
         7 . A quartz crystal film grown with a preferentially oriented AT-cut plane produced by vapor phase epitaxy.