System and method for direct-bonding of substrates

Abstract

A MEMS package includes a first substrate having a bonding surface and a second substrate having a polished bonding surface facing the bonding surface of the first substrate. The MEMS package further includes a polished layer of bonding substrate material deposited onto the bonding surface of the first substrate and fusion bonded to the polished bonding surface of the second substrate.

1 . A MEMS package, comprising: 
 a first substrate having a bonding surface;    a second substrate having a polished bonding surface facing the bonding surface of the first substrate; and    a polished layer of bonding substrate material deposited onto the bonding surface of the first substrate and fusion bonded to the polished bonding surface of the second substrate.    
   
   
       2 . A MEMS package according to  claim 1 , wherein the polished bonding surface of the second substrate and the polished layer of bonding substrate material have Angstrom-level flatness.  
   
   
       3 . A MEMS package according to  claim 1 , wherein the first substrate, the second substrate and the bonding substrate material each have a substantially identical refractive index.  
   
   
       4 . A MEMS package according to  claim 1 , wherein the first substrate, the second substrate and the bonding substrate material form a hermetic seal around a MEMS device.  
   
   
       5 . A digital projector, comprising: 
 a MEMS package, wherein the package comprises: 
 a first substrate having a bonding surface;  
 a second substrate having a polished bonding surface facing the bonding surface of the first substrate; and  
 a polished layer of bonding substrate material deposited onto the bonding surface of the first substrate and fusion bonded to the polished bonding surface of the second substrate.  
   
   
   
       6 . A digital projector according to  claim 5 , wherein the polished bonding surface of the second substrate and the polished layer of bonding substrate material have Angstrom-level flatness.  
   
   
       7 . A digital projector according to  claim 5 , wherein the first substrate, the second substrate and the bonding substrate material each have a substantially identical refractive index.  
   
   
       8 . A digital projector according to  claim 5 , wherein the first substrate, the second substrate and the bonding substrate material form a hermetic seal around a MEMS device.  
   
   
       9 . A MEMS package, comprising: 
 a first substrate having a bonding surface;    a second substrate having a polished bonding surface facing the bonding surface of the first substrate; and    means for bonding deposited onto the bonding surface of the first substrate and fusion bonded to the polished bonding surface of the second substrate.    
   
   
       10 . A MEMS package formed by a method comprising the steps of: 
 depositing a layer of bonding substrate material onto a bonding surface of a first substrate;    increasing a bonding site density of at least one of either the layer of bonding substrate material on said first substrate or a bonding surface of a second substrate; and    bonding the bonding surface of the first substrate having the layer of bonding substrate material to the bonding surface of the second substrate.