Wafer-to-wafer bonding is the second, after wafer micromachining, most fundamental technology for MEMS. Independent on the specific application, bonding should provide certain level of bonding strength, which can be characterized by either pull or shear force required for delamination of the bonded wafers. It also should provide certain level of hermiticity or permability and some other characteristics such as level of induced stress during bonding, maximum temperature, thermo-mechanical stress due to the TCE difference, etc. The goal of presented novel class of bonding technologies is to decrease bonding area and increase mechanical strength and hermeticity of the bonding. This goal was achieved by a combination of the following: microprofiling the bonding area; making negative slope on the side walls of the trenches; making bridges; matching system of trenches and ridges; system of hooks; system of electrical outputs; spacers; barriers; system of capillaries for external true hermetization, etc. The common principle here is to use the third dimension - thickness of the wafer to achieve new quality, for example, to decrease bonding area on the surface of the wafer but increase total bonding surface and, therefore, increase mechanical strength and hermeticity.
[1]
Q. Tong,et al.
Cool Plasma Activated Surface in Silicon Wafer Direct Bonding Technology
,
1988,
ESSDERC '88: 18th European Solid State Device Research Conference.
[2]
P ? ? ? ? ? ? ? % ? ? ? ?
,
1991
.
[3]
G. Wallis,et al.
Field Assisted Glass‐Metal Sealing
,
1969
.
[4]
G. G. Stokes.
"J."
,
1890,
The New Yale Book of Quotations.
[6]
Timothy J. Drabik,et al.
A new bonding technique for microwave devices
,
1996
.
[7]
Masayoshi Esashi,et al.
Low-temperature silicon-to-silicon anodic bonding with intermediate low melting point glan
,
1990
.