SEMI 3D21 - Guide for Describing Glass-Based Material for Use in 3DS-IC Process
With their unique properties and features, non-silicon, dielectric materials have proven to be a valuable alternative to silicon in the semiconductor and 3DS-IC packaging industry. Such non-silicon substrates used as carrier wafers, spacers, interposers, MEMS, RF devices, and lenses. However, until now, little information about the features and characteristics of such base materials was available to the industry.
The non-silicon base material can be further processed to a substrate, which may have through vias, blind vias, and other shaped openings. With vias filled, the substrate may become an interposer. Finally, such substrates may remain in the package in a permanently bonded state or may be removed at the end of the process, such as carrier wafers.
This Guide closes the gap described above and serves as an umbrella document for more specific specifications.
Thereby this Guide enables and describes glass as a base material or substrate of choice for the semiconductor industry.
This Guide is about silicate based materials in their amorphous solid form:
Quartz glass or fusion silicate, which is silicate glass in its purest form.
This Guide describes dimensional, physical, and thermal characteristics of glass as a base material for use in semiconductor applications and 3DS-IC stacks.
The glass base material may permanently remain in the package or device or it may be removed after finishing the process.
The glass base material may be processed further to a substrate with openings, such as but not limited to through vias and blind vias.
The glass substrate is in shape of a wafer (round) or a panel (square or rectangular), but can be of any geometrical shape as specified.
If present, the openings of the glass substrate may be intended to be further processed with metal fillings.
Methods of measurements suitable for determining the characteristics in the Guide are indicated.
Referenced SEMI Standards
SEMI 3D2 — Specification for Glass Carrier Wafers for 3DS-IC Applications
SEMI 3D11 —Terminology for Through Glass Via and Blind Glass Via in Glass Geometrical Metrology
SEMI 3D12 — Guide for Measuring Flatness and Shape of Low Stiffness Substrates
SEMI 3D16 — Specification for Glass Base Material for Semiconductor Packaging
SEMI M59 — Terminology for Silicon Technology