Glass substrate for a semiconductor device and method for making same
AssigneeSemiconductor Energy Laboratory Co., Ltd.
InventorsTakeshi Fukada, Naoya Sakamoto
Life of this patent
Estimating the term…
Abstract
A glass substrate usable for a semiconductor device which shrinks less during a heating process. Specifically, lithium is added to the glass substrate material prior to formation. Further, the glass substrate can be thermal annealed in advance. In accordance with the present invention, it is possible to reduce substrate shrinkage even during TFT processing, by using glass material including more than 4% by weight of lithium, and further by heating the glass substrate at a temperature below the glass strain point temperature.
Claims8
A method of making a glass substrate for a semiconductor device, said method comprising:
- adding more than 4% by weight of lithium to a molten glass material to form a lithium containing glass material;
- forming a glass substrate from said lithium containing glass material;
- thermal annealing said glass substrate in order to shrink said glass substrate prior to preparing said semiconductor device on said glass substrate;
- and
- preparing said semiconductor device on said glass substrate.
A method of making a glass substrate for a semiconductor device, said method comprising:
- adding more than 4% by weight of lithium to a molten glass material to form a lithium containing glass material;
- forming a glass substrate from said lithium containing glass material;
- forming a silicon nitride film having a blocking action to lithium diffusion on the glass substrate;
- forming a silicon oxide film on said silicon nitride film;
- and
- thermal annealing said glass substrate which includes said silicon nitride film and said silicon oxide film at at temperature below a glass strain point of said glass substrate.
A method of making a glass substrate for a semiconductor device, said method comprising:
- adding more than 4% by weight of lithium to a molten glass material to form a lithium containing glass material;
- forming a glass substrate from said lithium containing glass material;
- forming a silicon nitride film, which has a blocking action to lithium diffusion, on said glass substrate;
- forming a silicon oxide film on said silicon nitride film;
- and
- thermal annealing said glass substrate which includes said silicon nitride film and said silicon oxide film.
A method of making a glass substrate for a semiconductor device comprising the step of:
- thermal annealing a glass substrate containing more than 4% by weight of lithium at a temperature less than a glass strain point of said glass substrate;
- and
- preparing said semiconductor device on said glass substrate.
Dependencies are inferred from the claim text.