Wide and Deep Oxide Trench in A Semiconductor Substrate with Interspersed Vertical Oxide Ribs
First Claim
1. A method of forming a large deep oxide trench in a semiconductor substrate comprising:
- a) forming, in the semiconductor substrate, a plurality of interim trenches separated by a corresponding number of remaining semiconductor mesas between the interim trenches; and
b) oxidizing the remaining semiconductor mesas until they are substantially converted to oxide.
1 Assignment
0 Petitions
Accused Products
Abstract
A semiconductor device structure with an oxide-filled large deep trench (OFLDT) portion having trench size TCS and trench depth TCD is disclosed. A bulk semiconductor layer (BSL) is provided with a thickness BSLT>TCD. A large trench top area (LTTA) is mapped out atop BSL with its geometry equal to OFLDT. The LTTA is partitioned into interspersed, complementary interim areas ITA-A and ITA-B. Numerous interim vertical trenches of depth TCD are created into the top BSL surface by removing bulk semiconductor materials corresponding to ITA-B. The remaining bulk semiconductor materials corresponding to ITA-A are converted into oxide. If any residual space is still left between the so-converted ITA-A, the residual space is filled up with oxide deposition. Importantly, the geometry of all ITA-A and ITA-B should be configured simple and small enough to facilitate fast and efficient processes of oxide conversion and oxide filling.
-
Citations
9 Claims
-
1. A method of forming a large deep oxide trench in a semiconductor substrate comprising:
-
a) forming, in the semiconductor substrate, a plurality of interim trenches separated by a corresponding number of remaining semiconductor mesas between the interim trenches; and b) oxidizing the remaining semiconductor mesas until they are substantially converted to oxide. - View Dependent Claims (2, 3, 4, 5)
-
- 6. A wide and deep oxide trench in a semiconductor substrate comprising vertical oxide ribs, being made of thermal oxide, interspersed throughout the wide and deep oxide trench.
Specification