Method of filling large deep trench with high quality oxide for semiconductor devices
First Claim
1. A method of creating a semiconductor device structure with an oxide-filled large deep trench (OFLDT) portion having trench size TCS and trench depth TCD, the method comprises:
- a) providing a bulk semiconductor layer (BSL), having a thickness BSLT>
TCD, and mapping out a large trench top area (LTTA) atop the BSL with its geometry equal to that of OFLDT;
b) partitioning the LTTA into interspersed, complementary interim areas ITA-A and ITA-B each of pre-determined geometry;
c) creating into the top BSL surface, a plurality of interim vertical trenches so as to remove bulk semiconductor materials corresponding to ITA-B till the depth TCD; and
d) selectively forming an interim oxidation prevention layer upon the deep active device trenches; and
e) selectively converting the remaining bulk semiconductor materials corresponding to ITA-A into oxide and, should there be any residual space left between the so-converted ITA-A, filling up the residual space with oxide;
f) removing the interim oxidation prevention layer and forming a liner oxide upon the deep active device trenches.
1 Assignment
0 Petitions
Accused Products
Abstract
A method is disclosed for creating a semiconductor device structure with an oxide-filled large deep trench (OFLDT) portion having trench size TCS and trench depth TCD. 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.
4 Citations
11 Claims
-
1. A method of creating a semiconductor device structure with an oxide-filled large deep trench (OFLDT) portion having trench size TCS and trench depth TCD, the method comprises:
-
a) providing a bulk semiconductor layer (BSL), having a thickness BSLT>
TCD, and mapping out a large trench top area (LTTA) atop the BSL with its geometry equal to that of OFLDT;b) partitioning the LTTA into interspersed, complementary interim areas ITA-A and ITA-B each of pre-determined geometry; c) creating into the top BSL surface, a plurality of interim vertical trenches so as to remove bulk semiconductor materials corresponding to ITA-B till the depth TCD; and d) selectively forming an interim oxidation prevention layer upon the deep active device trenches; and e) selectively converting the remaining bulk semiconductor materials corresponding to ITA-A into oxide and, should there be any residual space left between the so-converted ITA-A, filling up the residual space with oxide; f) removing the interim oxidation prevention layer and forming a liner oxide upon the deep active device trenches. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
Specification