Back to results
US 6,605,504 B1Granted
Method of manufacturing circuit with buried strap including a liner
AssigneeInfineon Technologies AG
InventorsVenkatachalam C. JaiPrakash, Rajiv Ranade
Life of this patent
Estimating the term…
Abstract
Semiconductor devices having trenches with buried straps therein preventing lateral out-diffusion of dopant are provided along with methods of fabricating such semiconductor devices.
Claims11
A method of fabricating a semiconductor device comprising:
- forming a trench in a semiconductor substrate, the trench having a sidewall;
- forming a collar along the sidewall;
- forming a capacitor, the capacitor including a capacitor fill material having a dopant, the capacitor fill material being formed in a region of the trench;
- recessing the collar to form a divot, wherein a top portion of the collar is recessed below a top surface of the capacitor fill material;
- and
- forming a buried strap including a liner within the divot, whereby the dopant is operable to diffuse through the buried strap in a direction substantially parallel to the sidewall, and the liner acts to reduce diffusion of the dopant in a direction substantially perpendicular to the sidewall.
3 more elements
A method of manufacturing a semiconductor device, the method comprising:
- forming a trench in a semiconductor substrate, the trench having a sidewall defining lower, middle and upper regions;
- forming a node dielectric along the sidewall in the lower region of the trench;
- forming a collar along the sidewall in the middle and upper regions of the trench;
- substantially filling the lower and middle regions with a capacitor fill material, the capacitor fill material comprising polysilicon and a dopant and having a top surface;
- etching a top portion of the collar below the top surface of the capacitor fill material to form a divot;
- depositing a nitride liner within the divot, the nitride liner having a thickness of at least about 22 Å;
- and
- forming a strap fill material within the nitride liner of the divot, wherein the strap fill material and the nitride liner form a buried strap, and the nitride liner permits diffusion of the dopant in direction substantially parallel to the sidewall and acts to reduce diffusion of the dopant in a direction substantially perpendicular to the sidewall.
5 more elements
Dependencies are inferred from the claim text.