Patent Number: 6,251,807

Title: Method for improving thickness uniformity of deposited ozone-teos silicate glass layers

Abstract: A method for depositing highly conformal silicate glass layers via chemical vapor deposition through the reaction of TEOS and O.sub.3 is disclosed. The entire method, which can be performed in a single cluster tool and even in a single chamber, begins by placing an in-process semiconductor wafer having multiple surface constituents in a plasma-enhanced chemical vapor deposition chamber. A "clean" silicate glass base layer that is substantially free of carbon particle impurities on an upper surface is then formed on the wafer surface in one of two ways. The first employs plasma-enhanced chemical vapor deposition using TEOS and diatomic oxygen gases as precursors to first deposit a "dirty" silicate glass base layer having carbon particle impurities imbedded on an upper surface thereof. The dirty base layer is then transformed to a clean base layer by subjecting it to a plasma treatment, which involves flowing a mixture of a diamagnetic oxygen-containing oxidant, such as ozone or hydrogen peroxide, and diatomic oxygen gas into the chamber and striking an RF plasma at a power density setting of about 0.25 to 3.0 watts/cm.sup.2 for a period from 30-300 seconds. It is hypothesized that the plasma treatment burns off the impurities, which are present in the PECVD-deposited base layer and which may be responsible for certain hydrophilic surface effects which repel TEOS molecules. The plasma treatment also creates a high degree of surface uniformity on the PECVD-deposited glass layer. The second way of forming a clean silicate glass base layer involves flowing hydrogen peroxide vapor and at least one gaseous compound selected from the group consisting of silane and disilane into the deposition chamber. Following the formation of the clean base layer, a subsequent glass layer is deposited over the PECVD-deposited glass layer in the same chamber or cluster tool using chemical vapor deposition and TEOS and ozone as precursor compounds.

Inventors: Iyer; Ravi (Boise, ID)

Assignee: Micron Technology, Inc.

International Classification: C03C 17/02 (20060101); C23C 16/56 (20060101); C23C 16/02 (20060101); C23C 16/40 (20060101); H01L 21/02 (20060101); H01L 21/316 (20060101); H01L 021/31 (); H01L 021/469 ()

Expiration Date: 06/26/2018