Reduction of Glass Voids in Trenches Filled With Reflowable Glass
Original Publication Date: 1989-Jun-01
Included in the Prior Art Database: 2005-Jan-30
By varying the steam reflow parameters, such as temperature and time, an optimum condition for the void reduction in glass filled trenches can be obtained. Glasses such as borosilicates are easily permeated by steam at temperatures above 700oC. If the sidewall of a deep silicon trench consists of a thermal oxide layer between 250 and 3000 o thickness, a steam reflow of a CVD glass filled trench forms an additional oxide layer, which reduces the size of a glass void formed by the enhanced build up of CVD glasses at the top trench corners during the deposition process.