公开(公告)号：US20170287725A1

公开(公告)日：2017-10-05

申请号：US15467939

申请日：2017-03-23

Applicant: Tokyo Electron Limited

Inventor： Antonio L.P. Rotondaro ,  Wallace P. Printz

IPC: H01L21/311 ,  C09K13/06 ,  C09K13/04

CPC classification number: H01L21/31111 ,  C09K13/04 ,  C09K13/06 ,  C09K13/08 ,  H01L21/6708 ,  H01L21/67253 ,  H01L28/00

Abstract: A technique to inhibit the growth of colloidal silica deposits on surfaces treated in phosphoric acid is described. In one embodiment, the disclosed techniques include the use of a colloidal silica growth inhibitor as an additive to a phosphoric acid solution utilized for a silicon nitride etch. In some embodiments, the additive may have chemistry that may contain strong anionic groups. A method and apparatus is provided that monitors the silica concentration and/or the colloidal silica growth inhibitor concentration in the phosphoric acid solution during processing and adjusts the amount of those components as needed. Techniques are provided for a method and apparatus to control the additive concentration to be used as well as the silica concentration in the phosphoric acid solution. The techniques described herein provide a high selectivity etch of silicon nitride towards silicon dioxide without the growth of colloidal silica deposits on the exposed surfaces.

公开(公告)号：US20190237338A1

公开(公告)日：2019-08-01

申请号：US16375984

申请日：2019-04-05

Applicant: Tokyo Electron Limited

Inventor： Antonio L.P. Rotondaro ,  Wallace P. Printz

IPC: H01L21/311 ,  H01L21/67 ,  C09K13/06 ,  C09K13/04

CPC classification number: C09K13/04 ,  C09K13/06 ,  C09K13/08 ,  H01L21/31111 ,  H01L21/67075 ,  H01L21/6708 ,  H01L21/67253 ,  H01L22/10 ,  H01L28/00

Abstract: A technique to inhibit the growth of colloidal silica deposits on surfaces treated in phosphoric acid is described. In one embodiment, the disclosed techniques include the use of a colloidal silica growth inhibitor as an additive to a phosphoric acid solution utilized for a silicon nitride etch. In some embodiments, the additive may have chemistry that may contain strong anionic groups. A method and apparatus is provided that monitors the silica concentration and/or the colloidal silica growth inhibitor concentration in the phosphoric acid solution during processing and adjusts the amount of those components as needed. Techniques are provided for a method and apparatus to control the additive concentration to be used as well as the silica concentration in the phosphoric acid solution. The techniques described herein provide a high selectivity etch of silicon nitride towards silicon dioxide without the growth of colloidal silica deposits on the exposed surfaces.

公开(公告)号：US10325779B2

公开(公告)日：2019-06-18

申请号：US15467939

申请日：2017-03-23

Applicant: Tokyo Electron Limited

Inventor： Antonio L.P. Rotondaro ,  Wallace P. Printz

IPC: H01L21/67 ,  H01L21/311 ,  C09K13/04 ,  C09K13/06

Abstract: A technique to inhibit the growth of colloidal silica deposits on surfaces treated in phosphoric acid is described. In one embodiment, the disclosed techniques include the use of a colloidal silica growth inhibitor as an additive to a phosphoric acid solution utilized for a silicon nitride etch. In some embodiments, the additive may have chemistry that may contain strong anionic groups. A method and apparatus is provided that monitors the silica concentration and/or the colloidal silica growth inhibitor concentration in the phosphoric acid solution during processing and adjusts the amount of those components as needed. Techniques are provided for a method and apparatus to control the additive concentration to be used as well as the silica concentration in the phosphoric acid solution. The techniques described herein provide a high selectivity etch of silicon nitride towards silicon dioxide without the growth of colloidal silica deposits on the exposed surfaces.

公开(公告)号：US20170287726A1

公开(公告)日：2017-10-05

申请号：US15467973

申请日：2017-03-23

Applicant: Tokyo Electron Limited

Inventor： Derek Bassett ,  Wallace P. Printz ,  Antonio L.P. Rotondaro ,  Teruomi Minami ,  Takahiro Furukawa

IPC: H01L21/311 ,  H01L21/67 ,  H01L21/306

CPC classification number: H01L21/31111 ,  H01L21/02052 ,  H01L21/0214 ,  H01L21/02458 ,  H01L21/30608 ,  H01L21/47573 ,  H01L21/6708 ,  H01L21/67253 ,  H01L28/00

Abstract: Techniques are provided to remove the growth of colloidal silica deposits on surfaces of high aspect ratio structures during silicon nitride etch steps. A high selectivity overetch step is used to remove the deposited colloidal silica. The disclosed techniques include the use of phosphoric acid to remove silicon nitride from structures having silicon nitride formed in narrow gap or trench structures having high aspect ratios in which formation of colloidal silica deposits on a surface of the narrow gap or trench through a hydrolysis reaction occurs. A second etch step is used in which the hydrolysis reaction which formed the colloidal silica deposits is reversible, and with the now lower concentration of silica in the nearby phosphoric acid due to the depletion of the silicon nitride, the equilibrium drives the reaction in the reverse direction, dissolving the deposited silica back into solution.