Control of dielectric chemical mechanical polishing (CMP) using an interferometry based endpoint sensor

Author

Fang, S.J. ; Barda, A. ; Janecko, T. ; Little, W. ; Outley, D. ; Hempel, G. ; Joshi, S. ; Morrison, B. ; Shinn, G.B. ; Birang, M.

Author_Institution

Texas Instrum. Inc., Dallas, TX, USA

fYear

1998

fDate

1-3 Jun 1998

Firstpage

76

Lastpage

78

Abstract

We report on the application of an optical endpoint sensor to various dielectric CMP processes. First, we demonstrate that this endpoint sensor can be used as an in-situ rate monitor. Since this sensor is based on interferometric measurements, the removal rate determined from the endpoint trace agrees well with that calculated from ex-situ measurements (less than 3% error on average). Secondly, we show that this endpoint technique provides excellent control on both shallow trench isolation (STI) and low level interlayer dielectrics (ILD). Although this technique is difficult for high level ILDs, it is the first CMP endpoint technology in the literature that is able to cover a wide variety of dielectric CMP processes

Keywords

chemical mechanical polishing; dielectric thin films; integrated circuit interconnections; integrated circuit measurement; integrated circuit metallisation; integrated circuit yield; isolation technology; light interferometry; optical sensors; process control; CMP endpoint technology; CMP removal rate; dielectric CMP processes; dielectric chemical mechanical polishing; dielectric chemical mechanical polishing control; endpoint sensor; endpoint technique; ex-situ measurements; in-situ rate monitor; interferometric measurements; interferometry based endpoint sensor; interlayer dielectrics; low level interlayer dielectrics; optical endpoint sensor; shallow trench isolation; Chemical sensors; Detectors; Dielectric measurements; Frequency; Metrology; Monitoring; Optical interferometry; Optical sensors; Process control; Thickness measurement;

fLanguage

English

Publisher

ieee

Conference_Titel

Interconnect Technology Conference, 1998. Proceedings of the IEEE 1998 International

Conference_Location

San Francisco, CA

Print_ISBN

0-7803-4285-2

Type

conf

DOI

10.1109/IITC.1998.704756

Filename

704756