MIM and metal resistor formation at CU beol using only one extra mask
US6730573B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 1, 2002 |
| Grant date | May 4, 2004 |
| Priority date | — |
| Expiry date | Nov 20, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
An improved process for fabricating simultaneously high capacitance, less than 0.13 micron metal-insulator-metal capacitors, metal resistors and metal interconnects, has been developed using single or dual damascene processing. The key advantage is the use of only one additional mask reticle to form both MIM capacitor and resistor, simultaneously. Several current obstacles that exist in BEOL, back end of line, are overcome, namely: (a) the use of two or more photo-masks to make <0.13 um MIM capacitors, (b) undulated copper surfaces, when dielectrics are deposited directly upon it, (c) particles generation concerns during etching, when attempting an etch stop on the bottom MIM plate layers, and finally, (d) dishing during CMP occurs when large copper MIM plates are required, with subsequent capacitance matching problems. The integrated method overcomes the above obstacles and simultaneously forms MIM capacitors, metal resistors and metal interconnects using damascene processing. In addition, the method of forming the MIM capacitors, described herein, can also be used to form anti-fuse devices, in field-programmable gate arrays, FPGA.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.