Page 10 - Nanosystem Fabrication Facility 2018
P. 10

Wet Etching and CMP Module

                 W       et processing stations play a critical role   Chemical Wet Etching

                         in the semiconductor industry. They are
                 mainly used for substrate cleaning and chemical   Chemical wet etching is the technique of
                 wet etching.                                     removing any barrier material not protected by the
                                                                  hardened photoresist after the photolithography
                 Substrate cleaning is the technique of chemically   process using liquid-phase etchants. Etchants must
                 cleaning silicon wafers prior to thermal oxidation to   be highly purified and filtered. Which etchant to
                 remove from their surfaces particulate matter as well   use depends on the material to be etched. NFF has
                 as any trace of organic, ionic, metallic and bacterial   several specially designed wet processing stations
                 impurities that may contaminate the substrates. NFF   and a wide variety of pre-mixed etchants to
                 houses a high-purity de-ionized water system to   choose from.
                 achieve superior substrate cleaning performance.

                 Equipment                                           Typical Processes Available

                    High-temperature Standard Wafer                     Piranha Cleaning (with H SO  and HF)
                    Cleaning Wet Processing Station
                                                                        RCA1 and RCA2 Cleaning
                    RCA1 / RCA2 Cleaning Wet Processing
                    Station                                             Doped SiO  Etch and Undoped SiO  Etch
                                                                        (with BOE)
                    Silicon Dioxide / Silicon Nitride Etching
                    Wet Processing Station                              Aluminum Etch
                                                                        Pad Etch
                    Chemical Circulation Metal Etching Wet
                    Processing Station                                  Freckle Etch

                    Photoresist Stripping Wet Processing Station        Nitride Etch (with H PO )
                    General Purpose Temperature-controlled              Silicon Etch (with KOH or TMAH)
                    Wet Processing Station

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