Abstract
At present, the research for finding new technical methods of treating materials with plasma, including the development of energy and resource saving technologies for microelectronic manufacturing, is particularly actual.In order to improve the efficiency of microwave plasma chemical ashing of photoresist films from the surface of silicon wafers a two-stage process of treating was developed. The idea of the developed process is that wafers coated with photoresist are pre-heated by microwave energy. This occurs because the microwave energy initially is not spent on the excitation and maintenance of a microwave discharge but it is absorbed by silicon wafers which have a high tangent of dielectric losses. During the next step after the excitation of the microwave discharge the interaction of oxygen plasma with a pre-heated photoresist films proceeds more intensively. The delay of the start of plasma forming process in the vacuum chamber of a plasmatron with respect to the beginning of microwave energy generation by a magnetron leads to the increase of the total rate of photoresist ashing from the surface of silicon wafers approximately 1.7 times. The advantage of this method of microwave plasma chemical processing of semi-conductor wafers is the possibility of intensifying the process without changing the design of microwave discharge module and without increasing the input microwave power supplied into the discharge.
Highlights
At present, in most cases the technology of plasma chemical photoresist ashing from the surface of semiconductor wafers uses high frequency or microwave discharges the main drawback of which is inertia of the process at the beginning of plasma forming process
In order to stimulate the processes of microwave plasma chemical photoresist ashing from the surface of semiconductor wafers we suggest using microwave warming up before the beginning of plasma treatment
The moment of terminating the microwave plasma chemical photoresist ashing from the surface of silicon wafers was controlled with the spectrometer SL 40-2-2048 ISA with 777.96 nm oxygen line intensity
Summary
In most cases the technology of plasma chemical photoresist ashing from the surface of semiconductor wafers uses high frequency or microwave discharges the main drawback of which is inertia of the process at the beginning of plasma forming process. Ashing of photoresist begins with a delay connected with warming up of the reaction-discharge chamber’s construction elements and wafers. The duration of the delay being dependent on the temperature of the reaction-discharge chamber and wafers, and, on the size and volume occupied by semiconductor wafers [8]. The transition of the microelectronic industry to the use of 200 mm and even larger diameter wafers needs reaction discharge chambers of more than 0.005 m3 that significantly affects the duration of photoresist ashing with plasma. The formation of high volume and large area microwave discharges leads to certain construction difficulties as industrial microwave discharge plasma sources are designed for 2.45 GHz frequency characterized by a small electromagnetic wave length (12.2 cm in open space [12]) and a small depth of electromagnetic field’s penetration into plasma
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
