Patent Application
20150129131
The present disclosure relates to a semiconductor processing apparatus and a pre-clean system.
Various semiconductor manufacturing processes are employed to form the semiconductor devices, including etching, lithography, ion implantation, thin film deposition, and thermal annealing. During the manufacturing of semiconductor devices, unwanted layers (or particles) are often deposited on wafers from known or unknown sources. Such deposition may occur on various layers of a wafer, such as the substrate, photoresist layer, photo mask layer, and/or other layers of the wafer.
A conventional apparatus named Aktiv.™. Preclean (“APC”) chamber is a significant feature of the Endura CuBS (copper barrier/seed) system available from Applied Materials, Inc., and provides a benign and efficient cleaning process for removal of polymeric residues and reaction of copper oxide (“CuO”) for copper low-k interconnect process schemes for 28 nm generation and below nodes. In particular, APC is designed to effectively remove polymeric residues and reduce CuO deposits while preserving the integrity of porous low and ultra-low k inter-level dielectric (“ILD”) films.
The disclosure can be more fully understood by reading the following detailed description of various embodiments, with reference to the accompanying drawings as follows:
The following disclosure provides many different embodiments, or examples, for implementing different features of the invention. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. For example, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed between the first and second features, such that the first and second features may not be in direct contact. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.
The terms used in this specification generally have their ordinary meanings in the art and in the specific context where each term is used. The use of examples in this specification, including examples of any terms discussed herein, is illustrative only, and in no way limits the scope and meaning of the disclosure or of any exemplified term. Likewise, the present disclosure is not limited to various embodiments given in this specification.
It will be understood that, although the terms “first,” “second,” etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of the embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
As used herein, the terms “comprising,” “including,” “having,” “containing,” “involving,” and the like are to be understood to be open-ended, i.e., to mean including but not limited to.
Reference throughout the specification to “one embodiment” or “an embodiment” means that a particular feature, structure, implementation, or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. Thus, uses of the phrases “in one embodiment” or “in an embodiment” in various places throughout the specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, implementation, or characteristics may be combined in any suitable manner in one or more embodiments.
As shown in
In some embodiments, the electromagnetic generator 10 of the semiconductor processing apparatus 1 is a remote plasma power supply, a radio-frequency power supply, or an electric magnet, but the disclosure is not limited in this regard.
In some embodiments, the analog signal module 12 of the semiconductor processing apparatus 1 is a gauge, a controller, or a driver, but the disclosure is not limited in this regard.
As shown in
The electromagnetic shield 14 is the practice of reducing the electromagnetic field in a space by blocking the field with barriers (i.e., the covering plates 140) made of conductive or magnetic materials. Electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as RF shielding.
The electromagnetic shield 14 can reduce the coupling of radio waves, electromagnetic fields, and the full spectrum of electromagnetic radiation. The amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic field.
A variety of materials can be used as electromagnetic shielding to protect the analog signal module 12. Examples include ionized gas in the form of plasma, metal foam with gas-filled pores, or simply sheet metal. In order for holes within the electromagnetic shield 14 to be present, they must be considerably smaller than any wavelength from the electromagnetic field. If the electromagnetic shield 14 contains any openings larger than the wavelength, it cannot effectively prevent the analog signal module 12 from becoming compromised.
Particularly, RF shielding enclosures filter a range of frequencies for specific conditions. Copper is used for RF shielding because it absorbs radio and magnetic waves. Properly designed and constructed copper RF shielding enclosures satisfy most RF shielding needs.
In some embodiments, the predetermined distance is equal to or larger than 20 mm, but the disclosure is not limited in this regard.
In some embodiments, the thickness of each of the covering plates 140 is equal to or larger than 1 mm, but the disclosure is not limited in this regard.
The number of the covering plates 140 in
As shown in
As shown in
As shown in
The mass flow controller 36 is a device used to measure and control the flow of fluids and gases. The mass flow controller 36 is designed and calibrated to control a specific type of fluid or gas at a particular range of flow rates. The mass flow controller 36 can be given a setpoint from 0 to 100% of its full-scale range but is typically operated in the 10 to 90% of full scale where the best accuracy is achieved. The mass flow controller 36 will then control the rate of flow to the given setpoint.
The mass flow controller 36 has an inlet port, an outlet port, a mass flow sensor, and a proportional control valve (not shown). The mass flow controller 36 is fitted with a closed loop control system which is given an input signal by the operator (or an external circuit/computer) that it compares to the value from the mass flow sensor and adjusts the proportional valve accordingly to achieve the required flow. The flow rate is specified as a percentage of its calibrated full-scale flow and is supplied to the mass flow controller 36 as a voltage signal.
The mass flow controller 36 requires the supply gas to be within a specific pressure range. Low pressure will starve the mass flow controller 36 of gas and it may fail to achieve its setpoint. High pressure may cause erratic flow rates.
As shown in
In some embodiments, the shortest distance is equal to or larger than 20 mm, but the disclosure is not limited in this regard.
The number of the covering plates 380 in
In some embodiments, the electromagnetic shield 38 of the pre-clean system 3 further includes a fixing bracket 382. The fixing bracket 382 of the electromagnetic shield 38 is connected to at least one of the covering plates 380 and fixed to a housing of the remote plasma source 34.
As shown in
In some embodiments, the plasma generated by the remote plasma source 34 of the pre-clean system 3 is Hydrogen ion/radical plasma. The pre-clean system 3 further includes an applicator tube 40 and an ion filter 42. The applicator tube 40 of the pre-clean system 3 is communicated between the remote plasma source 34 and the cleaning chamber 30. The ion filter 42 of the pre-clean system 3 is disposed on the applicator tube 40 and located between the remote plasma source 34 and the cleaning chamber 30, and is used to filter ions in the applicator tube 40.
The remote plasma source 34 is defined by the fact that the plasma is only generated and existing in the remote plasma source 34 itself, not in the cleaning chamber 30. No plasma, only radicals (i.e., Hydrogen radicals H*) are reaching the cleaning chamber 30. Hence, reactive hydrogen radicals H* generated by the remote plasma source 34 are capable of entering the cleaning chamber 30 via the applicator tube 40 and the aluminum lid 300.
Therefore, the remote plasma source 34 is ideal for applications that necessarily need to avoid physical effects as ion bombardment and high thermal load. The radicals generated by the remote plasma source 34 are creating only a chemical reaction at the surface of the substrates. That is leading to extremely low thermal load and damage free etching at high rates.
As shown in
Neutral hydrogen radicals H* are unaffected by the electromagnetic field and continue to drift with the gas out of the apertures of the showerhead 48. The hydrogen radicals H* form an excited but neutral gas and do not technically constitute a plasma containing ions and electrons. This description should not be taken as limiting the ion filter to a magnetic filter and other ion filters may be used. Non-limiting examples of suitable ion filters include electrostatic lenses, quadrupole deflectors, Einzel lenses and ion traps.
In some embodiments, the fluid flowing to the remote plasma source 34 controlled by the mass flow controller 36 is a H2O flow. The H2O flow is capable of protecting quartz process kits damage by the Hydrogen radicals H*, and has advantage of particle improvement.
In some embodiments, the cleaning chamber 30 of the pre-clean system 3 is a PVD chamber, but the disclosure is not limited in this regard.
In other words, the pre-clean system 3 in
As shown in
The above illustrations include exemplary steps, but the steps are not necessarily performed in the order shown. Steps may be added, replaced, changed order, and/or eliminated as appropriate, in accordance with the spirit and scope of various embodiments of the present disclosure.
In some embodiments, a semiconductor processing apparatus includes an electromagnetic generator, an analog signal module, and an electromagnetic shield. The electromagnetic generator generates an electromagnetic field. The analog signal module is located adjacent to the electromagnetic generator for generating an analog signal. The electromagnetic shield is used to shield the analog signal module. The electromagnetic shield includes a plurality of covering plates. Each of the covering plates and the analog signal module are apart from a predetermined distance.
Also disclosed is a pre-clean system includes a cleaning chamber, a remote plasma source, a mass flow controller, and an electromagnetic shield. The cleaning chamber includes a lid. The remote plasma source is disposed on the lid for generating a plasma. The mass flow controller is communicated to the remote plasma source for controlling a fluid to flow toward the remote plasma source. The electromagnetic shield is disposed on the lid for shielding the mass flow controller.
A pre-clean system is also disclosed to include a cleaning chamber, a fluid source, a remote plasma source, a mass flow controller, and an electromagnetic shield. The cleaning chamber includes an aluminum lid. The fluid source is used to provide a plurality fluids. The remote plasma source is disposed on the aluminum lid for generating a plasma. The mass flow controller is connected to the fluid source and communicated to the remote plasma source for selectively allowing at least one of the fluids to flow toward the remote plasma source. The electromagnetic shield is disposed on the aluminum lid for shielding the mass flow controller.
According to the foregoing recitations of the embodiments of the disclosure, it can be seen that the semiconductor processing apparatus is capable of preventing the analog signal generated by the analog signal module (e.g., a gauge, a controller, a driver, and etc.) from noise caused by electromagnetic generator 10 by using the electromagnetic shield. Similarly, the pre-clean system is capable of preventing the mass flow controller from electromagnetic interference caused by the remote plasma source by using the electromagnetic shield, so that the mass flow controller can precisely control the processing fluid to flow into the cleaning chamber. Therefore, the high alarm ratio that causes wafer yield lost and increases EE/PE rework loading can be improved. In addition, the electromagnetic shield is low cost for hardware change.
The foregoing outlines features of several embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure.
