Bdtyktl

With my research, it looks like a patent doesn't really make much profit from it due to the high maintenance fee. So I'm thinking is it possible to license my idea to public (for free or way less money) so that anyone can integrate into their product while they can't register as their patent. Something like Creative Common for innovations. Is there such a method?

You are correct that it is quite expensive to patent something in U.S. law.

Under U.S. patent law, once an idea is publicly published, if no one else has a patent application for the same idea that is pending, the idea enters the public domain and no one can obtain a patent of that idea. The publication become "prior art" with respect to any future patent application which cannot be protected by patent law.

Of course, if you publish an invention which you discovered independently, that someone else already has a patent application pending for that will be approved the following week, the fact that you published it after the patent was applied for doesn't prevent the person with the pending patent application from having it approved.

The term "invention" rather than "idea" is what I will use for the remainder of this answer, because there are many ideas which may not be patented, while the lion's share of patentable ideas are appropriately described as "inventions." But, understand that as used in this answer, the term "invention" is being used to refer to the concepts and ideas necessary to make the invention, and not to a particular instance of a product made using those concepts and ideas.

When an invention is in the public domain, anyone can utilize the invention free of charge without a license. People who use the invention are not even required to acknowledge that you invented or discovered it.

An invention is also not eligible to be patented if more than a year has elapsed since the first sale of a product using it. But, in that case, the invention can still be protected as a trade secret until it is voluntarily disclosed in some fashion to someone who is not subject to a non-disclosure agreement. (I say voluntary, because the fact that, for example, an unauthorized corporate spy sees the trade secret doesn't end the status of the invention as a trade secret.)

Some inventions, are effectively publicly disclosed and published the moment that anyone looks at it closely.

The patentable element of other inventions are invisible to an end user, or to observer of an end user.

For example, if the invention involves something in the interior of a device, or the invention involves something not visible to the naked eye (e.g. a process for synthesizing an industrial chemical from other chemicals where the chemical formula of the ingredients and end result can't be determined without a microscope or analytical chemistry tests), merely showing someone a product made using the invention will not put it in the public domain.

It is generally legal to reverse engineer or independently come up with an invention which is merely a trade secret. It is not legal to use a patented invention or process, even if it is not directly copied and is instead reverse engineered or independently discovered, during the lifetime of the patent.

There is no straightforward way to put an invention into the public domain while retaining any right to acknowledgement that you invented it or otherwise exercise control through a licensing agreement without patenting it.