Miniature Smoke Detector chip?

Hi,

I am looking for miniature smoke detector chips.

Most smoke detectors I found (optical, ionization, or both) are in hand-sized enclosures, but I am looking for one much smaller sensor/chip, around 1x1 inch.

Is this technically feasible?
Does this appear very difficult, or costly to develop and produce?
Anyone experienced with smoke detectors?

Thank you.

I'm not going to say that such a small detector doesn't exist - it may. But I do have to wonder:

If such a device existed, and worked well, and was inexpensive to manufacture in mass quantities, then why wouldn't they already be incorporated into existing inexpensive home smoke detectors?

One or more of those three criteria might be why you can't find such a device...