1. Field of the Invention
The present invention relates to a compact camera module (CCM), and more particularly, to a CCM with external filter glass and method for fabricating the same.
2. Description of the Prior Art
With the advent of technology, all kinds of portable electronic instruments and devices have become available. Product components continuously evolve towards lightweight, thin, short, and small devices. How to make an electronic product user-friendly, serve multiple functions, compact in size with ergonomic design that is not only convenient but also fashionable are major topics in the consumer market nowadays. A few examples of significant breakthrough in technological development are mobile phones that come with the function of a digital camera, or a notebook/personal digital assistant (PDA) that also works as a digital camera. All mobile phones on the current market stress compactness. Camera-type mobile phones are particularly popular. Now mobile phones can incorporate 3G functions that allow video communication between caller and recipient via the Internet. Thus the trend of the future for mobile phone is set to be diverse and full functions, and might replace traditional camera modules by utilizing a compact camera module (CCM).
Due to these trends, the development of the CCM in electronic devices tends to minimize the size and manufacturing cost of the CCM. In a prior art CCM fabricating method, a lens unit and an image sensor are fabricated individually, and then assembled by housing the image sensor into the lens unit or bonding the lens unit onto the wafer level image sensor. The lens unit is usually composed of a barrel, lens, spacer, aperture stop and infrared radiation (IR) filter glass. The above-mentioned components implemented in the lens unit need to be fabricated precisely, so that the quality of the lens unit can remain constant. However, the manufacturing cost of the CCM will inevitably be increased.
It is therefore one of the objectives of the present invention to provide a CCM and a method for fabricating the same, that decreases the manufacturing cost typically associated with CCMs.
According to an embodiment of the present invention, an exemplary CCM is disclosed. The exemplary CCM includes an image sensor, a lens unit and a specific filter glass unit. The image sensor is used for sensing an image. The lens unit is used for guiding light beams toward the image sensor. The specific filter glass unit, external to the lens unit and having the image sensor and the lens unit disposed on opposite sides of the specific filter glass unit, is used for filtering out a specific light of the light beams.
According to another embodiment of the present invention, an exemplary method for fabricating a plurality of CCMs is disclosed. The exemplary method includes: providing a plurality of image sensors formed on a wafer, a specific filter glass wafer, and a plurality of lens units; forming a bonded wafer according to the image sensors formed on the wafer, the specific filter glass wafer, and the lens units, wherein the specific filter glass wafer is disposed between the image sensors formed on the wafer and the lens units; and cutting the bonded wafer to generate the CCMs.
According to yet another embodiment of the present invention, an exemplary method for fabricating a CCM is disclosed. The exemplary method includes: providing an image sensor, a specific filter glass unit, and a lens unit; and forming the CCM according to the image sensor, the specific filter glass unit, and the lens unit, wherein the specific filter glass unit is disposed between the image sensor and the lens unit.
These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.
Please refer to
The image sensor 110 and the IR filter glass unit 130 can be connected by a spacer or an adhesive material, and the IR filter glass unit 130 and the lens unit 120 can also be connected by a spacer or an adhesive material. Please refer to
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Step 402: Provide the sensor wafer 310 having a plurality of image sensors 312 formed thereon, the IR filter glass wafer 320, and a plurality of lens units 330.
Step 404: Form the bonded wafer 300 according to the sensor wafer 310, the IR filter glass wafer 320, and the lens units 330, wherein the IR filter glass wafer 320 is disposed between the sensor wafer 310 and the lens units 330.
Step 406: Cut the bonded wafer 300 to generate the CCMs 100. By way of example, the lens unit 120 is one of the lens units 330, the IR filter glass unit 130 is derived from cutting the IR filter glass wafer 320, and the image sensor 110 is one image sensor 312 obtained from cutting the sensor wafer 310.
In step 404, a spacer can be disposed between the wafer 310 and the IR filter glass wafer 320 or disposed between the IR filter glass wafer 320 and the lens units 330, for adjusting focus points of the CCMs 100 by setting a thickness of the spacer. For example, the spacer unit 204 shown in
Please note that the method for fabricating the CCM 100 is not limited in the present invention. With some appropriate modifications made to the disclosed exemplary embodiments without departing from the spirit of the present invention, the CCM 100 of the present invention can also be fabricated one by one, as shown in
In summary, the present invention provides a CCM and a method for fabricating the same. Since the filter glass unit of the CCM is external to the lens unit, the lens unit can be fabricated without executing the cutting and assembling procedures of the filter glass unit, and the lens unit can be bonded to the filter glass wafer according to a yield map of a sensor wafer. Therefore, the manufacturing cost of the CCM is decreased.
Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention.