Wafer level packaging, optical detection sensor and method of forming same

Abstract

An optical detection sensor and method of forming same. The optical detection sensor be a proximity detection sensor that includes an optical system and a selectively transmissive structure. Electromagnetic radiation such as laser light can be emitted through a transmissive portion of the selectively transmissive structure. A reflected beam can be detected to determine the presence of an object.

What is claimed is: 
     
         1 . An optical detection apparatus, comprising:
 a device configured to emit electromagnetic radiation;   a structure including a first region of transmissive material to allow a first portion of the electromagnetic radiation to pass through the first region to an exterior of the optical detection apparatus, the structure being configured to reflect a second portion of the electromagnetic radiation; and   a sensor configured to detect the second portion of the electromagnetic radiation.   
     
     
         2 . The optical detection apparatus of  claim 1 , wherein the first region is configured to reflect the second portion of the electromagnetic radiation. 
     
     
         3 . The optical detection apparatus of  claim 2 , wherein the first region has a first surface that receives the electromagnetic radiation and allows the first and second portions of the electromagnetic radiation to pass therethrough, wherein the first region has a second surface that reflects the second portion of the electromagnetic radiation. 
     
     
         4 . The optical detection apparatus of  claim 2 , wherein the first region has an L-shape. 
     
     
         5 . The optical detection apparatus of  claim 1 , wherein the sensor is a first sensor and the structure further includes a second sensor, the second sensor being configured to detect the first portion of the electromagnetic radiation, the first portion of the electromagnetic radiation being reflected from an object at an exterior of the optical detection sensor. 
     
     
         6 . The optical detection apparatus of  claim 5 , wherein the structure further comprises an opaque region separating the device and the second sensor. 
     
     
         7 . The optical detection apparatus of  claim 5 , wherein the structure further comprises a second region of transmissive material to allow the first portion of the electromagnetic radiation reflected from the object to pass through the second region to the second sensor. 
     
     
         8 . The optical detection apparatus of  claim 7 , wherein the first and second regions of transmissive material are embedded in a material that is opaque to the electromagnetic radiation. 
     
     
         9 . The optical detection apparatus of  claim 5 , wherein the first and second sensors are formed in a semiconductor chip. 
     
     
         10 . The optical detection apparatus of  claim 9 , wherein the semiconductor chip is embedded in a material that is opaque to the electromagnetic radiation. 
     
     
         11 . The optical detection apparatus of  claim 1 , wherein the first region of transmissive material is on a first side of the optical detection sensor and the optical detection sensor further comprises at least one conductive material on a second side of the optical detection sensor and electrically connected to the first sensor. 
     
     
         12 . A method of forming at least a selectively transmissive structure, the method comprising:
 forming a first region of transmissive material;   forming a second region of transmissive material;   contacting the first and second regions of transmissive material to an adhesive; and   encapsulating the first and second regions of transmissive material.   
     
     
         13 . The method of  claim 12 , wherein the second region of transmissive material has a shape different from that of the first region of transmissive material, and wherein forming the first region of transmissive material comprises:
 forming trenches in a panel of transmissive material; and   cutting the panel of transmissive material along the trenches.   
     
     
         14 . The method of  claim 12 , wherein encapsulating the first and second regions of transmissive material comprises encapsulating the first and second regions of transmissive material in a polymer material. 
     
     
         15 . The method of  claim 14 , wherein the polymer material comprises an epoxy. 
     
     
         16 . The method of  claim 12 , further comprising removing at least a portion of the adhesive material after encapsulating the first and second regions of transmissive material. 
     
     
         17 . The method of  claim 12 , wherein the first and second regions of transmissive material are encapsulated in an encapsulant, and the method further comprises:
 removing at least a portion of the encapsulant to expose a surface of the first region of transmissive material.   
     
     
         18 . The method of  claim 12 , wherein the first region of transmissive material is formed to have an L-shape. 
     
     
         19 . The method of  claim 12 , further comprising bonding the selectively transmissive structure to an optical system to form an optical detection apparatus. 
     
     
         20 . A method of forming at least an optical system, the method comprising:
 contacting a device for emitting electromagnetic radiation and a sensor chip to an adhesive material, the sensor chip having a plurality of optical sensors; and   encapsulating the device for emitting electromagnetic radiation and the sensor chip.   
     
     
         21 . The method of  claim 20 , further comprising:
 contacting a metal plug to the adhesive material; and   encapsulating the metal plug with the device for emitting electromagnetic radiation and the sensor chip.   
     
     
         22 . The method of  claim 21 , wherein the metal plug, the device and the sensor chip are encapsulated in an encapsulant, and wherein the method further comprises reducing a thickness of the encapsulant to expose a surface of the metal plug. 
     
     
         23 . The method of  claim 20 , further comprising:
 bonding the optical system to a selectively transmissive structure to form an optical detection apparatus.