Aryl (thio)ether aryl polysiloxane composition and methods for making and using same

1. A method of making an encapsulated semiconductor device, comprising the steps of:

A. providing a curable aryl (thio)ether aryl silicon composition comprising:

at least one silicon-based precursor which is a liquid silicon aryl (thio)ether aryl polysiloxane; and

at least one silicon-based precursor which is a multi-linkable precursor comprising two or more reactive groups capable of reacting with a complementary reactive group of the same or other multi-linkable precursor;

wherein the refractive index of the curable composition is at least 1.50; and

B. curing the curable aryl (thio)ether aryl silicon composition to form the cured aryl (thio)ether aryl polysiloxane composition;

C. providing a semiconductor device comprising semiconductor elements; and

D. forming a coating on at least one surface of at least one of the semiconductor elements by a technique comprising steps selected from:

applying the curable aryl (thio)ether aryl silicon composition to the surface before or during the step (B) of curing;

applying the cured aryl (thio)ether aryl polysiloxane composition to the surface; and

combinations thereof.

2. The method of claim 1 , wherein:

a) the curable aryl (thio)ether aryl silicon composition further comprises a hydrosilation catalyst;

b) the hydrosilation catalyst is a metal or metal compound comprising a Group VIII element selected from platinum, rhodium, palladium, and combinations thereof;

c) at least one multi-linkable precursor is an alkenyl aryl (thio)ether aryl siloxane comprising at least two silicon bonded alkenyl groups;

d) at least one multi-linkable precursor is a hydrido aryl (thio)ether aryl silicon compound comprising at least two silicon bonded hydrogen atoms; and

e) the method comprises the further, optional, step (E) of purifying the cured aryl (thio)ether aryl polysiloxane composition by a technique comprising steps selected from: removing at least a portion of the hydrosilation catalyst; deactivating at least a portion of the hydrosilation catalyst; and combinations thereof.

3. The method of claim 1 , wherein the silicon aryl (thio)ether aryl polysiloxane is an aryl (thio)ether aryl polysiloxane represented by the average compositional Formula I,

(R 1 n SiO (4−n)/2 ) a (O (4−p−r)/2 R 2 p SiZ r SiR 3 q O (4−q−r)/2 ) b   (I),

wherein:

for each (R 1 n SiO (4−n)/2 ) unit:

subscript n equals independently 0, 1, 2, or 3;

for each (O (4−p−r)/2 R 2 p SiZ r SiR 3 q O (4−q−r)/2 ) unit:

subscript p equals 0, 1, 2, or 3;

subscript q equals 0, 1, 2, or 3;

p+q=0 to [8-(2r+1)];

subscript r=1, 2, or 3;

Z is selected from —CHR 4 CHR 5 —X s—, arylene, substituted arylene, and combinations thereof, wherein:

—CHR 4 CHR 5 —X 5 —is the silicon-bridging akylene moiety

X is independently selected from methylene, phenyl, substituted phenyl, oxygen, and combinations thereof;

subscript s=0 or 1; and

R 4 and R 5 are independently selected from hydrogen atom, aryl (thio)ether aryl, and alkyl;

R 1 , R 2 , and R 3 comprise a silicon-bonded organic group selected from alkenyl, hydrogen atom, aryl, alkyl, hydroxy, alkoxy, aryloxy, aryl (thio)ether aryl, other hydrocarbon radical, and combinations thereof;

at least one of R 1 , R 2 , and R 3 comprises a silicon bonded aryl (thio)ether aryl group;

subscripts a and b are selected to conform with the mole fraction of the (R 1 n SiO (4−n)/2 ) unit and the O (4−p−r)/2 R 2 p SiZ r SiR 3 q O (4−q−r)/2 ) unit, respectively;

0≦a≦1; 0≦b≦1; and

a+b=1.

4. The method of claim 3 , wherein the cured aryl (thio)ether aryl polysiloxane composition further comprises a hydrosilation catalyst, wherein:

0<a<1; 0<b <1; and

the hydrosilation catalyst is a metal or metal compound comprising a Group VIII element selected from platinum, rhodium, palladium, and combinations thereof.

5. The method of claim 4 , wherein the hydrosilation catalyst, and any derivatives thereof, is present in a combined amount of at least 0.005 ppm to less than 3.0 ppm, expressed as a Group VIII element equivalent value, based on the total weight of the cured aryl (thio)ether aryl polysiloxane composition.

6. The method of claim 3 , wherein in the cured aryl polysiloxane, at least 70 mole percent to 100 mole percent of R 1 , R 2 , and R 3 combined are aryl (thio)ether aryl and, optionally, a silicon bonded organic group selected from vinyl, hydrogen atom, methyl, phenyl, naphthyl, and combinations thereof.

7. The method of claim 3 , wherein in the cured aryl polysiloxane, at least 70 mole percent to 100 mole percent of R 1 , R 2 , and R 3 combined are phenoxyphenyls and, optionally, phenyl.

8. The method of claim 1 , wherein the curable aryl (thio)ether aryl silicon composition is free of carrier solvent.

9. The method of claim 1 , wherein the refractive index of the composition is at least 1.55.

10. The method of claim 1 , wherein the refractive index of the composition is at least 1.58.