I copied this from XDA Developers web site but you must be rooted:
What you will need:
Root
Root explorer or similar program
and Be Careful
First:
Open your root explorer or similar app
navigate to system>usr>keylayout
Second:
Make backup of sec_touchscreen.kl
Third
This step has been, found to be not needed. Skip to step 4!
Fourth:
Open sec_touchscreen.kl
find line:
key 158 BACK WAKE_DROPPED
and place a # in front of it like:
# key 158 BACK WAKE_DROPPED
then find line:
key 139 BACK WAKE_DROPPED
and place a # in front of it like:
# key 139 BACK WAKE_DROPPED
Save your changes and close the file
reboot your tablet, and you are finished.
Your capacitive buttons will not respond to your fingers, but retain functionality with the s-pen.
ENJOY!