Patent ID: 8686512

Claim:
An integrated circuit device comprising: a P-channel transistor having a source region, a drain region, and a channel region laterally between the source and drain regions of the P-channel transistor, the source, drain and channel regions of the P-channel transistor collectively defining longitudinal and transverse directions for the P-channel transistor, one of the source and drain regions of the P-channel transistor forming at least part of a first diffusion region; an N-channel transistor having a source region, a drain region, and a channel region laterally between the source and drain regions of the N-channel transistor, the source, drain and channel regions of the N-channel transistor collectively defining longitudinal and transverse directions for the N-channel transistor, one of the source and drain regions of the N-channel transistor forming at least part of a second diffusion region; a first STI region transversely adjacent to the channel region of the P-channel transistor; a second STI region longitudinally adjacent to the first diffusion region; a third STI region transversely adjacent to the channel region of the N-channel transistor; and fourth and fifth STI regions each longitudinally adjacent to the second diffusion region and disposed at longitudinally opposite positions across the second diffusion region, wherein all the STI regions in a first subset of the first, second, third and fourth STI regions contain strained dielectric material with elevations that are at least as high as the channel regions of their respectively adjacent transistors and all the STI regions in a second subset of the first, second, third and fourth STI regions contain strained dielectric material with elevations that are recessed relative to the channel regions of their respectively adjacent transistors, the fifth STI region containing strained dielectric material with the same elevation as the fourth STI region, wherein one of the subsets contains exactly one of the first, second, third and fourth STI regions and the other subset contains the other three of the first, second, third and fourth STI regions, and wherein all of the strained dielectric materials in the first, second, third, fourth and fifth STI regions are strained with the same sign.