Methods and Compositions for Preparing Ge/Si Semiconductor Substrates

Abstract

The present disclosure describes methods for preparing semiconductor structures, comprising forming a Ge layer on a semiconductor substrate using an admixture of (a) (GeH 3 ) 2 CH 2 and Ge 2 H 6 ; (b) GeH 3 CH 3 and Ge 2 H 6 ; or (c) (GeH 3 ) 2 CH 2 , GeH 3 CH 3 and Ge 2 H 6 , wherein in all cases, Ge 2 H 6 is in excess. The disclosure further provides semiconductor structures formed according to the methods of the invention as well as compositions comprising an admixture of (GeH 3 ) 2 CH 2 and/or GeH 3 CH 3 and Ge 2 H 6 in a ratio of between about 1:5 and 1:30. The methods herein provide, and the semiconductor structures provide, Ge layers formed on semiconductor substrates having threading dislocation density below 10 5 /cm 2 which can be useful in semiconductor devices.

1 - 17 . (canceled) 
     
     
         18 . A semiconductor structure comprising:
 a silicon-based semiconductor substrate, and   a Ge layer formed directly over the silicon-based semiconductor substrate, wherein the Ge layer has a threading dislocation density below 10 5 /cm 2 .   
     
     
         19 . The semiconductor structure of  claim 18 , wherein the substrate comprises Si(100). 
     
     
         20 . The semiconductor structure of  claim 18 , wherein the Ge layer is virtually strain free. 
     
     
         21 . The semiconductor structure of  claim 18 , wherein the Ge layer is virtually atomically flat. 
     
     
         22 . The semiconductor structure of  claim 18 , further comprising a second Si-based layer formed over the Ge layer. 
     
     
         23 . The semiconductor structure of  claim 22 , wherein the second Si-based layer comprises elemental Si. 
     
     
         24 . The semiconductor structure of  claim 22 , further comprising a high-k dielectric layer formed over the second Si-based layer. 
     
     
         25 . The semiconductor structure of  claim 24 , wherein the high-k dielectric layer comprises SiN x , Ta 2 O 5 , Al 2 O 3 , HfSiON, HfO 2 , HfSiO, ZrO 2 , HfZrSiO ZrSiO, La 2 O 3 , LaAlO 3 , PZT, or mixtures thereof. 
     
     
         26 - 41 . (canceled)