7 148 544

7,148,544 Title:

Semiconductor-on-insulator constructions

The invention includes semiconductor constructions having a thin film stacked resistor in electrical connection with a source/drain region of a transistor device. The resistor includes first and second crystalline layers which may or may not differ from one another. One of the first and second crystalline layers comprises doped silicon/germanium, and the other comprises doped silicon. The transistor device and resistor can be part of an SOI construction formed over a conventional substrate (such as a monocrystalline silicon wafer) or a non-conventional substrate (such as one or more of glass, aluminum oxide, silicon dioxide, metal and plastic). The invention also includes processes of forming semiconductor constructions, and in particular aspects, includes processes of forming resistor constructions.

The invention claimed is:

1. A semiconductor-on-insulator construction, comprising: a substrate; an insulator layer over the substrate; a crystalline layer comprising silicon and germaniumover the insulator layer; a transistor device supported by the crystalline layer, the transistor device comprising a gate and an active region proximate the gate; the active region including a channel region and a pair of source/drain regions; atleast a portion of the active region being within the crystalline layer; an entirety of the active region within the crystalline layer being within a single crystal of the crystalline layer; a resistor in electrical connection with one of thesource/drain regions; the resistor comprising p-doped semiconductive material; wherein the p-doped semiconductive material of the resistor comprises at least two stacked layers of p-doped semiconductive material; and wherein at least one of thestacked layers consists of a p-type doped mixture of Si and Ge.

2. The construction of claim 1 wherein the crystalline layer is a first crystalline layer having a relaxed crystalline lattice; wherein the transistor device comprises a gate dielectric; further comprising a strained crystalline lattice layerbetween the first crystalline layer and the gate dielectric; and wherein the gate dielectric is directly against the strained crystalline lattice layer.

3. The construction of claim 2 wherein the strained crystalline lattice layer includes silicon and germanium.

4. The construction of claim 2 wherein the strained crystalline lattice layer includes silicon.

5. The construction of claim 4 wherein the transistor device is an NFET device.

6. The construction of claim 1 wherein each of the stacked layers is individually monocrystalline.