Abstract: Some embodiments include methods of forming isolation regions in which spin-on material (for example, polysilazane) is converted to a silicon dioxide-containing composition. The conversion may utilize one or more oxygen-containing species (such as ozone) and a temperature of less than or equal to 300° C. In some embodiments, the spin-on material is formed within an opening in a semiconductor material to form a trenched isolation region. Other dielectric materials may be formed within the opening in addition to the silicon dioxide-containing composition formed from the spin-on material. Such other dielectric materials may include silicon dioxide formed by chemical vapor deposition and/or silicon dioxide formed by high-density plasma chemical vapor deposition.

Abstract: A single crystal silicon etching method includes providing a single crystal silicon substrate having at least one trench therein. The substrate is exposed to a buffered fluoride etch solution which undercuts the silicon to provide lateral shelves when patterned in the <100> direction. The resulting structure includes an undercut feature when patterned in the <100> direction.

Abstract: Some embodiments include methods of forming memory arrays. A stack of semiconductor material plates may be patterned to subdivide the plates into pieces. Electrically conductive tiers may be formed along sidewall edges of the pieces. The pieces may then be patterned into an array of wires, with the array having vertical columns and horizontal rows. Individual wires may have first ends joining to the electrically conductive tiers, may have second ends in opposing relation to the first ends, and may have intermediate regions between the first and second ends. Gate material may be formed along the intermediate regions. Memory cell structures may be formed at the second ends of the wires. A plurality of vertically-extending electrical interconnects may be connected to the wires through the memory cell structures, with individual vertically-extending electrical interconnects being along individual columns of the array. Some embodiments include memory arrays incorporated into integrated circuitry.

Abstract: The invention includes methods of forming isolation regions. An opening can be formed to extend into a semiconductor material, and an upper periphery of the opening can be protected with a liner while a lower periphery is unlined. The unlined portion can then be etched to form a widened region of the opening. Subsequently, the opening can be filled with insulative material to form an isolation region. Transistor devices can then be formed on opposing sides of the isolation region, and electrically isolated from one another with the isolation region. The invention also includes semiconductor constructions containing an electrically insulative isolation structure extending into a semiconductor material, with the structure having a bulbous bottom region and a stem region extending upwardly from the bottom region to a surface of the semiconductor material.

Abstract: Some embodiments include methods of forming isolation regions in which spin-on material (for example, polysilazane) is converted to a silicon dioxide-containing composition. The conversion may utilize one or more oxygen-containing species (such as ozone) and a temperature of less than or equal to 300° C. In some embodiments, the spin-on material is formed within an opening in a semiconductor material to form a trenched isolation region. Other dielectric materials may be formed within the opening in addition to the silicon dioxide-containing composition formed from the spin-on material. Such other dielectric materials may include silicon dioxide formed by chemical vapor deposition and/or silicon dioxide formed by high-density plasma chemical vapor deposition.

Abstract: The invention includes semiconductor constructions having trenched isolation regions. The trenches of the trenched isolation regions can include narrow bottom portions and upper wide portions over the bottom portions. Electrically insulative material can fill the upper wide portions while leaving voids within the narrow bottom portions. The trenched isolation regions can be incorporated into a memory array, and/or can be incorporated into an electronic system. The invention also includes methods of forming semiconductor constructions.

Abstract: A wet etching method of removing silicon from a substrate includes depositing a layer comprising silicon in elemental form over a substrate. The layer is exposed to an aqueous liquid etching solution comprising a hydroxide and a fluoride, and having a pH of at least 10, under conditions and for a period of time effective to etch the elemental silicon from the substrate. Wet etching can be employed in methods of forming trench isolation, and in other methods. Other aspects and implementations are contemplated.

Abstract: The invention includes methods in which one or more components of a carboxylic acid having an aqueous acidic dissociation constant of at least 1×10?6 are utilized during the etch of oxide (such as silicon dioxide or doped silicon dioxide). Two or more carboxylic acids can be utilized. Exemplary carboxylic acids include trichloroacetic acid, maleic acid, and citric acid.

Abstract: The invention includes semiconductor constructions having trenched isolation regions. The trenches of the trenched isolation regions can include narrow bottom portions and upper wide portions over the bottom portions. Electrically insulative material can fill the upper wide portions while leaving voids within the narrow bottom portions. The trenched isolation regions can be incorporated into a memory array, and/or can be incorporated into an electronic system. The invention also includes methods of forming semiconductor constructions.

Abstract: The invention includes methods in which one or more components of a carboxylic acid having an aqueous acidic dissociation constant of at least 1×10?6 are utilized during the etch of oxide (such as silicon dioxide or doped silicon dioxide). Two or more carboxylic acids can be utilized. Exemplary carboxylic acids include trichloroacetic acid, maleic acid, and citric acid.

Abstract: A single crystal silicon etching method includes providing a single crystal silicon substrate having at least one trench therein. The single crystal silicon substrate is exposed to an anisotropic etchant that undercuts the single crystal silicon. By controlling the length of the etch, single crystal silicon islands or smooth vertical walls in the single crystal silicon may be created.

Abstract: A single crystal silicon etching method includes providing a single crystal silicon substrate having at least one trench therein. The single crystal silicon substrate is exposed to an anisotropic etchant that undercuts the single crystal silicon. By controlling the length of the etch, single crystal silicon islands or smooth vertical walls in the single crystal silicon may be created.

Abstract: A method of substantially uniformly etching oxides from non-homogeneous substrates is provided. The method utilizes a substantially non-aqueous etchant including an organic solvent and a fluorine-containing compound. The fluorine containing compound may include HF, HF:NH4F, (NH4)HF2, or TMAF:HF and mixtures thereof. The etchant may be applied to chemically non-homogeneous layers such as shallow trench isolation fill oxide layers, or to layers having a non-homogeneous composition or density at different depths within the layers, such as spin-on-glass or spin-on-dielectric films.

Abstract: A single crystal silicon etching method includes providing a single crystal silicon substrate having at least one trench therein. The substrate is exposed to a buffered fluoride etch solution which undercuts the silicon to provide lateral shelves when patterned in the <100> direction. The resulting structure includes an undercut feature when patterned in the <100> direction.

Abstract: Some embodiments include methods of treating semiconductor substrates. The substrates may be exposed to one or more conditions that vary continuously. The conditions may include temperature gradients, concentration gradients of one or more compositions that quench etchant, pH gradients to assist in removing particles, and/or concentration gradients of one or more compositions that assist in removing particles. The continuously varying conditions may be imparted by placing the semiconductor substrates in a bath of flowing rinsing solution, with the bath having at least two feed lines that provide the rinsing solution therein. One of the feed lines may be at a first condition, and the other may be at a second condition that is different from the first condition. The relative amount of rinsing solution provided to the bath by each feed line may be varied to continuously vary the condition within the bath.

Abstract: The invention includes an etchant composition containing isopropyl alcohol and one or more of HF, NH4F and tetramethyl ammonium fluoride (TMAF). The invention encompasses a method of processing a substrate. A substrate is provided which has a first material containing at least one of polysilicon, monocrystalline silicon and amorphous silicon, and a second material. The substrate is exposed to an etch composition which comprises isopropyl alcohol and at least one of HF, NH4F and TMAF. The invention includes a method of processing a semiconductor construction including providing a construction which has a capacitor electrode material and an oxide material along at least a portion of the capacitor electrode material. At least some of the oxide material is removed by isotropic etching utilizing an etchant composition comprising isopropyl alcohol.

Abstract: A single crystal silicon etching method includes providing a single crystal silicon substrate having at least one trench therein. The substrate is exposed to a buffered fluoride etch solution which undercuts the silicon to provide lateral shelves when patterned in the <100> direction. The resulting structure includes an undercut feature when patterned in the <100> direction.

Abstract: Semiconductor devices, structures and systems that utilize a polysilazane-based silicon oxide layer or fill, and methods of making the oxide layer are disclosed. In one embodiment, a polysilazane solution is deposited on a substrate and processed with ozone in a wet oxidation at low temperature to chemically modify the polysilazane material to a silicon oxide layer.

Abstract: Semiconductor devices, structures and systems that utilize a polysilazane-based silicon oxide layer or fill, and methods of making the oxide layer are disclosed. In one embodiment, a polysilazane solution is deposited on a substrate and processed with ozone in a wet oxidation at low temperature to chemically modify the polysilazane material to a silicon oxide layer.

Abstract: Semiconductor devices, structures and systems that utilize a polysilazane-based silicon oxide layer or fill, and methods of making the oxide layer are disclosed. In one embodiment, a polysilazane solution is deposited on a substrate and processed with ozone in a wet oxidation at low temperature to chemically modify the polysilazane material to a silicon oxide layer.