Phase Equilibria and Vapor Pressures of Pure Phosphorus and of the Indium/Phosphorus System and Their Implications Regarding Crystal Growth of InP

Abstract

The vapor pressure as a function of temperature of several commercial grades of red phosphorus and a specially prepared crystalline sample has been measured. For crystalline red P we obtain a heat of sublimation, δHs=31.9±1 normalkcal/normalmole . The commercial grades yield vapor pressures, which above 450°C are described by the equation In p=−false(10.8±0.4false)×103/T+false(16.5±0.6false) . The sublimation equilibrium of red P can be utilized for controlling phosphorus pressures, p>10 normalatm , with a reproducibility of 10% if commercial P of at least 5N purity is used. Measurements of the pVT relation of phosphorus vapor in the regimes 800°K≤T≤1400°K and 3 normalatm≤p≤35 normalatm reveal deviations up to 10% from ideal gas behavior. Excellent accuracy in describing the behavior of phosphorus vapor is obtained when van der Waals equation is used in conjunction with the critical data of Marckwald and Helmholz and a critical coefficient of 0.375 for calculation of both the co‐volume and the interaction parameter. Consideration of the pressure dependence of the equilibrium constant Kp for the reaction P4=2P2 yielded approximate values for the fugacity constant at 1000° and 1100°C. The pTx relation at the liquidus in the vicinity of stoichiometric InP for indium‐rich and phosphorus‐rich compositions were established by simultaneous vapor pressure and DTA measurements. The melting point of stoichiometric InP is 1335°±1°K and the corresponding equilibrium phosphorus pressure is 27.5±1 normalatm . T−x liquidus data calculated with the assumption of ideal behavior of the liquid are in good agreement with our experimental data. Interpretation of the liquidus pressure data yields values of the standard enthalpies and entropies at 298° K normalΔH°298=22.1 normalkcal/normalmole,normalΔS°298=15.78 normale.normalu. for the reaction normalInP)(normalsfalse)=normalIn)(normals+1/4 P4)(normalg and normalΔH°298=36.0 normalkcal/normalmole,normalΔS°298=25.28 normale.normalu. for the reaction normalInP)(normalsfalse)=normalIn)(normals+1/2 P2)(normalg These results are in excellent accord with the standard enthalpies reported by Panish and Arthur and agree within 3% with literature data on the standard entropies of the reactants. The growth of n‐ and p‐type InP crystals via the gradient freeze technique is discussed and the degree of control of the liquidus concentration is evaluated for various conditions of crystal growth.

Fabrication of ZnSnP2 thin films by phosphidation

“…For processing thin films by phosphidation, we chose a phosphorus source with two phases, Sn and Sn 4 P 3 , because of the difficulties in controlling phosphorus vapor pressure from red phosphorus [11]. The molar ratio of Sn/Sn 4 P 3 was set at about 3, which corresponds to 30 at.% P in the Sn-P binary system, and the total amount was about 2 g. The phosphorus gas was transported to Zn-Sn thin films using Ar carrier gas and the partial pressure of phosphorus was controlled by heating temperature of the phosphorus source.…”

Crystal growth of semiconductor bulk crystals

“…Boron oxide (B2O3) is usually used to overcome this problem [11][12][13]. In the case of gallium arsenide (GaAs), gallium phosphide (GaP) and indium phosphide (InP), arsenic and phosphor have high vapor pressure.…”

“…Boron oxide (B2O3) is usually used to overcome this problem [11][12][13]. The furnace contains a crystal (1), melt (2), a crucible (3,4), pedestals (5,6), thermal shields (7-10) and heaters (11)(12)(13). Therefore, it is easy to remove a grown crystal from the crucible without mechanical breakage of the crystal and crucible.…”

High-Pressure Gradient-Freeze Growth of Single Crystals of Indium Phosphide.

“…Prior to seal off, the ampoule was The electronic properties of several of the crystals were measured. The room-temperature mobilities were in the range from 2500 to 3300 cm 2 /volt-sec, with carrier concentrations in the low-to-mid 101 6 /cm 3 range. All of the material was n-type as grown.…”